Patent Application
20210163514
The present application relates to the technical field of organic chemistry, and relates to a novel compound of 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand, an intermediate, a preparation method and a use of the ligand compound. The ligand can be used for coupling reaction or asymmetric catalytic reaction.
Asymmetric catalytic synthesis is currently one of the most active research fields in chemical science. It is the most direct and effective method to obtain optically active molecules. It has advantage of chiral proliferation, high enantioselectivity, economic efficiency, and convenience of industrialization. It is a challenging topic in the field of synthetic chemistry to achieve asymmetric catalytic synthesis reactions with high-efficiency and high-selectivity, and one of the pivotal scientific issues is to develop and discover new highly effective chiral ligands and their catalysts. The design and synthesis of chiral ligands have been rapidly developed, and many excellent chiral ligands have been synthesized as follows, some of which have been adopted in the industrial production. However, there are still many problems, such as limited applicability of ligands, and high dependence on reaction substances, and absence of a universal chiral ligand. Therefore, it is always urgent to search for new highly effective and highly selective chiral ligands in the chiral synthesis.
The synthesis design of chiral ligands (for improving catalytic activity stereoselectivity) follows certain rules, mainly considering electrical and structural factors such as dihedral angle, steric hindrance and skeleton rigidity, etc. It is currently believed that the dihedral angle has a significant influence on the stereoselectivity of asymmetric catalysis (Acc. Chem. Res. 2007, 40, 1385-4393, [FIG. 2]; Tetrahedron: Asymmetry 15 (2004) 2185-2188; EP1002801, U.S. Pat. No. 6,333,291; J. Org. Chem. 1999, 65, 6223; CN 1331871C; J. Org. Chem. 2000, 65, 6223; J. AM. CHEM. SOC. 2006, 128, 5955). In addition, bisphosphine ligands containing electron-withdrawing substituents often greatly improve the reaction yield, or improve the enantioselectivity, or change the regioselectivity of the reaction or provide the opposite ring-closed stereoselectivity (J. Am. Chem. Soc., 2009, 131 (28), pp 9604; Adv. Synth. Catal. 2017, 359, 2762; Angew. Chem. Int. Ed. 2017, 56, 9541; Chemistry—A European Journal (2015), 21(12), 4561).
In 1999, Birman et al. synthesized and obtained racemic 1,1′-spirobiindane-7,7′-diol SPINOL from m-methoxybenzaldehyde via a six-step reaction, and obtained the corresponding optical enantiomer through chemical resolution (Tetrahedron: Asymmetry 1999, 10, 12), and it indicated that the compound may be used to synthesize various chiral ligands However, according to such a scheme or other published methods, it is obviously impossible to obtain the corresponding 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-7,7′-diol. In 2003, using the optically active 1,1′-spirobiindane-7,7′-diol SPINOL as raw material, Zhou Qilin et al. synthesized a 1,1′-spirobiindane-based bisphosphine ligand SDP through a five-step reaction, which was successfully used in the asymmetric catalytic hydrogenation (CN1439643). However, according to their synthetic scheme based on a coupling reaction, it is still impossible to obtain a diphosphine ligand in which the phenyl on the phosphorus atom is substituted with electron-withdrawing group (substitutents such as p-trifluoromethyl and 3,5-bis(trifluoromethyl)) (Nankai University, 2003, page 26 of doctoral dissertation “Researches on scheme design synthesis and application of chiral spiro-diphosphine ligand”, XIE Jianhua; J. AM CHEM SOC. 2003, 125, 4404-4405); and starting from the industrially available raw material m-methoxybenzaldehyde, the corresponding 1,1′-spirobiindane-based chiral disphosphine ligand SDP was obtained through at least 11 steps of synthesis reaction and 1 step of chiral resolution, which has lengthy reaction steps, increased costs, and significantly reduced practicability.
It was reported in 1962 that 6,6′-dihydroxyl-3,3,3′,3′-tetramethyl-1,1′-spirobiindane (MSPINOL) could be obtained with high yields through acid catalysis directly of from bisphenol series products, and the modified large-scale preparation methods and chiral resolution methods were subsequently reported (referring to the following reaction equation, J. Chem. Soc., 1962, 415-418; Org. Lett., 2004, 6, 2341-2343; US2006/0020150; U.S. Pat. No. 4,879,421; Bull. Chem. Soc. Japan, 1977, 44, 496-505):
3,3,3′,3′-tetramethyl spirobiindane-6,6′-diphenol MSPINOL and its derivatives are known to be mainly used for preparing polymers, but they have not been used for the preparation or application of any ligands. The corresponding raw material, bisphenol, is very cheap and can be prepared by condensation reaction of acetone and phenol or its derivatives. In addition, many industrial bisphenol series products (bisphenol A, bisphenol C, etc.) are available and on large-scale sales, for example, the annually produced and sold bisphenol A in the world are as high as more than 3 million tons, with a price less than 10,000 RMB per ton. The present application is intended to utilize cheap and easily available 3,3,3′,3′-tetramethyl spirobiindane-6,6′-diphenol to design and prepare the corresponding 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand. Compared with 1,1′-spirobiindane-based phosphine ligand such as SDP, such a kind of ligands has no active aryl methylene group on the spiro ring skeleton, the 3,3,3′,3′-tetramethyl-1,1′-spirobiindane skeleton is more stable and has stronger rigidity, the raw materials thereof are cheap and abundant, the synthesis scheme is shorter, the preparation cost is low, the practicability is high, and the unique dihedral angle indicates different catalytic effects or uses. Particularly, the phosphine ligands, in which the phenyl group on the phosphorus atom is substituted with an electron-withdrawing group (such as trifluoromethyl, 3,5-bis (trifluoromethyl) and other substituents, can be prepared according to the present application, thereby greatly enriching the phosphine ligand derivatives. Based on the method disclosed in the present application, the 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand is generally prepared with the industrial large-tonnage raw material bisphenol via a five-step synthesis reaction scheme:
or
prepared via a seven-step synthesis reaction scheme:
The present application provides a compound of 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand, an intermediate, a preparation method and a use thereof.
