Patent Application
20110034715
The present invention concerns cyclopentadienylphosphazene complexes (CpPN complexes) of the metals of the third and fourth group and of the lanthanoids with the exception of lutetium. In these complexes, the cyclopentadienyl unit (CpPN) is bound as an anionic ligand to the metal atom, and the metal atom is moreover bound to further ligands which do not belong to the CpPN unit. The present invention also relates to methods for producing the CpPN complexes. The complexes according to the present invention are suitable for being used as catalysts for the hydroamination and polymerization of olefins.
The present invention concerns the fields of organometallic chemistry, coordination chemistry, rare-earth chemistry, chemistry of group III and IV of the Periodic Table, catalysis and polymer chemistry.
The addition of amines RR′NH to olefins (hydroamination) takes place only via suitable catalysts. One of the greatest challenges is that of increasing of the catalyst efficiency, particularly in the intermolecular variant. The copolymerization of sterically demanding olefins also requires suitable catalysts.
Metallocene catalysts known to date provide unsatisfactory results in the hydroamination and also the copolymerization of olefins, since the activity, selectivity and breadth of application of the metallocenes is not very high. Such catalysts are described for example in EP 0 416 815 A2, in P J Shapiro, Organometallics 1990, 867-871 and J Okuda, Chem Ber 1990, 1649-871.
Cyclopentadienyl silylamide complexes of the early transition metals—the so-called “constrained geometry catalysts” have evolved to become one of the best tested classes of specially adapted organometallic compounds, since they are used industrially as so-called “single-site catalysts” for olefin polymerization. Single-site catalysts are molecular units of general structure LnMR, in which L is an organic ligand, M represents the metal center of the active catalyst, and R stands for the polymer or the starting group.
Cyclopentadienyl silylamide constrained geometry catalysts of titanium [(CpSiN)TiR2] are widely used in industry, in particular for the copolymerization of sterically demanding olefins. They have the disadvantages mentioned above.
The structure of the CpSiN ligands makes a large number of individual variations of the ligand conceivable. For instance, the nature of the ligand can be varied by varying the substituents on the cyclopentadienyl ring, the bridge unit or on the nitrogen. The ligands on the metal can also be varied. All these variations can of course also be combined.
Further variation possibilities are also apparent taking account of the isolobal relationship between CpSiN and other cyclopentadienyl compounds: It can easily be seen that the bridging silicon atom can be replaced for example by a carbon atom. The amide group can also be replaced by other donor ligands. A large number of these systems have already been synthesized.
Cyclopentadienylphosphazenes are produced by reacting a metallated cyclopentadienyl compound with a chlorodialkyl- or chlorodiarylphosphane, wherein a cyclopentadienylphosphane is obtained. The next synthesis step is a Staudinger reaction. If the desired alkyl-, aryl- or element-organic azide is added to the cyclopentadienylphosphane, the so-called Staudinger adduct is formed, which is stable at lower temperatures.
CpSiN complexes known so far and cyclopentadienyl compounds isolobal thereto are described for example in:
The chelating cyclopentadienylphosphazenes (CpPNs) and cyclopentadienylanylidenes are isolobal to these cyclopentadienyl silylamide complexes. This is described for example in K A Rufanov, Eur J Org Chem 2205, 3805-3807 for a CpPN complex of lutetium. However, one disadvantage here is that lutetium is very rare and expensive and the production of the complex takes place via organometallic starting compounds. Organolanthanoid compounds are often unstable and, due to the resulting obstacles during synthesis, no corresponding CpPN complexes of other lanthanoids are known so far. Many of the previously known lanthanoid complexes comprise THF as the neutral ligand, as shown for example in H Schumann, J Organomet Chem 1993, 462, 155-161 and in W J Evans, Organometallics 1996, 15, 527-531. These complexes are often easily decomposable.
The present invention overcomes the disadvantages of the state of the art by providing for the first time cyclopentadienylphosphazene complexes (CpPN complexes) of the metals of the third and fourth group and of lanthanoids with the exception of lutetium, which [lacuna] as catalysts. The CpPN complexes according to the present invention are suitable for being produced in situ, wherein it is no longer required to make use of the partially unstable alkyl compounds of these metals. Instead, a new in-situ method according to the present invention for the production thereof is presented, in which the easily obtainable and stable metal halides can be used as starting materials.
The complexes according to the present invention are isolobal and isoelectronic to [(CpSiN)TiR2] complexes. They are stable for a long time under an inert atmosphere at room temperature are suitable catalysts for the hydroamination and polymerization of olefins.
The aim of the present invention is therefore to provide cyclopentadienylphosphazene complexes (CpPN complexes) of metals of the third and fourth group and also of lanthanoids with the exception of lutetium, and methods for the production thereof.
This aim is achieved according to the present invention through cyclopentadienylphosphazene complexes (CpPN complexes) of metals of the third and fourth group and of lanthanoids, in which
Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, in which the metal atom
Surprisingly, it has been found that metals of the third and fourth group and also lanthanoids form complexes with cyclopentadienylphosphazene ligands. In these complexes, the cyclopentadienyl unit within the cyclopentadienylphosphazene represents a monoanionic ligand of the metal atom.
Hereinafter, the complexes according to the present invention will be referred to as CpPN complexes.
In a preferred embodiment of the present invention the cyclopentadienylphosphazene unit (CpPN) of the complexes according to the present invention represents a bidentate ligand. In this case, the bonding of the cyclopentadienylphosphazene unit to the metal atom takes place both via the monoanionic cyclopentadienyl unit of the CpPN and also via the nitrogen atom. Cyclopentadienylphosphazene complexes according to the present invention, in which the cyclopentadienylphosphazene unit acts in this way as a bidentate ligand, are referred to as cyclopentadienylphosphazene constrained geometry complexes or—without explicit indication of the hapticity of the ligand—as cyclopentadienylphosphazene constrained geometry complexes. Hereinafter, these complexes are also referred to as CpPN—CGC.
According to these definitions, CpPN-CGCs are always also CpPN complexes.
The term “Constrained Geometry Complex” was originally used in the state of the art for those organometallic complexes in which a pi-ligand (for example a cyclopentadienyl residue) is bound to one of the other ligands on the same metal center in such a way that the bite angle is smaller than a corresponding ligand-metal-ligand angle in comparable unbridged complexes. The term “bite angle” denotes a ligand-metal-ligand angle which is formed when a bidentate or polydentate ligand coordinates to a metal center.
In particular, this term was originally used for ansa-bridged cyclopentadienyl silylamide complexes. The term “Constrained Geometry Complex” (CGC) is meanwhile used for a larger group of complexes and encompasses chelating, donor-functionalized cyclopentadienyl half-sandwich complexes, some of which are isolobal and/or isoelectronic to the ansa-bridged cyclopentadienyl silylamide complexes. This broadened definition of constrained geometry complexes covers for example cyclopentadienylphosphazene complexes and cyclopentadienyiphosphoranylidene complexes, which are both likewise chelating. According to this broadened definition which has now become customary, the constrained geometry complexes also include those cyclopentadienylphosphazene complexes according to the present invention in which both the monoanionic cyclopentadienyl group and the nitrogen atom of the cyclopentadienylphosphazene act as ligands for the metal atom.
The term “isolobal” refers to the similarity of the frontier orbitals of two molecule fragments. Two molecule fragments are “isolobal” if the number, symmetry properties, energy and configuration of their frontier orbitals are similar.
By contrast, two atoms, ions or molecules are “isoelectronic” if they have the same number of electrons, even though they consist of different elements.
Cyclopentadienylphosphazenes in the context of the present invention are structures of the general formula (Ia)
wherein
Optionally, three of the residues R4 and R4′ may be hydrogen, and a substituent R4″ is bound to the fourth carbon atom of the cyclopentadienyl ring according to formula (Ib):
wherein R2 and R3 have the meanings indicated above and R4″ is selected from tert-butyl or —SiMe3.
If R2 and/or R3 are branched or unbranched alkyl groups having 1 to 10 C atoms, these are preferably selected from methyl, ethyl, n-propyl, 2-propyl, n-butyl, 2-butyl, tert-butyl.
In a preferred embodiment
R2 is selected from methyl (Me) and phenyl (Ph) and
R3 is selected from 1-adamantyl, 2,6-diisopropylphenyl, phenyl, tert-butyl and 2,4,6-trimethylphenyl (mesityl).
The monoanionic form of the cyclopentadienylphosphazene (CpPN) is formally formed by abstracting a proton. The monoanionic CpPN ligand of the complexes according to the present invention thus has the general form (Ic)
wherein R2, R3, R4 and R4′ have the meanings indicated above. Structures according to formula (Ib) can be deprotonated in an analogous manner.
Preference is given to those monoanionic cyclopentadienylphosphazenes in which
R2=methyl (Me) or phenyl (Ph),
R3=1-adamantyl (Ad) or 2,6-diisopropylphenyl (Dip) and
R4 and R4′═H or methyl (Me) or
R4, R4′, and the cyclopentadienyl ring together form a 4,4,6,6-tetramethyl-5,6-dihydropentalene-2(4H)-ylidene unit.
The structures of these preferred monoanionic cyclopentadienylphosphazenes are shown below:
In these formula stand
Me for a methyl group, Ph for a phenyl group,
Ad for a 1-adamantyl group, Dip is a 2,6-diisopropylphenyl group and
Cp™ for a 4,4,6,6-tetramethyl-5,6-dihydropentalene-2(4H)-ylidene group.
In uncomplexed cyclopentadienylphosphazenes, the P-amino-cyclopentadienylidenephosphorane form according to formula (Ia) is in tautomeric equilibrium with the corresponding P-cyclopentadienyliminophosphorane structure. This is shown in (II):
According to the invention, metals of the third group are selected from Sc, Y and La and metals of the forth group are selected from Ti, Zr and Hf. Lanthanum (La) is on the one hand a metal of the third group. On the other hand, however, it is also the first representative of the group of the 4f element group named after it, namely the lanthanoids. In the frame of the present invention, La is assigned to the third group, and the “lanthanoids”, which represent the central atoms of the complexes according to the present invention, are understood to be the metals Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb.