A 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand is a compound represented by general I or formula II, or is an enantiomer, a raceme or a diastereomer thereof:
In the formulas: R1 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, aryloxy or substituted aryloxy, heteroaryloxy or substituted heteroaryloxy, aryl or substituted aryl, and heteroaryl or substituted heteroaryl; R2, R3, R4, and R5 are each independently selected from the group consisting of hydrogen, halogen, C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, aryloxy or substituted aryloxy, heteroaryloxy or substituted heteroaryloxy, aryl or substituted aryl, and heteroaryl or substituted heteroaryl; and R7 is selected from the group consisting of C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C6-C14 aryl, substituted aryl, C5-C14 heteroaryl, and substituted heteroaryl; and the substituted aryloxy, the substituted aryl or the substituted heteroaryl contains one or more substituents independently selected from the group consisting of halogen, N-dimethylamino, C1-C4 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, methylenedioxy, C6-C14 aryl, aryloxy, and heteroaryl; and heteroaryl is C5-C14 heteroaryl.
An intermediate compound for preparing the 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand is a compound represented by general formula III, or an enantiomer, a raceme or a diastereomer thereof:
In the formula: R1 and R6 are each independently selected from the group consisting of hydrogen, hydroxyl, C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, aryloxy or substituted aryloxy, heteroaryloxy or substituted heteroaryloxy, aryl or substituted aryl, and heteroaryl or substituted heteroaryl; and R2, R3, R4, and R5 are each independently selected from the group consisting of hydrogen, halogen, C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, aryloxy or substituted aryloxy, heteroaryloxy or substituted heteroaryloxy, aryl or substituted aryl, and heteroaryl or substituted heteroaryl; and the substituted aryloxy, the substituted aryl or the substituted heteroaryl contains one or more substituents independently selected from the group consisting of halogen, C1-C4 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, methylenedioxy, aryl, aryloxy, and heteroaryl; the heteroaryl is C5-C14 heteroaryl; and X is halogen.
The 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand represented by formula I is preferably any one of the following compounds:
The 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand represented by formula II is preferably any one of the following compounds:
The intermediate represented by formula III of the 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based phosphine ligand is preferably any one of the following compounds:
In the compound represented by formula I and the compound represented by formula II, R7 is selected from the group consisting of phenyl, benzyl, pentafluorophenyl, 4-methylphenyl, 4-methoxyphenyl, 4-trifluoromethyl-phenyl, 3,5-dimethylphenyl, 3,5-difluorophenyl, 3,5-dimethoxyphenyl, 3,5-di-tert-butylphenyl, 3,4,5-trimethoxyphenyl, 3,5-dimethyl-4-methoxy-phenyl, 3,5-di-tert-butyl-4-methoxy-phenyl, 3,5-dimethyl-4-methoxy-phenyl, and 3,5-bis(trifluoromethyl)-phenyl.
The intermediate compound represented by formula III can be prepared by using racemic or optically active 6,6′-dihydroxyl-3,3,3′,3′-tetramethyl-1,1′-spirobiindane represented by formula 1 as a starting material, through the following reactions: the compound represented by formula 1 (when R2 and R5 are not hydrogen) is first subjected to a halogenation reaction to obtain the compound 2, or the compound represented by formula 1 (when at least one of R2 and R5 is hydrogen) is subjected to tert-butylation, halogenation reaction and de-Cert-butylation reaction to obtain the compound 2; the compound 2 is subjected to etherification reaction to prepare and obtain the compound shown as formula III, or the compound 2 is first subjected to esterification using trifluoromethanesulfonic anhydride, and then to palladium-catalyzed coupling reaction or reduction reaction to prepare and obtain the compound shown as formula III;
In the formulas 1, 2, 3, 4, and 5, X and R1-R6 are the same as in the formula III, and R is selected from the group consisting of C1-C10 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, aryl or substituted aryl, and heteroaryl or substituted heteroaryl. The substituted aryl or the substituted heteroaryl contains one or more substituents independently selected from the group consisting of halogen, C1-C4 alkyl or perfluoroalkyl, C3-C6 cycloalkyl, C1-C4 alkoxy or perfluoroalkoxy, methylenedioxy, aryl, aryloxy, and heteroaryl; and the heteroaryl is C5-C14 heteroaryl.
A synthesis method thereof is as follows: when one of R2 and R5 is hydrogen, the step of preparing compound 2 from compound 1 includes the following steps: in dichloromethane or chloroform, in the presence of methanesulfonic acid, the compound 1 reacts with tert-butanol for 2-6 hours at temperature controlled at 0° C. to 40° C., to obtain an intermediate 4; in dichloromethane or ethyl acetate, the intermediate 4 reacts with a halogenated reagent under the catalysis of p-toluenesulfonic acid for 12-24 hours at temperature controlled at 0° C. to 40° C., so as to obtain an intermediate 5; and in toluene or dichloromethane, the intermediate 5 is treated with trifluoromethanesulfonic acid for 1-48 hours to obtain an intermediate 2, in which a molar ratio of the compound 1, the tert-butanol and the methanesulfonic acid is 1:2-4:5-12, a molar ratio of the intermediate 4, the halogenated reagent and the p-toluenesulfonic acid is 1:2-4:0-1, and a molar ratio of the intermediate 5 and the trifluoromethanesulfonic acid is 1:0.8-3;
when none of R2 and R5 is hydrogen, the step of the halogenation reaction for preparing 2 from the compound 1 is that in dichloromethane or ethyl acetate, the compound 1 reacts with the halogenated reagent under catalysis of p-toluenesulfonic acid for 12-24 hours, with the temperature being controlled at 0° C. to 40° C., to obtain the intermediate 2, in which the molar ratio of the compound 1, the halogenated reagent and the p-toluenesulfonic acid is 1:2-4:0-1;
the halogenated reagent may be N-halogenated succinimide, dibromohydantoin, iodine chloride, bromine, chlorine, or N-fluorodiphenylsulfonamide;
when R1 and R6 are hydroxyl, the compound represented by formula III is the compound 2;
the step of the etherification reaction for preparing the compound III from the compound 2 (R1 and R6 are not hydroxyl) is that in N, N-dimethylformamide, dioxane, acetone or dimethyl sulfoxide, in the presence of an alkali, using cuprous iodide as a catalyst, with the temperature being controlled at 25° C. to 100° C., the compound 2 reacts with an etherification reagent RX for 6-36 hours to obtain the compound represented by formula III, in which the alkali may be one or more, in any ratio, of potassium hydroxide, sodium hydroxide, potassium carbonate, cesium carbonate, sodium carbonate, proline, or N, N-dimethylglycine, a molar ratio of the compound 2, the alkali and the cuprous iodide is 1:0.1-5:0-0.2, a molar ratio of the compound 2 and the etherification reagent RX is 1:2-4;
the step of the esterification for preparing the compound 3 from the compound 2 is that in dichloromethane or dichloroethane, in the presence of an alkali, the compound 2 reacts with trifluoromethanesulfonic anhydride for 0.2-6 hours at a temperature controlled at 0° C. to 40° C., to obtain the compound 3, in which the alkali may be one or more, in any ratio, of pyridine, triethylamine, potassium hydroxide, or sodium hydroxide, and a molar ratio of the compound 2, the alkali and the trifluoromethanesulfonic anhydride is 1:2-8:2-6;
the step of the reduction reaction for preparing the compound III from the compound 3 is that in N,N-dimethylformamide, dioxane or dimethyl sulfoxide, in the presence of an organic base, using bis(triphenylphosphine) palladium dichloride and 1,3-bis(diphenylphosphino)propane as a catalyst system, the compound 3 reacts with formic acid for 1-6 hours at a temperature controlled at 25° C. to 100° C., to obtain the compound III, in which a molar ratio of the compound 3, the formic acid, the organic base, the bis(triphenylphosphine) palladium dichloride and the 1,3-bis(diphenylphosphino)propane is 1:2-6:8-15:0.05-0.2:0.05-0.2; and the organic base is triethylamine, tripropylamine or tributylamine; and
the step of the coupling reaction for preparing the compound III from the compound 3 is that in N,N-dimethylformamide, dioxane, water, acetone, dimethyl sulfoxide or a mixed solvent thereof in any ratio, in the presence of an alkali and a metal catalyst, the compound 3 reacts with a coupling reagent RB(OH)2 for 6-36 hours while the temperature is controlled at 25° C. to 100° C., to obtain the compound represented by formula III, in which the alkali may be one or more, in any ratio, of potassium hydroxide, sodium hydroxide, potassium carbonate, cesium carbonate, or sodium carbonate, a molar ratio of the compound 3; a molar ratio of the compound 3, the alkali and the metal catalyst is 1:0.1-5:0.05-0.2, a molar ratio of the compound 3 and the coupling reagent RB(OH)2 is 1:2-4, the metal catalyst is at least one or more, in any ratio, of Pd(OAc)2, Pd(PPh3)4, PdCl2, Pd(PPh3)2Cl2, Pd2(dba)3, CuI, or dpppNiCl2.
A synthesis method of the compound I is as follows: a racemic or optically active compound represented by formula III, as a raw material, reacts with a di-substituted phosphine halide under an effect of an alkali and the compound represented by formula I is prepared through a double-substitution reaction, or the compound represented by formula III and di-substituted phosphine oxyhalide are subjected to a double-substitution reaction under alkali to prepare and obtain a compound represented by formula 6 which is then subjected to a reduction reaction to prepare and obtain the compound I;
in which, X is halogen, and R1-R7 in formula 6 are the same as in formula I.
Specifically: a reaction method {circle around (1)} includes the following steps: in tetrahydrofuran, while a reaction temperature is controlled at −78° C. to −20° C., the compound of formula III reacts under alkali for 3-5 hours to remove the X group of formula III, and then reacts with R72PCl or R72PBr at room temperature for 6-12 hours, to obtain the phosphine ligand formula I; or a reaction method {circle around (2)} includes the following steps: in tetrahydrofuran, while the reaction temperature is controlled at −78° C. to −20° C., the compound of formula III reacts under alkali for 3-5 hours to remove the X group of formula III, and then reacts with R72P(O)Cl at room temperature for 6-16 hours to obtain the compound 6, and then using ethylene glycol dimethyl ether or tetrahydrofuran as the reaction solvent, the compound 6 is treated with lithium aluminum hydride and methyl trifluoromethylsulfonate 6, and subjected to a reduction reaction at room temperature for 3-6 hours to obtain the phosphine ligand I, in which a molar ratio of the alkali to the compound represented by formula. III is 2-10:1, a molar ratio of R72PCl or R72PBr to the compound represented by formula III is 2-6:1, a molar ratio of R72P(O)Cl to the compound represented by formula III is 2-6:1, a molar ratio of lithium aluminum hydride to the compound 6 is 340:1, a molar ratio of the methyl trifluoromethansulfonateester to the compound 6 is 1-5:1, and the alkali is tert-butyl lithium, isopropyl magnesium bromide, ethyl magnesium bromide, sec-butyl lithium, or n-butyl lithium.
A synthesis method of compound II is as follows: a racemic or optically active compound represented by formula III, as a raw material, reacts with di-substituted phosphine halide under an effect of an under alkali, and the compound II is prepared through a mono-substitution reaction; or the compound represented by formula III and di-substituted phosphine oxyhalide are subjected to a mono-substitution reaction under an effect of an alkali to prepare a compound represented by formula 7, Which is then subjected to a reduction reaction to prepare and obtain the compound II:
in which, X is halogen, and R1-R7 are the same as in formula II;
Specifically: a reaction method {circle around (1)} includes the following steps: in tetrahydrofuran, while the reaction temperature is controlled at −78° C. to −20° C., the compound III reacts under alkali for 3-5 hours to remove the X group of formula III, and then reacts with R72PCl or R72PBr at room temperature for 6-12 hours, to obtain the phosphine ligand formula II; or a reaction method {circle around (2)} includes the following steps: in tetrahydrofuran, while the reaction temperature is controlled at −78° C. to −20° C., the compound III reacts under alkali for 3-5 hours to remove the X group of formula and then reacts with R72P(O)Cl at room temperature for 6-16 hours to obtain compound 7, and then using ethylene glycol dimethyl ether or tetrahydrofuran as the reaction solvent, the compound 6 is treated with lithium aluminum hydride and methyl trifluoromethanesulfonate and subjected to a reduction reaction at room temperature for 3-6 hours to obtain the phosphine ligand II, in which a molar ratio of the alkali to the compound represented by formula III is 2-10:1, a molar ratio of R72PCl or R72PBr to the compound of formula III is 1-2:1, a molar ratio of R72P(O)Cl to the compound represented by formula III is 1-2:1, a molar ratio of the lithium aluminum hydride to the compound 7 is 3-10:1, a molar ratio of the methyl trifluoromethanesulfonate to the compound 7 is 1-3:1, and the alkali is tert-butyl lithium, isopropyl magnesium bromide, ethyl magnesium bromide, sec-butyl lithium, or n-butyl lithium.