In this case, the metal atom is in oxidation stage +III if it is a metal of the third group or a lanthanoid, and is in oxidation stage +IV if it is a metal of the fourth group.
According to the present invention, the metal atom in the CpPN complexes according to the present invention is bound not only to a cyclopentadienylphosphazene unit but also to other ligands. The complex fragment according to the present invention consisting of the metal atom and other ligands is formally a cationic fragment according to formula (III)
wherein M, R1, L, m and p have the following meanings:
and
R1 are anionic ligands which independently of one another are selected from
If R5 is a branched or unbranched alkyl group having 1 to 10 C atoms, this is preferably selected from methyl, ethyl, n-propyl, 2-propyl, n-butyl, 2-butyl, tert-butyl.
Since in the complexes CpPN according to the present invention the cyclopentadienyl unit (within the cyclopentadienylphosphazene) is a monoanionic ligand of the metal atom, then, by combining this monoanionic ligand with the formally cationic fragment according to formula (III), neutral complexes of general formula (IV) are obtained
[(CpPN)MR1m(L)p] (IV),
If R1 represents a group —NR52 according to the above definition, then in the corresponding CpPN complex the cyclopentadienyl unit represents a monoanionic and monodentate ligand of the metal atom, while the nitrogen atom of the cyclopentadienylphosphazene unit does not coordinate to the metal atom. These CpPN complexes are represented by the general formula (V)
wherein m, p, R2, R3, R4, R4′ and R5 and L have the meanings indicated above.
If R1 represents a group according to the definition given above with the exception of —NR52, then in the corresponding CpPN complex the cyclopentadienylphosphazene unit (CpPN) of the complexes according to the present invention represents a bidentate ligand. In this case, the bonding of the cyclopentadienylphosphazene unit to the metal atom takes place both via the monoanionic cyclopentadienyl unit of the CpPN and also via the nitrogen atom. These CpPN-CGC complexes are represented by the general formula (VI)
wherein m, p, R2, R3, R4, R4′ and R5 and L have the meanings indicated above.
In a further embodiment of the present invention, R1 according to the according to the definition above is a halide X selected from fluoride, chloride, bromide, iodide. Formula (VII) shows the anhydrous CpPN complexes of this embodiment:
[(CpPN)MXm(thf)t] (VII)
In this formula, M and m are as defined above, and
In a further embodiment of the present invention, an anionic ligand R1 in the CpPN complex of formula III according to the present invention is replaced by at least one neutral ligand L.
Particular preference is given in this case to those CpPN complexes according to the present invention in which an anionic ligand R1 according to formula III is replaced by a neutral ligand L, resulting in cationic CpPN complexes with an anion X− according to formula (VIII)
[(CpPN)MR6m-1(L)]⊕X⊖ (VIII),
In the frame of the present invention, preference is given to those CpPN complexes according to formulae (IV), (V), (VI), (VII) and (VIII) in which the metal atom is homoleptically coordinated in relation to those anionic ligands which do not represent a cyclopentadienylphosphazene unit.
Very particularly preferred are CpPN complexes of formulae (IV), (V), (VI), (VII) and (VIII) according to the present invention in which the metal atom is homoleptically coordinated by ligands in relation to those anionic ligands which do not represent a cyclopentadienylphosphazene unit, these anionic ligands being selected from the group —CH2Ph, —CH2SiMe3 and NMe2.
The aim of providing the CpPN complexes according to the present invention is achieved according to the invention by an in-situ method comprising the steps
Surprisingly, it has been found that the complexes of formula (IV) according to the present invention can be produced in situ by reacting one equivalent of a metal halide MXq firstly with q equivalents of an alkali metal or alkaline earth metal salt of the ligand R1 (with the exception of the halides and pseudohalides) and subsequently with one equivalent of the protonated cyclopentadienylphosphazene [CpPN]H.
The metal halide MXq is in this case a fluoride, chloride, bromide or iodide of a metal of the third or fourth group or of a lanthanoid, selected from Sc, Y, La, Ti, Zr, Hf, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb. The alkali metal or alkaline earth metal salt of the ligand R1 is the corresponding lithium, sodium, potassium or magnesium salt.
Suitable ethers are for example diethyl ether, dimethyl ether, dimethoxyethane (DME) and tetrahydrofurane (THF).
The in-situ reaction is shown by way of example for a Li salt of the ligand R1 and THF as solvent:
MXq(thf)x+q R1—Li=[MR1q]*q LiX*y(thf)x] (associate) [MR1q]*q LiX*y(thf)x]+[CpPN]H=[(CpPN)M(R1q-1)(thf)y]+q Li—X+R1—H
The Li salt of the ligand R1 is mentioned here by way of example.
R1 and q are as defined above.
THF molecules are bound in the metal halide and in the associate.
x=2 for q=4 and
x=3 for q=3
y, i.e. the number of associated THF molecules, is an integer between 0 and 3 for metals of the third group and lanthanoids and is an integer between 0 and 2 for metals of the fourth group.
Alternatively, the in-situ production of the CpPN complexes of formula (IV) according to the present invention can also take place by first reacting one equivalent of the metal halide MXq with one equivalent of the protonated ligand [CpPN]H and then adding q equivalents of an alkali metal or alkaline earth metal salt of the ligand R1, wherein this in-situ reaction is carried out as described above in an ether as solvent and at temperatures below −70° C.
This alternative in-situ reaction is shown by way of example for a Li salt of the ligand R1 and THF as solvent:
MXq(thf)x+[CpPN]H=[(CpPN—H)MXq(thf)y] [(CpPN—H)MXq(thf)y]+q R1—Li=[(CpPN)M(R1q-1)(thf)y]+q Li—X+R1—H
Here q, x, y and R1 are as defined above.
In a further embodiment, the production of the CpPN complexes of formula (IV) according to the present invention takes place by reacting one equivalent of an isolated compound MR7q with one equivalent of the protonated ligand [CpPN]H in an ether, in an aliphatic tertiary amine, in hexane or in toluene at temperatures below −70° C.
Here R7 is selected from
In this case, the compound MR7q may exist in the form of its etherate or its complex with an aliphatic tertiary amine.
The ether is selected from THF, diethyl ether, dimethyl ether, DME. If instead an aliphatic tertiary amine is used as solvent, then this is selected for example from N,N,N,N-tetramethylethylenediamine, TMEDA or N-methylpyrrolidine.
This production method is formally represented by the following reaction equation:
M(R7)q(ether, amine)x+[CpPN]H=[(CpPN)M(R7)q-1]+R7—H+ether, amine
Here, x, q and R7 have the meanings indicated above.
Complexes of formula VII according to the present invention
[(CpPN)MXm(thf)t] (VII)
are produced by reacting one equivalent of the anhydrous metal halide in an ether at a temperature below −70° C. with an alkali metal or alkaline earth metal salt of the CpPN ligand.
Hereby, the ether is selected from THF, diethyl ether, dimethyl ether, DME (dimethoxyethane). The alkali metal or alkaline earth metal salt is preferably a lithium, sodium, potassium or magnesium salt.
Cationic CpPN complexes of formula VIII according to the present invention
[(CpPN)MR6m-1(L)]⊕X⊖ (VIII)
are produced by reacting the corresponding complex [(CpPN)MR6m] with a cation-generating reagent.
To produce the cationic species, the following cation-generating reagents are used (L is a weakly coordinating solvent molecule), m=2 for a trivalent rare earth metal, m=3 for a quadrivalent group 4 metal:
[(CpPN)M(R6)m]+[MeAlO]z+L=[(CpPN)M(R6)m-1L]++[R6-MeAlO]−
[(CpPN)M(R6)m]+BCF+L=[(CpPN)M(R6)m−1L]++[R6—BCF]−
[(CpPN)M(R6)m]+[H(OR2)2]BARF+L=[(CpPN)M(R6)m-1L]++[BARF]−R6—H
[(CpPN)M(R6)m]+[PhNMe2H][B(C6F5)4]+L=[(CpPN)M(R6)m-1L]++[B(C6F5)4]−+R6—H+PhNMe2
[(CpPN)M(R6)m]+Ph3C[B(C6F5)4]+L=[(CpPN)M(R6)m-1L]++[B(C6F5)4]−+Ph3C—R6
Here, m is as defined above.
During this replacement of an anionic ligand R6 with a neutral ligand L, neither the oxidation stage nor the coordination number of the metal atom change.
The CpPN complexes according to the invention are surprisingly stable. Under an inert atmosphere, they can be stored at RT for at least 6 months.
The neutral CpPN complexes according to the present invention are suitable for being used as catalysts for the intramolecular hydroamination of aminoalkenes. In this case, the catalyst is preferably used in a quantity of 4-6 mol % relative to the aminoalkene.
The cationic CpPN complexes according to the present invention are suitable for being used as catalysts for the polymerization of olefins. For this purpose, the CpPN complex according to the present invention is used in the presence of a scavenger and a co-catalyst. One suitable scavenger is for example triisobutylaluminum (TIBA); suitable co-catalysts are methylaluminoxane (MAO) and tris(pentafluorophenyl)borane (BCF).
15.00 g (84.7 mmol) 2,6-diisopropylphenylamine was added dropwise at −30° C. to 60 mL concentrated hydrochloric acid. A white suspension was formed. To this suspension, a solution of 18.60 g (169.4 mmol) NaBF4 in 30 mL distilled water was added dropwise. Subsequently, a solution of 6.44 g (93.5 mmol) NaNO2 in 20 mL distilled water was added dropwise to this mixture. The suspension turned orange-yellow under the formation of brown vapors. The mixture was stirred for another 35 min at −30° C. and subsequently 70 mL ice water was added and the mixture was warmed to RT. After approximately 10 to 15 min at RT, an orange-colored liquid was formed under a yellow foam. The liquid was drawn off and discarded. Another 70 mL distilled water was added and the orange liquid was drawn from the bottom of the beaker. Using a spatula, the remaining yellow foam was added to a solution of 16.50 g (253.8 mmol) NaN3 that had been cooled to 0° C. The mixture was warmed to RT and stirred for 1.5 h at RT until the incipient gas formation had ended. An orange oily substance was formed in a yellow aqueous solution. The aqueous phase was extracted three times, with 50 mL pentane each. The combined organic phases were dried over MgSO4 and the obtained orange-colored solution was stirred for 12 to 16 hours over silica gel (Merck 60). The silica gel was filtered off and the solvent was removed under vacuum at RT. The yellow oil obtained was filtered over silica gel and eluted with 200 mL pentane. The solvent was again removed under vacuum and the yellow oil was dried under high vacuum.