A use of the phosphine ligand is in that the phosphine ligand is complexed with a metal salt of iron, osmium, gold, silver, copper, platinum, rhodium, ruthenium, iridium, nickel, molybdenum, palladium or cobalt to prepare a catalyst.
The phosphine ligand can be independently used as an organic small molecular catalyst for cyclization reaction.
The phosphine ligand can independently used in metal-catalyzed coupling reaction, N-arylamination reaction, and asymmetric reaction, preferably in the metal-catalyzed asymmetric hydrogenation reaction, hydrosilation reaction, hydrogen transfer reaction and asymmetric allylation reaction.
The phosphine ligand of the present application is obtained through a preparation scheme, in which the cheap and easily available 6,6′-dihydroxyl-3,3,3′,3′-tetramethyl-1,1′-spirobiindane is used as a raw material and the compound represented by the formula III serves as the key intermediate. The new phosphine ligand developed in the present application can be used in the catalytic organic reaction, and particularly, serves as a chiral phosphine ligand that is widely used in many asymmetric catalytic reactions including asymmetric hydrogenation reaction and asymmetric allyl alkylation reaction, and thus it has economic practicability and industrial application prospect.
It should be understood that, within the scope of the present application, the above-mentioned various technical features of the present application and various technical features specifically described in the following examples can be combined with one another to constitute new or preferred technical solutions, which will not described in detail for the sake of brevity.
The following examples are provided to facilitating the understanding of the present application, but are not intended to limit to the present application.
General reaction conditions are described as below: when using air-sensitive reagents, all reactions and controls are performed in a nitrogen-filled glove box or using standard Sehlenk technology. The reaction solvents are dried by a general standard process.
100 g of bisphenol A and 500 mL of methanesulfonic acid were added to a reaction flask, stirred and dissolved to obtain a dark red solution. After reaction under stirring at room temperature for 96 hours, the reaction solution was poured into 600 mL of water, cooled and then filtered with suction, and the obtained solid was washed with water. The solid was dissolved with ethanol under reflux, added with 50° C. warm water until no more solid precipitated, and filtered while being warm, and the filter cake was washed with warm water. After drying, 45 g of white flocculent solid, i.e., 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-6,6′-diol (MSPINOL), was obtained, with a yield greater than 99%.
Resolution process of raceme MSPINOL:
23 g of raceme MSPINOL, 26 ml of triethylamine and 0.22 g of 4-(N, N-dimethylamino) pyridine (DMAP) were dissolved in 200 ml of dichloromethane, cooled in an ice bath and added with 32.6 g of L-menthol chloroformate within 30 minutes. Then, the reaction carried out under stirring at room temperature for 6 hours. TLC confirmed that the reaction was sufficient. Next, the reaction solution was washed with dilute hydrochloric acid and brine successively, the organic phase was dried over anhydrous sodium sulfate and filtered, and the filtrate was concentrated and dried to obtain a pair of diastereomer intermediates (RSL-MSPINOL), which was then recrystallized with n-hexane twice to obtain a single diastereomer (RL-MSPNOL) with a yield of 60%; and a retention time of the compound was 23.5 min (HPLC: C18 column, mobile phase, methanol:water=98:2, flow rate 0.8 mL/min, 254 nm). The crystal mother liquor was recrystallized three times with n-hexane to obtain another diastereomer (SL-MSPINOL) with a yield of 30%, and the retention time of this compound was 25 min (HPLC: C18 column, mobile phase methanol:water=98:2, flow rate 0.8 mL/min, 254 nm). In addition, D-menthol chloroformate may be used instead of L-menthol chloroformate in the above process, and the another diastereomer (SL-MSPINOL) may be obtained with a yield of 55%.
1.5 g of compound RL-HMSPINOL was dissolved in 10 ml of methanol, added with 0.66 g of potassium hydroxide, refluxed for 1 hour, concentrated, then added with 20 ml of dichloromethane, and washed successively with dilute hydrochloric acid and saturated brine, the organic phase was dried over sodium sulfate and suction filtered, the filtrate was concentrated and then subjected to flash column chromatography to obtain (R)-MSPINOL with a yield equal to or greater than 98%. Similarly, SL-MSPINOL was quantitatively obtained in the form of (S)-MSPINOL by hydrolysis in the same process as above.
Single crystal data of compound RL-MSPINOL are as follows (
Cell: a=9.6816(3) b=10.6124(4) c=39.6866(13)
alpha=90 beta=90 gamma=90; Temperature: 293 K.
Volume 4077.6(2); Space group P 21 21 21; Hall group P 2ac 2ab
50 g of bisphenol C and 250 mL of methanesulfonic acid were added to a 500 mL round-bottom flask. After reaction while stirring at room temperature for 3 days, 100 mL of methanesulfonic acid was additionally added, and the reaction continued for 1 day to stop the reaction. The reaction solution was poured into a beaker containing 300 mL of crushed ice, and filtered with suction, and the filter cake was washed successively with saturated sodium bicarbonate solution and water. After washing, the obtained crude product was transferred to a 500 mL single-necked flask, an appropriate amount of ethanol was added to just dissolve the product at reflux temperature, water was added until a solid was apparently precipitated, the mixture was fully stirred and cooled to precipitate a large amount of solids, then suction filtered and washed, and the filter cake was dried to obtain 20 g white powdery solid, 3,3,5,3′,3′,5′-hexamethyl-1,1′-spirobiindane-6,6′-diol (HMSPINOL), with a yield of 92%, mp: 250-251° C. 1H NMR (400 MHz, CDCl3): δ=6.92 (s, 2H), 5.85 (s, 2H), 3.95 (s, 2H), 2.30 (d, J=13.0 Hz, 2H), 2.21 (s, 6H), 2.17 (d, J=13.0 Hz, 2H), 1.39 (s, 6H), 1.30 (s, 6H); 13C NMR (100 MHz, CDCl3): δ=153.18, 150.05, 144.54, 123.55, 122.95, 110.50, 59.40, 57.00, 43.12, 31.88, 30.15, 15.97; HRMS (EI-TOF): calcd for C23H28O2 336.2089, found 336.2085.