Yield: 9.24 g (54%)
1H-NMR (300.1 MHz, CDCl3): δ=1.13 (d, 3JHH=6.8 Hz, 12H, Me2CH—), 3.32 (sept, 3JHH=6.8 Hz, 2H, Me2CH—), 7.04-6.93 (m, 3H, C6H3) ppm.
13C-NMR (75.5 MHz, CDCl3): δ=24.0 (s, (CH3)2CH—), 28.5 (s, (CH3)2CH—), 124.2 (s, Cortho), 127.7 (s, Cpara), 137.3 (s, Cmeta), 143.1 (s, Cipso) ppm.
To a suspension of 2.03 g (7.58 mmol) TICp in 25 mL THF, a solution of 1.61 g (7.29 mmol) Ph2PCl was added dropwise at RT. A white suspension in a green-yellowish liquid was formed immediately. The mixture was stirred for 1.5 h and subsequently filtered. The obtained yellow solution was cooled to 0° C. and 1.71 g (8.44 mmol) 2,6-diisopropylphenylazide was added. The solution was stirred at RT for 12 to 16 hours and subsequently heated to 50° C. for 1 h until gas formation was no longer recognizable. The solvent was subsequently removed, the obtained orange solid was suspended in a mixture of hexane/diethyl ether (1:1), filtered, washed with the same solvent mixture, and the bright yellow solid was dried under high vacuum.
Yield: 2.68 g (83%)
CHN: C29H32NP FW 425.55 g/mol
1H-NMR (300.1 MHz, C6D6): δ=0.81 (d, 12H, 3JHH=6.8 Hz, Me2CH—), 3.24 (sept, 2H, 3JHH=6.8 Hz, Me2CH), 4.52 (d, 2JHP=6.2 Hz, 1H, N—H), 6.36 (s, 2H, H-Cp). 6.50 (d, 3,4JHP=5.3 Hz, 2H, H-Cp), 7.01-6.99 (m, 1H, Ar), 7.26-7.18 (m, 2H, Ar), 7.57-7.37 (m, 10H, Ph) ppm.
13C-NMR (75.5 MHz, C6D6): δ=23.0 (Me2CH—), 28.6 (Me2CH—), 83.2 (d, 1 JCP=132.0 Hz, ipso-CCp), 114.5 (d, 2,3JCP=18.9 Hz, CCp), 116.9 (d, 2,3JCP=17.4 Hz, CCp), 123.9 (s, Ar), 126.8 (s, Aripso), 128.2 (d, JCP=12.4 Hz, Ph), 128.3 (Ar), 131.7 (d, JCP=5.9 Hz, Ph), 132.5 (d, JCP=2.9 Hz, Ph), 133.5 (d, JCP=10.9 Hz, Ph), 148.4(d, JCP=2.5 Hz, Ar) ppm.
31P-NMR (121.5 MHz, C6D6): δ=40.7 ppm.
1.07 g (14.7 mmol) LiCp was suspended in a mixture of 60 mL diethyl ether and 60 mL hexane. A solution of 3.60 g (15.5 mmol) Ph2PCl was added dropwise to the suspension, which had been cooled to 0° C. The color of the suspension changed immediately from white to bright yellow. The mixture was warmed to RT and stirred for 12 to 16 hours. The solution was filtered, the solvent was removed and the yellow liquid was dissolved in 10 mL THF. A solution of DipN3 in 10 mL THF was added to the solution of CpPPh2. The color changed immediately from yellow to dark red. In addition, gas formation and warming of the solution could be observed. The solution was stirred for 1 h at RT until gas formation was no longer recognizable. Subsequently, the solution was heated for 1 h to 65° C. A color change to brown could be observed. The solvent was drawn off and replaced by 50 mL hexane. Filtration and subsequent multiple washing with diethyl ether yielded a bright green powder, which was dried under high vacuum.
Yield: 1.464 g (23%)
1H-NMR (300.1 MHz, C6D6): δ=0.79 (d, 12H, 3JHH=7.0 Hz, Me2CH—), 3.35 (sept, 2H, 3JHH=6.8 Hz, Me2CH), 4.64 (br, s, 1H, N—H), 6.82 (d, 3,4JHP=6.4 Hz, 2H, H-Cp), 6.87 (d, 3,4JHP=9.8 Hz, 2H, H-Cp), 7.08-6.98 (m, 8H, Ar, Ph), 7.40-7.34 (m, 6H, Ph) ppm.
31P-NMR (121.5 MHz, C6D6): δ=40.7 ppm.
1.90 g (14.7 mmol) [LiC5Me4H] was suspended in a mixture of 60 mL hexane and 60 mL diethyl ether under stirring for one hour. The suspension was cooled to 0° C. and a solution of 1.50 g (15.5 mmol) Me2PCl in 10 mL diethyl ether was added dropwise over approximately 20 min. The color of the suspension changed immediately from yellow to white. The mixture was warmed to RT and stirred during 12 to 16 hours. After filtration of the mixture, the solvent was removed via vacuum and the obtained yellow oil (2.87 g) was dissolved in 10 mL THF. Subsequently, a solution of 2.90 g (16.3 mmol) AdN3 in 10 mL THF was added dropwise to the C5Me4HPMe2 solution. After a short time, gas formation and a color change from yellow to orange was observed. The solution was stirred for 12 to 16 hours at RT and subsequently heated for 1 h to 50° C. until gas formation was no longer recognizable. The solvent was subsequently removed and the obtained orange-colored solid was suspended in 20 mL hexane. Filtration followed by washing three times with 10 mL hexane each yielded a white powder, which was dried under high vacuum.
Yield: 3.56 g (78%)
CHN: C21H34NP FW 331.48 g/mol
1H-NMR (300.1 MHz, C6D6): δ=1.24 (d, 2JHP=13.0 Hz, 6H, Me2P; 1H, NH-Ad), 1.33-1.31 (br, m, 6H, CH—CH2—CH), 1.40 (br, d, 4JHP=2.7 Hz, 6H, N—C(CH2)3), 1.72 (br, s, 3H, CHAd), 2.48 (s, 6H, C5Me4), 2.50 (s, 6H, C5Me4) ppm.
13C-NMR (75.5 MHz, C6D6): δ=1.2 (s, C5Me4), 4.2 (s, C5Me4), 10.3 (d, 1JCP=67.7 Hz, Me2P), 26.2 (s, CHAd), 35.8 (d, 4JCP=3.3 Hz, CH—CH2—CH), 43.1 (d, 3JCP=6.1 Hz, N—C(CH2)3), 67.6 (s, P—NH—CAd), 70.1 (d, 1JCP=126.5 Hz, ipso-CCp), 107.9 (d, 2,3JCP=16.5 Hz, C(Me)═C(Me)), 109.8 (d, 2,3JCP=18.2 Hz, C(Me)═C(Me)) ppm.
31P-NMR (121.5 MHz, C6D6): δ=35.8 ppm.
213 mg (0.5 mmol) C5H4PPh2NHDip was dissolved in 10 mL THF, the solution was cooled to −78° C. and 0.17 mL (0.5 mmol) of a solution of methyl magnesium chloride in ether (3 M) was slowly added dropwise. The solution was stirred for 30 min each at −78° C., −45° C., 0° C. and at RT. The solution was subsequently heated briefly to boiling, until gas formation was no longer recognizable. The solution was cooled again to −78° C. and added dropwise to a cold solution (−78° C.) of 189 mg (0.5 mmol) [ZrCl4(thf)2] in 20 mL THF. A white precipitate was formed. The mixture was slowly warmed to RT and stirred for 12 to 16 hours at RT. The solvent was removed and the solid was taken up in 20 mL toluene. The orange colored solution was separated from the bright precipitate by filtration. The solvent was removed and the orange-yellow solid was dried under high vacuum. It is soluble in toluene and THF and insoluble in pentane and hexane.
31P-NMR (121.5 MHz, C6D6): 3 signals, main signal at δ=26.1 ppm.
To a solution of 185 mg (0.5 mmol) C5Me4PMe2NHAd in 10 mL THF, 0.17 mL (0.5 mmol) of a solution of methylmagnesium chloride in diethyl ether (3 M) was added dropwise at a temperature of 0° C. This was immediately accompanied by a strong gas formation. The solution was subsequently heated briefly to boiling, until gas formation was no longer recognizable. The solution was subsequently cooled to −78° C. and added dropwise to a solution of 189 mg (0.5 mmol) [ZrCl4(thf)2] in 10 mL THF which had been cooled to −78° C. as well. The solution was warmed to RT during 12 to 16 hours, the solvent was replaced by 15 mL toluene and filtered. After removal of the solvent under vacuum, a pale orange-colored solid was obtained. This solid is very difficult to dissolve in C6D6, insoluble in hexane and pentane and soluble in THF.
31P-NMR (121.5 MHz, C6D6): 16 Signale, Hauptsignal bei δ=33.3 ppm.
888 mg ZrBr4 (2.16 mmol, 1.00 eq) was suspended in 25 mL dichloromethane and 1.00 g C5H4PPh2NDipK (2.16 mmol, 1.00 eq) was added portionwise in solid form at −78° C. It was warmed to RT during 12 to 16 hours, whereby a dark brown suspension was formed. The suspension was centrifuged and the supernatant dark brown solution was decanted and discarded. The solution was removed under high vacuum. The bright brown remainder is insoluble in hexane and Et2O, difficult to dissolve in toluene and benzene, but soluble in dichloromethane, chloroform and THF.
Yield: 820 mg (45%).