A resolution process of raceme HMSPINOL:
5 g of raceme HMSPINOL, 9.6 mL of triethylamine and 0.18 g of 4-(N, N-dimethylamino) pyridine (DMAP) were dissolved in 50 mL of dichloromethane, and 7.3 mL of L-menthol chloroformate was added within 30 minutes. Then, the reaction carried out under stirring at room temperature for 3 hours. TLC confirmed that the reaction was sufficient. Next, the reaction solution was washed with dilute hydrochloric acid and brine successively, the organic phase was dried over anhydrous sodium sulfate and filtered, and the filtrate was concentrated to dryness to obtain a pair of diastereomer intermediates (RSL-HMSPINOL), which was then recrystallized with n-hexane. 10 mL of n-hexane was added to the residue of the concentrated solution, dissolved by stirring, then cooled to −20° C. and kept at −20° C. for 12 hours to precipitate a solid, and suction filtered (the filtrate was the crystallization mother liquor, which was collected separately for use), and the obtained solid was washed with cold n-hexane. The above recrystallization process was repeated twice, so that a single diastereomer (SL-HMSPINOL) with a yield of 50% could be obtained; the retention time of the compound was 28.02 min (HPLC: C18 column, 100% Mani mobile phase, flow rate 1.0 mL/min, 254 nm). The above-mentioned separately collected crystallization mother liquor was concentrated to dryness and then added with 13 mL of n-hexane, cooled to −4° C. and crystallized under heat preservation for 48 hours to precipitate a solid, suction filtered and washed with cold n-hexane to obtain another single diastereomer (RL-HMSPINOL) with a yield of 35%; and the retention time of this compound was 24.67 min (HPLC: C18 column, 100% MeOH mobile phase, flow rate 1.0 mL/min, 254 nm).
1.5 g of compound SL-HMSPINOL was dissolved in 20 mL of ethanol, added with 0.66 g of potassium hydroxide, refluxed for 2 hours, concentrated, then added with 20 mL of dichloromethane, and washed successively with dilute hydrochloric acid and saturated brine. The organic phase was dried over sodium sulfate and suction filtered, the filtrate was concentrated and then subjected to flash column chromatography to obtain (S)-HMSPINOL with a yield of 98% or greater. Similarly, RL-HMSPINOL was quantitatively obtained in the form of (R)-HMSPINOL, by hydrolysis in the same process as above.
Single crystal data of compound SL-HMSPINOL are as follows (
Cell: a=10.53555(14) b=16.17984(19) c=24.4076(3);
alpha=90 beta=90 gamma=90; Volume 4160.61(9);
Space group P 21 21 21; Hall group P 2ac 2ab.
NMR spectrum of compound SL-HMSPINOL: 1H NMR (400 MHz, CDCl3) δ 6.99 (s, 2H), 6.55 (s, 2H), 4.55 (td, J=10.9, 4.4 Hz, 2H), 2.32 (d, J=13.1 Hz, 2H), 2.27-2.19 (m, 8H), 2.12 (dd, J=6.8, 5.0 Hz, 2H), 2.01 (dtd, J=13.9, 7.0, 2.6 Hz, 2H), 1.74-1.62 (m, 4H), 1.53-1.23 (m, 17H), 1.15-0.82 (m, 19H), 0.79 (d, J=7.0 Hz, 6H).
Single crystal data of compound RL-HMSPINOL are as follows (
Cell: a=8.02988(12) b=14.0700(2) c=37.5353(6)
alpha=90 beta=90 gamma=90; Temperature: 171 K;
Volume 4240.75(11); Space group P 21 21 21; Hall group P 2ac 2ab.
NMR spectrum of compound RL-HMSPINOL: 1H NMR (400 MHz, CDCl3) δ 6.98 (s, 2H), 6.54 (s, 2H), 4.55 (td, J=10.9, 4.4 Hz, 2H), 2.33 (d, J=13.1 Hz, 2H), 2.22 (m, 8H), 2.10 (d, J=11.9 Hz, 2H), 2.05-1.92 (m, 2H), 1.69 (dd, J=8.9, 6.9 Hz, 4H), 1.54-1.23 (m, 18H), 1.14-0.98 (m, 4H), 0.96-0.85 (m, 14H), 0.79 (d, J=7.0 Hz, 6H).
15.4 g of compound (R)-MSPINOL (molecular weight: 308, 0.05 mol), 15 mL of tert-butanol (0.156 mol), and 180 mL of dichloromethane were added in a reaction flask. After stirring evenly (suspension), 27 mL of methanesulfonic acid (0.41 mol) was added dropwise under ice-water bath cooling, and the turbidity gradually disappeared; after the dropwise addition finished, the reaction liquid became turbid again when the ice-water bath was removed, and the stirring reaction carried out for another 2 hours, and then was quenched by adding 100 mL of ice water. The reaction solution was distilled to remove dichloromethane under reduced pressure, and then at least 200 mL of ethyl acetate was added under stirring to dissolve all precipitated solids; a liquid separation was performed, the aqueous phase was extracted with ethyl acetate, and the organic phases were combined; the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and then was subjected to suction filtering; the filtrate was concentrated to dryness to obtain a white-like solid, which was then purified by rapid ethanol-water recrystallization. The solid was dissolved with an appropriate amount of ethanol at 80° C., until it was just completely dissolved under the reflux state of ethanol, then added with warm water slowly under stirring to precipitate the solid until no more solid precipitated, suction filtered while being still warm, and fully washed with warm water. The filter cake was dried to obtain 20.2 g of white solid compound (R)-BMSPINOL, with a yield of 96%. 1H NMR (400 MHz, CDCl3) δ 7.05 (s, 2H), 5.41 (s, 2H), 3.05 (s, 2H), 2.28 (d, J=13.0 Hz, 2H), 2.10 (d, J=13.0 Hz, 2H), 1.42 (s, 6H), 1.35 (s, 18H), 1.28 (s, 6H).
Under nitrogen atmosphere, 19.6 g of compound (R)-BMSPINOL was dissolved in 200 mL of ethyl acetate, 18.3 g of N-bromosuccinimide (NBS) was added in separated batches, and stirred at room temperature for 16 hours to finish the reaction. 50 mL of saturated sodium bisulfite solution was added to the obtained yellow solution, stirred vigorously for 30 minutes, and separated into different layers. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and then subjected to suction filtering. The filtrate was concentrated to dryness, and then recrystallized with methanol. 50 mL of methanol was added, stirred and refluxed for 5 minutes, followed by fully cooling to room temperature and suction filtering. The filter cake was washed with a small amount of methanol and dried to obtain 25.4 g of light yellow powder, the compound (R)-III-ef with a yield of 90%; NMR (400 MHz, CDCl3) δ 6.98 (s, 2H), 5.80 (s, 2H), 2.49 (d, J=13.1 Hz, 2H), 2.25 (d, J=13.1 Hz, 2H), 1.41 (s, 18H), 1.39 (s, 6H), 1.32 (s, 6H).
15 g of the compound (R)-III-ef was added to a reaction flask and dissolved with 105 mL of toluene. Under cooling in an ice water bath, 2 mL of trifluoromethanesulfonic acid was added, and the reaction was conducted for 1 hour while stirring. The reaction was monitored by TLC until the reaction was complete, and 30 mL of ice water was added to quench the reaction. The reaction solution was evaporated under reduced pressure to remove toluene and extracted with ethyl acetate, and then washed once respectively with saturated brine, saturated sodium bicarbonate solution and saturated brine. The organic phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to remove ethyl acetate; 30 mL of warm n-hexane was added to the concentrate, stirred at reflux for 15 minutes, then cooled to room temperature, and suction filtered. The filter cake was washed with n-hexane and dried to obtain 10.8 g of white powder, compound (R)-III-e, with a yield of 89%. 1H NMR (400 MHz, CDCl3) δ 7.03 (d, J=8.2 Hz, 2H), 6.95 (d, J=8.2 Hz, 2H), 5.47 (s, 2H), 2.52 (d, J=13.1 Hz, 2H), 2.29 (d, J=13.1 Hz, 2H), 1.41 (s, 6H), 1.34 (s, 6H).
Under nitrogen atmosphere, 8.8 g of the compound (R)-III-e, 40 mL of dichloromethane and 3.8 mL of pyridine were added to a reaction flask, stirred to dissolve, and then cooled with an ice water bath; then 6.5 mL of trifluoromethanesulfonic anhydride was slowly added dropwise, and stirred at room temperature to react for 1 hour. The reaction was monitored with TLC until it was complete. The reaction solution was washed successively with dilute hydrochloric acid, saturated sodium bicarbonate solution, and saturated sodium chloride solution. The organic phase was dried over anhydrous sodium sulfate and suction filtered, the filtrate was concentrated to dryness, and then purified by flash silica gel column chromatography to obtain 13.2 g of white solid powder, compound (R)-III-e′, with a yield of 96%. 1H NMR (400 MHz, CDCl3) δ 7.26 (d, J=8.3 Hz, 2H), 7.19 (d, J=8.3 Hz, 2H), 2.59 (d, J=13.3 Hz, 2H), 2.36 (d, J=13.2 Hz, 2H), 1.45 (s, 6H), 1.39 (s, 6H).
Under nitrogen atmosphere, 12 g of the compound (R)-III-e′, 460 mg of bis(triphenylphosphine) palladium dichloride and 351 mg of 1,3-bis(diphenylphosphinopropane) were added to a reaction flask. Then, 170 mL of N, N-dimethylformamide (DMF), 27 mL of triethylamine, and 4.8 mL of formic acid were sequentially injected into the reaction flask while stirring. Then the system reacted under stirring at 80° C. for 80 minutes, and was monitored with TLC until the reaction was complete. After the reaction was cooled to room temperature, 150 mL of water and 50 mL of dilute hydrochloric acid (3M) and 200 mL of ethyl acetate were added to the reaction solution. The liquid was extracted and separated, the aqueous phase was extracted again with ethyl acetate, and the organic phases were combined. The organic phase was washed with saturated saline, and then washed with 5 mL of hydrogen peroxide (30%) with shaking (to oxide the phosphine ligand DPPP therein), and then the organic phase was washed again with saturated saline; the organic phase was dried with anhydrous sodium sulfate, and then concentrated under reduced pressure to obtain a white-like solid. Finally, the white-like solid was purified with the flash column chromatography (200-300 mesh silica gel, E/P=1:20) to obtain 6.8 g of white solid, compound (R)-III-a (with a yield of 95%). 1H NMR (400 MHz, CDCl3) δ 7.29 (dd, J=7.2, 1.2 Hz, 2H), 7.16-7.07 (m, 4H), 2.56 (d, J=13.1 Hz, 2H), 2.27 (d, J=13.1 Hz, 2H), 1.44 (s, 6H), 1.36 (s, 6H).
In a 500 mL three-necked flask, 18 g (R)-HMSPINOL and 200 mL of dichloromethane were added, and 19.8 g of N-bromosuccinimide was added in batches under electromagnetic stirring. The mixture was stirred for 1 hour at room temperature, and TLC (petroleum ether:ethyl acetate=5:1) confirmed that the reaction is finished. A saturated sodium bisulfite solution was added while stirring for 1 hour. The liquid was separated, the aqueous phase was washed with 100 mL of dichloromethane, and the organic phase was combined and washed with saturated brine. The organic phase was dried over anhydrous sodium sulfate and suction filtered. The filtrate was freed from the solvent to obtain 26.4 g of light-yellow solid powder (R)-III-f, with a yield of 99.8%, mp: 228° C. 1H NMR (400 MHz, CDCl3) δ=6.88 (s, 2H), 5.57 (s, 2H), 2.47 (d, J=13.1 Hz, 2H), 2.31 (s, 6H), 2.25 (d, J=13.0 Hz, 2H), 1.39 (s, 6H), 1.33 (s, 6H). 13C NMR (101 MHz, CDCl3) δ=149.25, 145.61, 142.67, 124.51, 123.60, 107.15, 60.85, 55.57, 43.06, 32.58, 29.28, 17.11; HRMS (EI-TOF): calcd for C23H26Br2O2 492.0300, found 492.0302.