CHN: C29H32Br4NPZr MW: 836.39 g/mol
1H-NMR (300.1 MHz, CDCl3): δ=0.91 (br, s, 12H, Me2CH), 3.13 (sept, 4H, 3JHH=6.9 Hz, Me2CH), 3.66 (br, s, 1H, HCp), 6.72 (br, s, 1H, HCp), 6.96 (d, 3JHH=7.8 Hz, 2H, m-Dip), 7.13 (m, 1H, p-Dip), 7.15 (br, s, 1H, HCp), 7.21 (br, s, 1H, HCp), 7.47-7.53 (m, 4H, o-Ph),
7.60-7.68 (m, 6H, m-/p-Ph), 9.79 (d, 2JHP=6.9 Hz, NH) ppm.
13C-NMR (75.5 MHz, CDCl3): δ=23.8 (s, Me2CH), 29.4 (s, Me2CH), 46.2 (d, 2/3JCP=12.6 Hz, CCp), 124.0 (s, m-Dip), 128.4 (s, p-Dip), 129.3 (d, 2JCP=14.7 Hz, o-Ph), 132.6 (d, 2/3JCP=18.6 Hz, CCp), 133.5 (d, 3JCP=10.9 Hz, m-Ph), 134.2 (d, 4JCP=2.7 Hz, p-Ph), 146.9 (d, 2/3JCP=9.1 Hz, CCp), 148.6 (d, 3JCP=3.4 Hz, o-Dip), 156.1 (d, 2/3JCP=14.8 Hz, CCp) ppm.
The signals of the ipso-C atoms cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, CDCl3): δ=27.3 ppm.
El/MS (70 eV)): m/z (%)=425 (17.2) [Ligand+], 382 (21.1) [Ligand+-CHMe2], 177 (35.3) [Dip+], 162 (87.8) [Me2Ph+].
ESI/MS (ACN): m/z (%)=785.4 (29), 614.4 (11), 454.2 (9), 426.2 (100) [ligand+H+].
400 mg ZrBr4 (0.97 mmol, 1.00 eq) was suspended in 10 mL dichloromethane and 360 mg C5Me4PMe2NAdK (0.97 mmol, 1.00 eq) was added at −78° C. It was warmed to RT during 12 to 16 hours, whereby a bright brown suspension was formed. The suspension was centrifuged and the supernatant black solution was decanted. After removal of the solvent under high vacuum, a bright brown solid was obtained. The solid is insoluble in toluene, benzene, hexane and Et2O, but soluble in dichloromethane and chloroform.
31P-NMR (81.0 MHz, CDCl3): δ=main signal at 26.0 ppm (63%), four other signals at: 72.7 (7%), 57.8 (7%), 53.7 (7%), 44.9 (16%) ppm.
311 mg ZrBr4 (0.67 mmol, 1.00 eq) was suspended in 7 mL toluene and 275 mg C5H4PPh2NDipK (0.67 mmol, 1.00 eq) was added at -78° C. It was warmed to RT during 12 to 16 hours, whereby a brown suspension was formed. The brown precipitate was filtered off and washed with 3×5 mL toluene.
The filtrate was reduced to dryness. A bright brown solid remained as remainder.
31P-NMR (81.0 MHz, C6D6): δ=main signal at 28.0 ppm (48%), five other signals at: 31.4 (9%), 28.70 (11%), 28.5 (15%), 14.7 (13%), 13.9 (4%) ppm.
1.00 g C5Me4PMe2NHAd (3.63 mmol, 1.00 eq) was dissolved in 40 mL Dichloromethane and 846 mg ZrCl4 was added in solid form at −78° C. A change in color from orange to beige occurred immediately. The mixture was heated during 12 to 16 hours to RT, whereby a small amount of white precipitate was formed in a burgundy-colored solution. After removal of the solvent under high vacuum, the remainder was dissolved in 30 mL THF and 364 mg KH (9.1 nmol, 2.51 eq) was added. After stirring for 12 to 16 hours at 40° C., the solvent was removed under high vacuum. The pink-colored solid is insoluble in hexane, Et2O and toluene, but soluble in dichloromethane, chloroform and THF.
31P-NMR (81.0 MHz, CDCl3): δ=main signal at 37.4 ppm (68%), three other signals at: 30.3 (18%), 28.9 (7%), 28.1 (7%) ppm.
A solution of 1.38 g Cp™ PPh2NAdK (2.59 mmol, 1.00 eq) in 20 mL THF was added to a solution of 975 mg [ZrCl4(thf)2] (2.59 mmol, 1.00 eq) in 10 mL THF, which had been cooled to −78° C. The black-brown solution was warmed to RT during 12 to 16 hours, whereby a white precipitate was formed. It was filtered over Celite and the filtrate was reduced to dryness. The remainder was suspended in 50 mL hexane, filtered over a fritted funnel, washed twice with 10 mL hexane each and finally dried in high vacuum. The purple solid is insoluble in hexane, difficult to dissolve in benzene and toluene, but soluble in dichloromethane, chloroform and THF.
31P-NMR (81.0 MHz, CDCl3): δ=main signal at 37.8 ppm (59%), another signal at 22.0 (41%)
A solution of 731 mg [Zr(CH2SiMe3)4] (1.66 mmol, 1.00 eq) in 10 mL toluene was cooled to −78° C. and a suspension, also pre-cooled to −78°, of 706 mg C5H4PPh2NHDip (1.66 mmol, 1.00 eq) in 5 mL toluene was added. The bright yellow suspension was warmed to RT during 12 to 16 hours, whereby an orange-colored solution was formed. The solvent was removed in high vacuum and the orange-yellow raw product was recrystallized twice from hexane at −80° C. The yellow solid is difficult to dissolve in pentane and hexane, but soluble in benzene and toluene.
Yield: 474 mg (37%).
CHN: C41H64NPSi3Zr MW: 777.41 g/mol
1H-NMR (300.1 MHz, C6D6): δ=0.20 (s, 27H, Si(CH3)3), 0.89 (s, 6H, Zr—CH2—Si), 1.11 (d, 3JHH=7.0 Hz, 12H, Me2CH), 3.69 (sept, 2H, 3JHH=7.4 Hz, Me2CH), 6.43 (m, 2H, HCp), 6.65 (m, 2H, HCp), 6.99 (m, 6H, m-/p-Ph), 7.03 (m, 2H, m-Dip), 7.13 (m, 1H, p-Dip), 7.42-7.49 (m, 4H, o-Ph) ppm.
13C-NMR (75.5 MHz, C6D6): δ=3.0 (s, Si(CH3)3), 24.2 (Me2CH), 29.2 (Me2CH), 66.6 (s, Zr—CH2—Si), 114.7 (d, 2,3JCP=11.8 Hz, CCp), 115.5 (d, 2,3JCP=7.6 Hz, CCp), 120.8 (d, JCP=2.0 Hz, p-Dip), 123.4 (d, 4JCP=2.1 Hz, m-Dip), 128.7 (s, p-Ph), 131.5 (d, 3JCP=2.3 Hz, m-Ph), 132.2 (d, 2JCP=9.5 Hz, o-Ph) ppm.
The signals of the ipso-C atoms cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, C6D6): δ=−10.9 ppm.
EI/MS (70 eV): m/z (%)=763 (4.2) [(C5H4PPh2NDip)Zr(CH2SiMe3)2(CH2SiMe2)+], 692 (100.0) [(C5H4PPh2NDip)Zr(CH2SiMe3)2+], 514 (77.4), 473 (76.5), 425 (2.9) [ligand+].
IR (Nujol): 1244 [v (P═N)] (s), 1225 (m), 1186 (s), 1049 (m), 744 (s), 704 [v (P—C)] (s), 696 (w), 517 (w), 465 [v Zr—C] (m) cm−1.
Crystal Structure Analysis
F(000) 3312
1.46 g [Zr(CH2SiMe3)4] (3.32 mmol, 1.00 eq) was dissolved in 45 mL toluene and 1.00 g C5H4PMe2NHDip (3.32 mmol, 1.00 eq) was added portionwise in solid form at −78° C. It was warmed to RT during 12 to 16 hours, whereby a reddish brown solution was formed. The solvent was removed in high vacuum and the orange-yellow remainder was recrystallized from hexane at −30° C. The apricot-colored solid is difficult to dissolve in pentane and hexane, but soluble in benzene and toluene.
Yield: 1.66 g (77%).
CHN: C31H60NIPSi3Zr MW: 653.27 g/mol
1H-NMR (300.1 MHz, C6D6): δ=0.36 (s, 27H, Si(CH3)3), 0.91 (s, 6H, Zr—CH2—Si), 1.06 (d, 2JHP=12.3 Hz, PMe2), 1.32 (d, 3JHH=6.8 Hz, 12H, Me2CH), 3.20 (sept, 2H, 3JHH=6.8 Hz, Me2CH), 6.48 (m, 2H, HCp), 6.76 (m, 2H, HCp), 7.13 (m, 2H, m-Dip), 7.24 (m, 1H, p-Dip) ppm.
13C-NMR (75.5 MHz, C6D6): δ=3.7 (s, Si(CH3)3), 15.4 (d, 1JCP=59.6 Hz, PMe2), 25.5 (Me2CH), 28.0 (Me2CH), 61.4 (s, Zr—CH2—Si), 110.0 (d, 2,3JCP=13.1 Hz, CCP), 118.8 (d, 2,3JCP=12.8 Hz, CCp), 123.2 (d, 5JCP=3.4 Hz, p-Dip), 124.4 (d, 4JCP=3.6 Hz, m-Dip), 144.9 (d, 3JCP=6.4 Hz, o-Dip) ppm.
The signal of the ipso-CCp atom cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, C6D6): δ=10.2 ppm.
EI/MS (70 eV): m/z (%)=642 (2.8) [(C5H4PMe2NDip)Zr(CH2SiMe3)2(CH2SiMe2)+], 564 (0.9) [(C5H4PMe2NDip)Zr(CH2SiMe3)2+], 515 (4.1), 301 (3.6) [ligand+], 177 (34.1) [Dip+], 162 (100) [Me2Ph+].
IR (Nujol): 2361 (w), 1240 [v (P═N)] (s), 1225 (m), 1190 (s), 1047 (s), 743 (s), 710 [v (P—C)] (s), 696 (w), 606 (w), 517 (w), 583 (w), 488 (m), 451 [v (Zr—C)] (s) cm−1.