Single crystal data are as follows (the structure is shown in
Cell: a=7.5979(5) b=14.0001(10) c=19.6290(12)
alpha=90 beta=90 gamma=90; Temperature: 171 K.
Space group P 21 21 21; Hall group P 2ac 2ab
In a three-necked flask, (R)-III-f (9 g, 18.2 mmol) was added under nitrogen protection, dichloromethane (150 mL) and pyridine (7.7 mL) were then added in sequence, and trifluoromethanesulfonic anhydride (7.7 mL) was added slowly under an ice bath. The reaction was conducted while stirring at room temperature for 1 hour, and monitored by TLC until the reaction was completed. The reaction solution was washed successively with dilute hydrochloric acid, saturated sodium bicarbonate solution, and saturated sodium chloride solution. The organic phase was dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated to dryness, and subjected to flash silica gel column chromatography (eluent:petroleum ether:ethyl acetate 10:1), to obtain a white solid powder (R)-III-f′ (13.2 g, yield: 96%), mp: 206° C. 1H NMR (400 MHz, CDCl3): δ=7.02 (s, 2H), 2.55 (d, J=13.2 Hz, 2H). 2.45 (s, 6H), 2.30 (d, J=13.2 Hz, 2H), 1.42 (s, 6H), 1.36 (s, 6H); 19F NMR (400 MHz, CDCl3): δ=−72.18 (s); 13C NMR (100 MHz, CDCl3); δ=153.74, 145.12, 144.55, 132.61, 124.80, 123.33, 120.14, 116.95, 113.77, 113.37, 61.28, 54.92, 43.43, 32.37, 28.81, 18.16; HRMS (EI-TOF): calcd for C25H24F2Br2O2S2 755.9285, found 755.9285.
In a three-necked flask, (R)-III-f′ (12.9 g), bis(triphenylphosphine) palladium chloride (515 mg), and 1,3-bis (diphenylphosphine propane) (361 mg), under nitrogen protection, were added sequentially with N, N-dimethylformamide (150 mL, DMF) and tripropylamine (38.5 mL), and formic acid (5.1 mL) was added slowly at 0° C. The reaction was conducted under stirring in an oil bath at 80° C. for 1 hour. After the reaction was completed, the solution was cooled to room temperature, and the reaction was quenched with water. Ethyl acetate was added to perform liquid separation extraction. The aqueous phase was extracted with ethyl acetate again. The organic phase was combined, then washed with 30% hydrogen peroxide solution for 5 minutes, then washed successively with 4 mol/L HCl solution, saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over anhydrous sodium sulfate, and subjected to suction filtering. The filtrate was concentrated to dryness, and then subjected to silica gel column flash column chromatography (eluent:petroleum ether:ethyl acetate=50:1) to obtain white powdery solid (R)-III-b, with a yield of 95%, mp: 202° C. NMR (400 MHz, CDCl3): δ=7.18 (s, J=7.4 Hz, 2H), 6.97 (s, 2H), 2.57 (d, J=13.1 Hz, 2H), 2.38 (s, 6H), 2.28 (d, J=13.1 Hz, 2H), 1.43 (s, 6H), 1.38 (s, J=8.2 Hz, 6H); 13C NMR (100 MHz, CDCl3): δ=154.92, 142.48, 138.92, 131.88, 122.32, 119.14, 59.79, 55.36, 43.42, 32.56, 28.94, 20.98.
In a reaction flask, 1.5 g of HMSPINOL, 0.15 g of p-toluenesulfonic acid, and 45 mL of dichloromethane were added, and 2.1 g of N-iodosuccinimide was added slowly under magnetic stirring. The mixture reacted under stirring at room temperature for 6 hours, and TLC (petroleum ether:ethyl acetate=5:1) confirmed the end of the reaction. Excessive saturated sodium disulfite solution was added, and the stirring was continued for 1 hour. The liquid was separated, and the aqueous phase was washed with 20 mL of dichloromethane. The organic phase was combined, washed with saturated brine, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was freed from the solvent to obtain 2.24 g of solid powder III-bg. 1H NMR (400 MHz, CDCl3) δ 7.01 (s, 2H), 5.68 (s, 2H), 2.45 (d, =13.1 Hz, 2H), 2.25 (d, J=13.1 Hz, 2H), 1.42 (s, 6H), 1.41 (s, 18H), 1.33 (s, 6H).
In a reaction flask, 1.5 g of HMSPINOL, 0.195 g of p-toluenesulfonic acid, 45 mL of dichloromethane were added, and 2.254 g of N-iodosuccinimide was added slowly under magnetic stirring. The mixture was stirred at room temperature for 5 hours until TLC (petroleum ether:ethyl acetate=5:1) confirmed the end of the reaction. Excessive saturated sodium bisulfite solution was added, the stirring was continued for 1 hour, and the liquid was separated. The aqueous phase was washed with 20 mL of dichloromethane. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and subjected to suction filtering. The filtrate was freed from the solvent to obtain 2.44 g of yellow solid powder III-h, with a yield of 93%.
In a reaction flask, 3 g of MSPINOL and 3.56 g of potassium carbonate were added, 30 mL of acetone was added, and 1.6 mL of methyl iodide was injected. The reaction solution was warmed up to 35° C., and reacted under stirring for 12 hours until TLC monitored that the raw materials disappeared and completely became a product. 60 mL of concentrated ammonia was added while stirring for 2 hours. After being cooled to room temperature, the solution was suction filtered, washed with warm water 3 times, and dried to obtain 3.04 g of white powder III-j, with a yield of 96%. 1H NMR (400 MHz, CDCl3) δ 7.08 (dd, J=8.2, 4.4 Hz, 2H), 6.82 (dd, J=8.2, 4.4 Hz, 2H), 3.85 (6H), 2.61 (d, J=13.0 Hz, 2H), 2.27 (d, J=13.0 Hz, 2H), 1.42 (s, 6H), 1.35 (s, 6H).