Crystal Structure Analysis
224 mg (0.51 mmol) [Zr(CH2SiMe3)4] was dissolved in 15 mL toluene and cooled to −78° C. To this solution, a suspension of 190 mg (0.51 mmol) C5Me4PMe2NHAd in 15 mL toluene, which had also been cooled to −78°, was added. The mixture was stirred for 6 h at −78° C., during which a clear pale orange solution was formed.
The solution was subsequently warmed to RT. Removal of the solvent and drying in high vacuum resulted in an orange-yellow solid that is soluble in pentane, hexane, toluene and THF.
Yield: 338 mg (97%)
CHN: C33H66NPSi3Zr FW 683.34 g/mol
1H-NMR (300.1 MHz, C6D6): δ=0.35 (s, 27H, —Si—(CH3)3), 0.43 (s, 6H, Zr—CH2—Si), 1.28 (d, 2JPH=12.0 Hz, 6H, Me2P), 1.71-1.59 (br, m, 6H, CH—CH2—CH), 1.89 (br, d, 3JHH=3.6 Hz, 6H, N—C(CH2)3), 1.99 (s, 6H, C5Me4), 2.1 (br, m, 3H, CHAd), 2.06 (s, 6H, C5Me4) ppm.
13C-NMR (75.5 MHz, C6D6): δ=4.4 (s, —Si—Me3), 12.4 (s, C5Me4), 23.0 (d, 1JCP=50.6 Hz, Me2P), 14.8 (s, C5Me4), 30.8 (d, 4JPC=1.6 Hz, CHAd), 36.9 (s, CH—CH2—CH), 48.0 (d, 3JCP=10.4 Hz, N—C(CH2)3), 54.6 (d, 2JCP=5.5 Hz, P═N—CAd), 60.6 (s, Zr—CH2—Si), 121.8 (d, 2,3JCP=12.3 Hz, C(Me)═C(Me)), 126.4 (d, 2,3JCP=12.6 Hz, C(Me)═C(Me)) ppm.
The signal of the ipso-CCp cannot be observed in the 13C-NMR spectrum.
31P-NMR (121.5 MHz, C6D6): δ=29.9 ppm.
EI/MS (70 eV): m/z (%)=332 (1) [ligand+], 170 (25.7), 150 (13.4) [N-Ad+], 135 (35.7) [Ad+], 94 (42.3), 79 (11.5), 77 (16.3) [Me2PN+], 41 (11.0).
IR (Nujol): wave number=3470 (m), 1377 (m), 1303 (m), 1260 [v (P═N)], 1242 (m), 1099 (m), 904 s, 852 (m) cm−1.
1.00 g [Zr(CH2SiMe3)4] (2.27 mmol, 1.00 eq) was dissolved in 50 mL hexane and 626 mg C5Me4PMe2NHAd (2.27 mmol, 1.00 eq) was added portionwise in solid form at −78° C. It was warmed to RT during 12 to 16 hours, whereby a pale orange-colored solution was formed. The solvent was removed in high vacuum and the orange-yellow remainder was recrystallized from hexane at −30° C. The apricot-colored solid is difficult to dissolve in pentane and hexane, but soluble in benzene and toluene.
Yield: 534 mg (34%).
CHN: C33H66NPSi3Zr MW: 683.34 g/mol
1H-NMR (300.1 MHz, C6D6): δ=0.39 (s, 27H, Si(CH3)3), 0.51 (s, 6H, Zr—CH2—Si), 1.29 (d, 2JHP=12.0 Hz, 6H, PMe2), 1.67 (br, m, 6H, CH2Ad), 1.92 (br, m, 6H, N—C(CH2)3), 2.00 (s, 6H, C(Me)═C(Me), 2.09 (br, m, 3H, CHAd; 6H, C(Me)═C(Me) ppm.
13C-NMR (75.5 MHz, C6D6): δ=4.4 (s, Si(CH3)3), 12.5 (s, C(Me)═C(Me)), 14.9 (s, C(Me)═C(Me)), 23.0 (d, 1JCP=50.6 Hz, PMe2), 30.8 (s, CHAd), 36.9 (s, CH2Ad), 48.1 (d, 3JCP=10.3 Hz, N—C(CH2)3), 54.6 (d, 2JCP=4.8 Hz, P═N—CAd), 61.0 (s, Zr—CH2—Si), 121.8 (d, 2,3JCP=12.2 Hz, C(Me)═C(Me)), 126.4 (d, 2,3JCP=12.7 Hz, C(Me)═C(Me)) ppm.
The signal of the ipso-CCp atom cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, C6D6): δ=2.1 ppm.
EI/MS (70 eV): m/z (%)=331 (1.6) [ligand+], 211 (1.8) [Me2PNAd+], 94 (1.6), 73 (100.0).
IR (Nujol): 1260 [v (P═N)] (m), 860 (m), 721 (w) [v (P—C)] (s), 669 (w), 449 [v (Zr—C)] (m) cm−1.
Crystal Structure Analysis
88 mg [Zr(CH2SiMe3)4] (0.20 mmol, 1.00 eq) was dissolved in 5 mL toluene and 100 mg Cp™ PPh2NHAd (2.27 mmol, 1.00 eq) was added portionwise in solid form at −78° C., whereby an orange colored solution was formed. It was warmed to RT during 12 to 16 hours and heated to 60° C. for 7 days. The solvent was removed in high vacuum. The orange-yellow remainder is highly soluble in hexane and toluene, even at −80° C.
31P-NMR (81.0 MHz, toluene): δ=16.6 (43%) [ligand], 13.7 (57%) ppm.
295 mg [Zr(CH2SiMe3)4] (0.67 mmol, 1.00 eq) was dissolved in 10 mL toluene and 350 mg CpH™ PPh2NDip (0.67 mmol, 1.00 eq) was added portionwise in solid form at −78° C., whereby a yellow solution was formed. It was warmed to RT during 12 to 16 hours. The solvent was removed in high vacuum and the yellow remainder was dissolved in 5 mL Et2O and stirred for 4 h at RT.
31P-NMR (81.0 MHz, Et2O): δ=−9.3 (9%), −11.7 (26%), −14.8 (65%) [ligand] ppm.
242 mg [Zr(CH2C6H5)4] (0.53 mmol) was dissolved in 10 mL toluene and cooled to −78° C. To this solution, a suspension of 196 mg (0.53 mmol) C5Me4PMe2NHAd in 10 mL toluene, which had also been cooled to −78°, was added. The mixture was warmed to RT and stirred for 12 to 16 hours. A clear red solution was formed. Removal of the solvent resulted in a red solid that is insoluble in pentane and hexane, but soluble in toluene, benzene and THF.
Yield: 361 mg (97%)
CHN: C42H54NPZr FW 695.08 g/mol
1H-NMR (300.1 MHz, C6D6): δ=1.21 (d, 2JHP=12.87 Hz, 6H, Me2P), 1.35 (br, m, 6H, CH—CH2—CH), 1.65 (s, CH2—Zr), 2.04 (d, 6H, 3JHH=1.36 Hz, N—C(CH2)3), 2.36 (s, 6H, C5Me4), 2.41 (d, 4,5JHP=7.75 Hz, 6H, C5Me4; 3H, CHAd), 7.20-6.80 (m, 15 H, Ph) ppm.
13C-NMR (75.5 MHz, C6D6): δ=12.1 (d, 3,4JCP=3.0 Hz, C5Me4), 14.9 (s, C5Me4), 19.4 (d, 1JCP=69.8 Hz, Me2P), 21.4 (s, Zr—CH2—Ph), 29.9 (s, CHAd), 36.1 (s, CH—CH2—CH), 44.8 (d, 3JCP=4.1 Hz, N—C(CH2)3), 52.5 (d, 2JCP=4.4 Hz, P—N—CAd), 117.7 (d, 2,3JCP=16.6 Hz, C(Me)═C(Me)), 120.7 (d, 2,3JCP=19.6 Hz, C(Me)═C(Me)), 125.6 (Bzpara), 128.5 (Bzmeta), 129.3 (Bzortho), 137.8 (Bzipso) ppm. The signal of the ipso-CCp cannot be observed in the 13C-NMR spectrum.
31P-NMR (121.5 MHz, C6D6): δ=29.9 ppm.
EI/MS (70 eV): m/z (%)=331 (25.2) [ligand+], 211 (100) [Me2PNAd+], 196 (57) [MePNAd+], 170 (10), 154 (37), 150 (12) [NAd+], 135 (73) [Ad+], 105 (21), 94 (72), 91 (22) [Bz+], 79 (36), 77 (31) [Ph+], 61 (18), 55 (11), 41 (35).
IR (Nujol): wave number=3470 (w), 2726 [v (C—CH3)] (m), 2281 (m), 1377 [v (C—C)] (m), 1303 [v (P═N)] (s), 1203 (m), 1154 (s), 1096 (m), 1035 (m), 723 [v (P—C)] (s) cm−1.
UV/VIS (THF): λmax=279 nm.
A suspension of 500 mg [Zr(CH2C6H5)4] (1.09 mmol, 1.00 eq) in 20 mL toluene was cooled to −78° C. and a suspension, also pre-cooled to −78° C., of 464 mg C5H4PPh2NHDip (1.09 mmol, 1.00 eq) in 5 mL toluene was added dropwise. It was was warmed to RT and stirred for 12 to 16 hours, whereby a lemon-yellow suspension and a white precipitate were formed. It was filtered over Celite and the white remainder was washed three times with 5 mL toluene each and the filtrate was reduced to dryness. The yellow-brown remainder is insoluble in hexane, but soluble in benzene, toluene and Et2O.
Yield: 232 mg (27%).
CHN: C50H52NPZr MW: 789.15 g/mol
1H-NMR (300.1 MHz, d8-THF): δ=0.81 (br, s, 12H, Me2CH), 2.52 (br, s, Zr—CH2Ph), 3.37 (m, 2H, Me2CH), 6.10 (m, 2H, HCp), 6.57 (m, 2H, HCp), 6.72 (m, 1H, p-Dip), 6.88 (m, 2H, m-Dip), 7.01-7.19 (m, 15H, CH2Ph), 7.33-7.42 (m, 6H, m-/p-Ph), 7.61 (m, 4H, o-Ph) ppm.
31P-NMR (81.0 MHz, d8-THF): δ=13.2 ppm.
31P-NMR (81.0 MHz, C6D6): δ=14.2 ppm.
A solution of 629 mg [Zr(NMe2)4] (2.35 mmol, 1.00 eq) in 35 mL hexane was cooled to −78° C. and 1.00 mg C5H4PPh2NHDip (2.35 mmol, 1.00 eq) was added portionwise in solid form. It was was warmed to RT and stirred for 12 to 16 hours, whereby a pale yellow solvent and a white precipitate were formed. It was completely concentrated and recrystallized from hexane at −30° C. The white solid is difficult to dissolve in hexane, but soluble in toluene and benzene.
Yield: 904 mg (60%).
CHN: C35H49N4PZr MW: 647.99 g/mol
1H-NMR (300.1 MHz, C6D6): δ=1.14 (d, 3JHH=6.9 Hz, 12H, Me2CH), 2.92 (s, 18H, NMe2), 3.76 (sept, 2H, 3JHH=6.9 Hz, Me2CH), 6.27 (br, m, 2H, HCp), 6.59 (br, m, 2H, HCp), 6.90-7.06 (m, 9H, m-/p-Ph; m-/p-Dip), 7.43 (m, 4H, o-Ph) ppm.
13C-NMR (75.5 MHz, C6D6): δ=24.1 (Me2CH), 28.9 (Me2CH), 45.1 (s, Zr—NMe2), 113.6 (d, 2,3JCP=12.7 Hz, CCp), 117.5 (d, 2,3JCP=12.9 Hz, CCp), 119.9 (d, 5JCP=5.7 Hz, p-Dip), 123.2 (d, 4JCP=2.6 Hz, m-Dip), 128.2 (s, p-Ph), 130.8 (s, m-Ph), 132.0 (d, 2JCP=9.4 Hz, o-Ph), 142.8 (s, o-Dip) ppm.
The signals of the ipso-C atoms cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, C6D6): δ=−12.4 ppm.
EI/MS (70 eV): m/z (%)=425 (14.0) [ligand+], 253 (12.8) [Ph2PCp+], 133 (18.0), 28 (100.0).
IR (Nujol): 2855 [v (N—C)] (s), 1400 [v (P═N)] (s), 702 [v (P—C)] (m), 453 (m), 415 [v (Zr—N)] (s) cm−1.
Crystal Structure Analysis
A solution of 682 mg [Zr(NMe2)4] (2.55 mmol, 1.00 eq) in 30 mL hexane was cooled to −78° C. and 770 mg C5H4PMe2NHDip (2.55 mmol, 1.00 eq) was added portionwise in solid form. It was was warmed to RT for 12 to 16 hours, whereby a white precipitate was formed. It was completely concentrated. The white solid is difficult to dissolve in hexane, but soluble in toluene and benzene.
Yield: 1.21 g (90%).
CHN: C25H50N4PZr MW: 528.89 g/mol
1H-NMR (300.1 MHz, C6D6): δ=1.28 (d, 2JHP=12.0 Hz, PMe2), 1.35 (d, 3JHH=6.8 Hz, 12H, Me2CH), 2.92 (s, 18H, NMe2), 3.76 (sept, 2H, 3JHH=6.8 Hz, Me2CH), 6.09 (br, m, 2H, HCp), 6.42 (br, m, 2H, HCp), 7.08 (t, 1H, 3JHH=7.7 Hz, p-Dip), 7.25 (dd, 2H, 3JHH=7.0 Hz, 5JHP=1.2 Hz, m-Dip) ppm.
13C-NMR (75.5 MHz, C6D6): δ=19.0 (d, 2JCp=62.7 Hz, PMe2), 24.4 (Me2CH), 28.5 (Me2CH), 45.0 (s, Zr—NMe2), 113.3 (d, 2,3JCP=11.5 Hz, CCp), 114.4 (d, 2,3JCP=11.9 Hz, CCp), 119.8 (d, 5JCP=4.1 Hz, p-Dip), 123.1 (d, 4JCP=3.3 Hz, m-Dip), 142.8 (d, 3JCP=7.6 Hz, o-Dip) ppm.
The signal of the ipso-CCp atom cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, C6D6): δ=−11.3 ppm.
EI/MS (70 eV): m/z (%)=301 (23.1) [ligand+], 286 (26.0) [C5H4PMeNDip+], 258 (12.0) [C5H4PMe2N(Me2CHPh)+], 177 (28.3) [NDip+], 162 (100).
IR (Nujol): 2854 [v (N—C)] (s), 1400 [v (P═N)] (m), 671 [v (P-C)] (w), 465 (m), 440 [v (Zr—N)] (s) cm−1.
Crystal Structure Analysis
A solution of 720 mg [Zr(NMe2)4] (2.69 mmol, 1.00 eq) in 50 mL hexane was cooled to −78° C. and 741 mg C5Me4PMe2NHAd (2.69 mmol, 1.00 eq) was added portionwise in solid form. It was was warmed to RT for 12 to 16 hours, whereby a white precipitate had been formed. It was completely concentrated and recrystallized from hexane at −30° C. The white solid is difficult to dissolve in hexane, but soluble in toluene and benzene.
Yield: 1.03 g (69%).
CHN: C25H50N4PZr MW: 528.89 g/mol
1H-NMR (300.1 MHz, C6D6): δ=1.29 (d, 2JHP=11.7 Hz, 6H, PMe2), 1.62 (br, m, 6H, CH2Ad), 1.79 (br, m, 6H, N—C(CH2)3), 2.00 (s, 3H, CHAd), 2.18 (br, m, 6H, C5Me4), 2.32 (br, m, 6H, C5Me4), 3.04 (s, 18H, NMe2) ppm.
13C-NMR (75.5 MHz, C6D6): δ=12.1 (s, C5Me4), 15.3 (s, C5Me4), 21.9 (d, 1JCP=48.6 Hz, PMe2), 30.7 (s, CHAd), 36.8 (s, CH2Ad), 45.1 (s, Zr—NMe2), 46.3 (d, 3JCP=8.5 Hz, NC(CH2)3), 55.5 (d, 2JCP=6.0 Hz, P═N—CAd), 84.4 (s, ipso-CCp) 120.9 (d, 2,3JCP=9.4 Hz, C(Me)═C(Me)), 126.4 (d, 2,3JCP=12.8 Hz, C(Me)═C(Me)) ppm.
31P-NMR (81.0 MHz, C6D6): δ=13.3 ppm.
EI/MS (70 eV): m/z (%)=332 (3.6) [ligand+], 269 (2.8), 227 (42.6), 211 (19.0) [Me2PNAd+], 196 (18.8) [MePNAd+], 170 (100.0), 150 (65.7) [AdN+], 136 (14.9) [Ad+].
IR (Nujol): 2854 [v (N—C)] (s), 2761 (w), 1399 [v (P═N)] (m), 1294 (w), 1282 (w), 1282 (w), 1034 (s), 902 (w), 777 [v (P—C)] (m), 679 (w), 646 (m), 534 (m), 482 [v (Zr—N)] (m) cm−1.
Crystal Structure Analysis
A solution of 256 mg [Zr(NMe2)4] (0.96 mmol, 1.00 eq) in 20 mL Et2O was cooled to −78° C. and 500 mg CpH™ PPh2NDip (0.96 mmol, 1.00 eq) was added portionwise in solid form. It was was warmed to RT for 12 to 16 hours, whereby the colorless solvent took a pale green color. It was reduced to dryness and the pale green remainder dissolved in 20 mL THF. The solvent was heated to 50° C. for 3 days.
31P-NMR (81.0 MHz, 1. Et2O, 2. THF): δ=1. after stirring during 12 to 16 hours in Et2O: 2.3 (35%), −14.8 (65%) [ligand] ppm; 2. after stirring for 3 d in THF at 50° C.: five signals, main signal at −14.5 (49%) [ligand] ppm.
A solution of 270 mg [Zr(NMe2)4] (1.01 mmol, 1.00 eq) in 20 mL Et2O was cooled to −78° C. and 500 mg Cp™ PPh2NHAd (1.01 mmol, 1.00 eq) was added portionwise in solid form. It was warmed to RT during 12 to 16 hours, whereby a grey precipitate precipitated from the black solvent. It was reduced to dryness and the dark grey remainder was dissolved in 20 mL THF. The solvent was heated to 50° C. for 3 days.
31P-NMR (81.0 MHz, 1. Et2O, 2. C6D6): δ=1. after stirring for 12 to 16 hours in Et2O: 16.7 (100%) [ligand] ppm; 2. after stirring for 3 d in THF at 50° C.: 16.7 (100%) [ligand] ppm.
377 mg (1.00 mmol, 1.00 eq) LiCH2SiMe3 was added in solid form at 0° C. to a suspension of 377 mg ZrCl4(thf)2 (1.00 mmol, 1.00 eq) in 10 mL hexane/Et2O=1:1 and kept at 0° C. under stirring for 2 h. Thereby, a white precipitate was formed. Subsequently, 426 mg C5H4PPh2NHDip (1.00 mmol, 1.00 eq) was added in solid form at 0° C. and the reaction mixture was warmed to RT during 12 to 16 hours. Thereby, the suspension color changed from yellow into grey-green. It was reduced to half of the initial volume, filtered over Celite and the white remainder washed with 10 mL hexane. The filtrate was reduced to dryness. Thereby, a orange-colored oil was obtained. By recrystallization from hexane at −80° C. 252 mg of a white solid was obtained (yield 32%).
1H-NMR (300.1 MHz, C6D6): δ=0.20 (s, 27H, Si(CH3)3), 0.89 (s, 6H, Zr—CH2—Si), 1.11 (d, 3JHH=7.0 Hz, 12H, Me2CH), 3.69 (sept, 2H, 3JHH=7.4 Hz, Me2CH), 6.43 (m, 2H, HCp), 6.65 (m, 2H, HCp), 6.99 (m, 6H, m-/p-Ph), 7.03 (m, 2H, m-Dip), 7.13 (m, 1H, p-Dip), 7.42-7.49 (m, 4H, o-Ph) ppm.
31P-NMR (81.0 MHz, C6D6): δ=−10.9 ppm.
To a suspension of YCl3(thf)3 (411 mg, 1.00 mmol), THF (0.3 mL, 3.7 mmol) and [η5:η1-C5H4PPh2NHDip] (425 mg, 1.00 mmol) in diethyl ether (30 mL), a solution of LiCH2SiMe3 (286 mg, 3.04 mmol) in hexane (15 mL) was added dropwise at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 1.5 h at 0° C. Subsequently, the LiCl formed during the reaction was filtered off. The solvent was drawn off and the remainder extracted with hexane. Crystallization at −30° C. resulted in a white microcrystalline solid. Yield: 34% (231 mg).
1H-NMR (300.1 MHz, C6D6): δ=−0.48 (br. s, 4H, CH2TMS), 0.46 (s, 18H, CH2TMS), 0.74 (br. s, 12H, Me2CH), 1.14 (m, 4H, THF), 3.18 (sept, 3JHH=6.8 Hz, 2H, Me2CH), 3.66 (m, 4H, THF), 6.74 (m, 2H, Cp), 6.90-7.00 (m, 9H, Ar), 7.09 (m, 2H, Cp), 7.47 (m, 4H, o-Ph) ppm.
13C{1H} NMR (75.5 MHz, C6D6): δ=4.6 (TMSCH2), 24.5 (br, s, Me2CH), 24.9 (THF), 29.0 (CHMe2), 31.6, 32.1 (CH2TMS), 70.1 (THF), 94.5 (d, J=125 Hz, ipso-Cp), 115.5 (d, J=13.5 Hz, Cp), 119.0 (d, J=14.4 Hz, Cp), 124.2 (d, J=4.0 Hz, p-Dip), 124.4 (d, J=3.5 Hz, m-Dip), 128.4(d, J=12 Hz, m-Ph), 129.5 (d, J=88 Hz, ipso-Ph), 132.3 (d, J=2.9 Hz, p-Ph), 133.1 (d, J=9.6 Hz, o-Ph), 141.4 (d, J=9.8 Hz, ipso-Dip), 145.2 (d, J=6.4 Hz, o-Dip), 188.1 ppm.
31P{1H} NMR (81.0 MHz, C6D6): δ=9.6 (s) ppm.
Elementary analysis: Calculated for C41H59NOPSi2Y (757.99): C 64.97, H 7.85, N 1.85. Found: C 64.56, H 7.80, N 1.90.
The production takes place analogously to the procedure described in embodiment 1.
To a suspension of YCl3(dme)2 (275 mg, 1.00 mmol) and [η5:η1-C5Me4PMe2NHAd] (330 mg, 1.00 mmol) in diethyl ether (20 mL), a solution of LiCH2SiMe3 (290 mg, 3.08 mmol) in hexane (20 mL) was added dropwise at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 1.5 h at 0° C. Subsequently, the LiCl formed during the reaction was filtered off. The solvent was drawn off and the remainder extracted with hexane. Crystallization at −30° C. resulted in a white microcrystalline solid. Yield: 58% (343 mg).
1H (300.1 MHz, C6D6) −0.70, −0.75 (2*dd, 2*2H, 2JHY=3.0 Hz, 2JHH=11 Hz, ABX system), 0.40 (s, 18H, 2*SiMe3), 1.13 (d, 6H, 2JHP=12.5 Hz, Me2P), 1.56 (m, 6H, Ad), 1.71 (m, 6H, Ad), 2.00 (m, 3H, Ad), 2.03 (s, 6H, Me4C5), 2.12 (s, 6H, Me4C5).
13C{1H} (75.5 MHz, C6D6) δ=4.7 (s, SiMe3), 11.4 (s, Me-C═C-Me), 13.9 C═C-Me), 21.9 (d, 1JCP=55 Hz, Me2P), 30.2 (s, HC(CH2)3), 31.4 (d, 1JCY=34 Hz,
Y—CH2Si) 36.3 (s, CH2(CH)2), 47.6 (d, 2JCP=9.1 Hz, NC(CH2)3), 54.2 (s, 1JCP=7.5 Hz, N—CAd), 84.6 (d, 1JCP=116 Hz, Me2P—Cipso), 121.8 (d, JCP=13 Hz, Me2C—CMe2), 123.7 (d, JCP=16 Hz, Me2C—CMe2) ppm.
31P{1H} NMR (81.0 MHz, C6D6): δ=14.7 ppm.
Elementary analysis: Calculated for C29H55NPSi2Y (593.82): C 58.66, H 9.34, N 2.36. Found: C 59.21, H 9.71, N 2.41.
The production takes place analogously to the procedure described in embodiment 1.
To a suspension of ScCl3(thf)3 (367 mg, 1.00 mmol) and [η5:η1-C5Me4PMe2NHAd] (330 mg, 1.00 mmol) in diethyl ether (20 mL), a solution of LiCH2SiMe3 (290 mg, 3.08 mmol) in hexane (20 mL) was added dropwise at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 1.5 h at 0° C. Subsequently, the LiCl formed during the reaction was filtered off. The solvent was drawn off and the remainder extracted with hexane. Crystallization at −30° C. resulted in a white microcrystalline solid. Yield: 42% (231 mg).
1H NMR (300.1 MHz, C6D6): δ=−0.40 (d, AB-system, 2JHH=11.2 Hz, 2H, CH2SiMe3), −0.37 (d, AB-System, 2JHH=11.2 Hz, 2H, CH2SiMe3), 0.36 (s, 18H, 3*CH2SiMe3), 1.17 (d, 2JHP=12.5 Hz), 1.60 (m, 6H, NC(CH2)3), 1.83 (m, 6H, CH2(CH)2), 2.01 (s, 6H, C5Me4), 2.02 (m, 3H, CH(CH2)3), 2.14 (s, C5Me4) ppm.
13C{1H} NMR (75.5 MHz, C6D6): δ=4.5 (s, SiMe3), 12.0 (d, J=6.9 Hz, C5Me4), 14.4 (C5Me4), 21.6 (d, 2JCP=55 Hz, Me2P), 30.4 (CH(CH2)3), 36.5 (CH2(CH)2), 47.2 (d, J=8.7 Hz, NC(CH2)3), 54.6 (d, J=6.8 Hz NC), 84.8 (d, 1JCP=114 Hz, ipso-C5Me4), 122.5 (d, J=13.3 Hz, C5Me4), 125.7 (d, J=14.4 Hz, C5Me4) ppm.
31P{1H} NMR (81.0 MHz, C6D6): δ=12.0 (s) ppm
Elementary analysis: Calculated for C29H55NPScSi2 (549.87): C 63.35, H 10.08, N 2.55. Found: C 62.92, H 9.78, N 2.41.
The production takes place analogously to the procedure described in embodiment 1.
To a suspension of ScCl3(thf)3 (367 mg, 1.00 mmol) and [η5:η1-C5H4P Ph2NHDip] (425 mg, 1.00 mmol) in diethyl ether (20 mL), a solution of LiCH2SiMe3 (290 mg, 3.08 mmol) in hexane (20 mL) was added dropwise at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 1.5 h at 0° C. Subsequently, the LiCl formed during the reaction was filtered off. The solvent was drawn off and the remainder extracted with hexane. Crystallization at −30° C. resulted in a white microcrystalline solid. Yield: 32% (206 mg).
1H NMR (300.1 MHz, C6D6): δ=0.12 (br, s, 2H, CH2SiMe3), 0.25 (br, s, 2H, CH2SiMe3), 0.37 (s, 18H, CH2SiMe3), 1.25 (br, s, 12H, Me2CH), 3.42 (sept, 3JHH=6.8 Hz, 2H, Me2CH), 6.77 (m, 2H, C5H4), 8.85-7.09 (m, 11H, C5H4, Ph, Dip), 7.41 (m, 4H, o-Ph) ppm.
13C{1H} NMR (75.5 MHz, C6D6): δ=3.9 (s, CH2SiMe3), 23.5 (br, s, Me2CH), 26.3 (br, s, Me2CH), 28.8 (s, Me2CH), 42.2 (br, s, CH2TMS), 92.7 (d, J=121 Hz, ipso-C5H4), 118.3 (d, J=12.9 Hz, C5H4), 119.2 (d, J=14.2 Hz, C5H4), 124.8 (d, J=3.4 Hz, m-Dip), 125.3 (d, J=3.9 Hz, p-Dip), 127.7 (d, J=90 Hz, ipso-Ph) 128.7 (d, J=12.3 Hz, m-Ph), 132.8 (d, J=2.8 Hz, p-Ph), 133.5 (d, J=9.9 Hz, o-Ph), 139.9 (d, J=9.3 Hz, ipso-Dip), 145.8 (d, J=6.1 Hz, o-Dip) ppm.
31P{1H} NMR (81.0 MHz, C6D6): δ=12.1 (s) ppm
Elementary analysis: Calculated for C37H53NPScSi2 (643.94): C 69.01, H 8.30, N 2.17. Found: C 68.71, H 8.59, N 2.10.
To a mixture of NdBr3(thf)4 (672.3 mg, 1.00 mmol) and [η5:η1-C5H4PMe2NHDip] (331 mg) in diethyl ether (15 mL), a solution of LiCH2SiMe3 (290 mg, 3.08 mmol) in toluene (15 mL) was added dropwise within 15 min at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 15 min and subsequently reduced to ⅓ of its original volume. The obtained precipitate is removed by filtration over Celite. The transparent green solution is left standing at −30° C. to crystallize. Subsequently, 15 mL hexane was added and the formed blue precipitate was filtered off.
Yield: 7.6% (55 mg, 0.076 mmol). The green substance is strongly paramagnetic; the characterization took place by means of monocrystal XRD.
Elementary analysis: Calculated for C31H57NNdOPSi2 (691.19): C 53.87, H 8.31, N 2.03. Found: C 51.10, H 10.23, N 1.70.
The production takes place analogously to the procedure described in embodiment 5.
To a mixture NdCl3(dme) (340 mg, 1.00 mmol) and [η5:η1-C5Me4PMe2NHAd] (340 mg, 1.03 mmol) in diethyl ether (15 mL), a solution of LiCH2SiMe3 (290 mg, 3.08 mmol) in toluene (15 mL) was added dropwise within 15 min at 0° C. After completed addition of LiCH2SiMe3 the solution was stirred for another 15 min and subsequently reduced to ⅓ of its original volume. The obtained precipitate is removed by filtration over Celite. The transparent green solution is left standing at −30° C. to crystallize. Subsequently, 15 mL hexane was added and the formed microcrystalline blue precipitate was filtered off. Yield: 49% (315 mg, 0.49 mmol).
1H NMR (300.1 MHz, C6D6): δ=−21.72 (s, 6H, Me4C5), −13.52 (s, 6H, Me4C5), −5.83 (d, 2JHH=10 Hz, 3H, HCH(CH)2), −4.94 (s, 3H, CH(CH2)2), −3.62 (d, 2JHH=10 Hz, 3H, HCH(CH)2), 2.62 (s, 18H, SiMe3), 10.58 (d, 2JHP=13 Hz, 6H, Me2P), 11.45 (s, 6H, CH2CN), 20.22 (br, s, 2H CH2Si), 29.45 (br, s, 2H CH2Si) ppm.
Elementary analysis: Calculated for C29H55NNdPSi2 (649.15): C 53.66, H 8.54, N 2.16. Found: C 51.70, H 7.90, N 1.82.
Some of the CG-CpPN complexes of the zirconium, according to the present invention, were used as catalysts for the intramolecular hydroamination of ω-alkenes. 2,2-diphenyl-pent-4-amine was used as a substrate:
The catalysis experiments are hereinafter represented in the form of a table:
The examinations show that neutral CG complexes of zirconium together with the CpPN ligands are active in the intramolecular hydroamination of 2,2-diphenyl-pent-4-en-1-amine.
By way of example, catalysis studies concerning the intramolecular hydroamination of ω-aminoalkenes are listed. The reactions are carried out at 25° C. and monitored via 1H-NMR-spectroscopy in C6D6 or by quantitative GC as well. 2,2-Diphenyl-pent-4-en-1-amine and 2,2-Diphenyl-pent-4-en-1-amine are used as standard substrates. The selectivity of the cyclisation is 100% with all catalysts used. This means that the indicated yields correspond to the respective conversions after the time t (first column):
The TOF values are in the range which is usual for hydroaminations with CG catalyst of the rare-earth metals with the classical CpSiN ligands [(C5Me4SiMe2NtBu)Ln(R1)(thf)] [Ref: T. J. Marks et al., Organometallics 1999, 18, 2568-2570].
Here, TOF stands for “turnover frequency”.
22.98 mg [(η5:η1-C5H4PMe2NDip)Zr(CH2SiMe3)3] (35.18 μmol, 1.00 eq) and 23.5 mg B(C6F5)3 (45.90 mmol, 1.95 eq) were weighed in an NMR tube and dissolved in 0.6 mL C6D6. The reaction mixture was shaken for 30 sec at RT. Hereby, two phases, immiscible with one another, were formed. The benzene phase was drawn off with the help of a syringe and the remaining, pale yellow ionic liquid was examined using NMR spectroscopy. The liquid is stable at RT for several days.
1H-NMR (300.1 MHz, CD2Cl2): δ=0.26 (s, 9H, Si(CH3)3), 0.27 (s, 9H, Si(CH3)3), 0.30 (d, 4JBH=12.5 Hz, 9H, BCH2Si(CH3)3), 0.89 (br, s, 2H, BCH2Si(CH3)3), 1.04 (d, 2JHH=10.7 Hz, 2H, Zr—CH2—Si), 1.42 (d, 3JHH=6.9 Hz, 12H, Me2CH), 1.44 (d, 2JHH=11.1 Hz, 2H, Zr—CH2—Si), 1.97 (d, 2JHP=12.3 Hz, PMe2), 2.78 (sept, 2H, 3JHH=6.6 Hz, Me2CH), 7.08 (br, m, 2H, HCp), 7.27 (br, m, 2H, HCp), 7.40 (d, 3JHH=7.8 Hz, 2H, m-Dip), 7.50 (br, m, 1H, p-Dip) ppm.
13C-NMR (75.5 MHz, CD2Cl2): δ=1.3 (s, Si(CH3)3), 2.2 (s, Si(CH3)3), 3.2 (s, BCH2Si(CH3)3), 13.2 (d, 1 JCP=59.1 Hz, PMe2), 24.8 (s, BCH2Si(CH3)3), 26.3 (Me2CH), 26.4 (Me2CH), 28.7 (s, Me2CH), 80.3 (s, Zr—CH2—Si), 81.4 (s, Zr—CH2—Si), 117.7 (d, 2,3JCP=13.6 Hz, CCp), 117.9 (d, 2,3JCP=13.1 Hz, CCp), 118.8 (d, 2,3JCP=12.8 Hz, CCp), 119.1 (d, 2,3JCP=13.6 Hz, CCp), 126.7 (s, p-Dip), 129.1 (d, 4JCP=3.6 Hz, m-Dip), 145.6 (d, 3JCP=6.4 Hz, o-Dip) ppm.
The signals of the carbon atoms of the perfluorinated aryl ring cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, CD2Cl2): δ=27.4 ppm.
19F-NMR (188.3 MHz, CD2Cl2): δ=−135.4 (d, 3JFF=24.5 Hz), −167.5 (t, 3JFF=20.7 Hz), −170.1 (t, 3JFF=21.2 Hz) ppm.
29.39 mg [(η5:η1-C5H4PMe2NDip)Zr(CH2SiMe3)3] (44.99 μmol, 1.00 eq) and 37.76 mg Me2NHPh+B(C6F5)4− (47.13 mmol, 1.05 eq) were weighed in an NMR tube and dissolved in 0.6 mL C6D6. The reaction mixture was shaken for 30 sec at RT. Hereby, two phases, immiscible with one another, were formed. The benzene phase was drawn off with the help of a syringe and the remaining, yellow-green ionic liquid was examined using NMR spectroscopy. The liquid is stable at RT for several days.
1H-NMR (300.1 MHz, CD2Cl2): δ=0.18 (s, 18H, Si(CH3)3), 0.98 (s, 2H, Zr—CH2—Si), 1.35 (d, 3JHH=6.6 Hz, 12H, Me2CH), 1.36 (d, 2JHH=10.7 Hz, 2H, Zr—CH2—Si), 2.00 (d, 2JHP=12.6 Hz, PMe2), 2.73 (sept, 2H, 3JHH=6.9 Hz, Me2CH), 7.06 (m, br, 2H, HCp), 7.25 (m, br, 2H, HCp), 7.35 (d, 3JHH=7.8 Hz, 2H, m-Dip), 7.43 (m, br, 1H, p-Dip) ppm.
13C-NMR (75.5 MHz, CD2Cl2): δ=2.3 (s, Si(CH3)3), 13.6 (d, 1JCP=59.1 Hz, PMe2), 25.1 (Me2CH), 26.5 (Me2CH), 29.0 (s, Me2CH), 80.2 (s, Zr—CH2—Si), 117.7 (d, 2,3JCP=13.0 Hz, CCp), 118.9 (d, 2,3JCP=13.4 Hz, CCp), 128.6 (s, 5JCP=3.0 Hz, m-Dip), 128.9 (d, 4JCP=3.4 Hz, p-Dip), 145.5 (d, 3JCP=5.2 Hz, o-Dip) ppm.
The signals of the carbon atoms of the perfluorinated aryl ring cannot be observed in the 13C-NMR spectrum.
31P-NMR (81.0 MHz, CD2Cl2): δ=27.4 ppm.
19F-NMR (188.3 MHz, CD2Cl2): δ=−135.5 (s, br), −166.0 (s, br), −169.9 (t, 3JFF=20.7 Hz) ppm.
The polymerization of ethene was carried out in a 250 mL Two-neck Schlenk flask at a temperature of 50° C. and a pressure of 1 atm. The ethene was freed from oxygen via a column over a Cu catalyst (R3-11G-Kat., BASF) and subsequently via a second column with molecular sieve 3 Å from traces of water. The reaction vessel was flushed with a solution of triisobutylaluminum (TIBA) in 145 mL at RT to remove traces of possibly absorbed water. Due to its function as scavenger, the triisobutylaluminum remained in the reaction vessel during the polymerization. Ethene was passed through the solution during approx. 20 min to generate a saturated solution. Using glove box, approx. 50 μmol (1.0 eq) of the catalyst was dissolved in 5 mL toluene and activated by reaction with approx. 75 μmol (1.5 eq) B(C6F5)3 (BCF). Subsequently, the active catalyst species was added all at once to the toluene solution of TIBA saturated with ethene and heated to 50° C. With all tested catalysts, heat generation occurred immediately after addition of the cationic species. The solution became instantly more viscous and after a few minutes polyethene precipitated in the form of a white solid. The reaction was stopped after 30 min by addition of 20 mL of a 5% solution of HCl in ethanol. The content of the reaction vessel was added to 200 mL of a 5% solution of HCl in ethanol. The formed polyethylene was filtered off after 2 h, washed with ethanol and dried in the drying cabinet at 100° C.
Since the activity of a catalyst depends very strongly on the reaction conditions, Eurocene 5031 [ZrIV(nBuCp)2Cl2], which is active in polymerization catalysis, was used under similar conditions for an appropriate comparison. For this purpose, 25 mmol MAO in 245 mL toluene was provided and flushed with ethane for 20 min. Using the glove box, 50 μmol of the catalyst was dissolved in 5 mL toluene and added all at once to the toluene solution of methylaluminoxane (MAO) saturated with ethene. The reaction was stopped after 30 min by addition of 20 mL of a 5% solution of HCl in ethanol. The content of the reaction vessel was added to 200 mL of a 5% solution of HCl in ethanol. The formed polyethylene was filtered off after 2 h, washed with ethanol and dried in the drying cabinet at 100° C.
Tested Catalysts
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2007 057 854.9 | Nov 2007 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/DE08/01942 | 11/25/2008 | WO | 00 | 10/25/2010 |