Under nitrogen protection, (R)-III-f′ (0.22 g), phenylboronic acid 0.3 g, potassium bromide 0.1 g, and tetrakis (triphenylphosphine) palladium (50 mg) were added in a reaction flask, and then 2 mL of glycol dimethyl ether (DME), 1 mL of water and 0.45 g of potassium phosphate tribasic trihydrate were added. The solution reacted under stirring at 90° C. for 24 hours. After the reaction was completed, the reaction was quenched with water, extracted with ethyl acetate, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated to dryness and purified with the silica gel column flash column chromatography to obtain a powdery solid (R)-III-ff, with a yield of 55%.
Under nitrogen atmosphere, (R)-III-a (1 g) and 10 mL of anhydrous degassed tetrahydrofuran were added in a flask and cooled to −78° C., and an n-hexane solution of tert-butyllithium (8 mL, 2 mol/L) was added dropwise. The mixture reacted under stirring for 1 hour, then iodine (10 mmol) was added, then the reaction solution was naturally warmed up to room temperature to react overnight, and water was added to quench the reaction. The solution was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated to dryness and purified with the silica gel column flash column chromatography to obtain (R)-III-aa, with a yield of 80%. 1H NMR (400 MHz, CDCl3) δ 7.63 (dd, J=7.7, 0.9 Hz, 2H), 7.19 (dd, J==7.5, 0.9 Hz, 2H), 6.94 (dd, J=14.4, 6.8 Hz, 2H), 2.49 (d, J=13.1 Hz, 2H), 2.27 (d, J=13.0 Hz, 2H), 1.47 (s, 6H), 1.36 (s, 6H).
Under nitrogen atmosphere, (R)-III-b (1 g, 1.08 mmol) and 15 mL of degassed anhydrous tetrahydrofuran were added in a reaction flask, the temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (6 mL, 1.6 M) was added. After three hours of reaction, diphenylphosphine chloride (6 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 6 hours. After the reaction was completed, the reaction was quenched by adding an appropriate amount of dilute hydrochloric acid. The obtained solution was extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with silica gel flash column chromatography (eluent:petroleum ether:ethyl acetate=50:1) to obtain a solid (R)-I-b with a yield of 60%, which is the ligand named (R)-HMSDP); melting point: 269-270° C., [α]D20=96.3° (c 0.12, CH2Cl2); 1H NMR (400 MHz, CDCl3): δ=7.23-7.21 (m, 6H), 7.16 (t, J=7.3 Hz, 2H), 7.05-6.98 (m, 10H), 6.85-6.79 (m, 6H), 2.33 (d, 0.1=13.4 Hz, 2H), 2.29 (s, 6H), 2.14 (d, J=13.4 Hz, 2H), 1.25 (s, 6H), 1.15 (s, 6H); 31P NMR (162 MHz, CDCl3): δ=−20.81 (s); HRMS calcd for C47H46P2 672.3075, found 672.3079.
Under nitrogen atmosphere, (R)-III-b (1 g, 1.08 mmol) and 15 mL of degassed anhydrous tetrahydrofuran were added in a flask, the temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (4 mL, 1.6M) was added. After three hours of reaction, diphenylphosphinyl chloride (6 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 16 hours. After the reaction was completed, the reaction was quenched by adding an appropriate amount of dilute hydrochloric acid. The obtained solution was extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated, and purified with the silica gel flash column chromatography (eluent:petroleum ether:ethyl acetate 2:1) to obtain a white solid hexamethylbis(diphenylphosphinyl) spirobiindane with a yield of 72%. NMR characterization data: 1H NMR (400 MHz, CDCl3): δ=7.57-7.48 (m, 4H), 7.43 (td, J=7.3, 1.3 Hz, 2H), 7.35 (ddd, J=8.3, 5.1, 2.1 Hz, 4H), 7.27 (q, J=7.5 Hz, 6H), 7.12 (s, 2H), 7.07 (td, J=7.9, 2.7 Hz, 4H), 6.81 (d, J=14.1 Hz, 2H), 2.43 (d, J=12.8 Hz, 2H), 2.24 (s, 6H), 2.16 (d, J=12.8 Hz, 2H), 1.37 (s, 6H), 1.27 (s, 6H); 31P NMR (400 MHz, CDCl3): δ=31.22 (s); HRMS (EI-TOF): calcd for C47H46O2P2 704.2973, found 704.2977.
Under nitrogen atmosphere, 1 g of hexamethylbis(diphenylphosphinyl) spirobiindane, 12 mL of glycol dimethyl ether, and 0.1 mL of methyl trifluorornethanesulfonate were added in a reaction flask. After stirring at room temperature for 3 hours, the mixture was cooled to 0° C., and 6.6 mL of tetrahydrofuran solution of lithium aluminium hydride (2.5 mol/L) was added to react at 0° C. for about 3 hours, and TLC confirmed that the reaction was finished. The reaction was quenched with dilute hydrochloric acid. The obtained solution was extracted with ether, and washed sequentially with saturated NaHCO3 solution and saturated NaCl. Then the organic phase was dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with the column chromatography (EA:PE=1:100) to obtain a solid (R)-I-b, with a yield of 90%.
Under nitrogen atmosphere, (R)-III-b (1 g) and 15 mL of degassed anhydrous tetrahydrofuran were added in a reaction flask, the temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (6 mL, 1.6M) was added. After three hours of reaction, diphenyl phosphine chloride (1.2 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 6 hours. After the reaction was completed, the reaction was quenched by adding an appropriate amount of dilute hydrochloric acid. The obtained solution was extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with silica gel flash column chromatography (eluent:petroleum ether:ethyl acetate=50:1) to obtain a solid (R)-II-b, with a yield of 66%, melting point: 197-198° C., [α]D20=5.8° (c 0.06, CH2Cl2). 1H NMR (400 MHz, CDCl3): δ=7.20 (4H), 7.18-7.12 (m, 2H), 7.02 (3H), 6.93-6.87 (m, 3H), 6.78-6.73 (m, 1H), 6.25 (2H), 3.02-2.91 (m, 1H), 2.36 (1H), 2.24 (s, 6H), 2.22 (1H) 2.12 (1H), 1.50 (s, 3H), 1.38 (s, 3H), 1.35 (s, 3H), 1.32 (s, 3H). 31P NMR (162 MHz, CDCl3): δ=622.47 (s). 13C NMR (101 MHz, CDCl3): δ=152.28, 152.20, 151.08, 150.84, 150.76 (d, =2.9 Hz), 148.07 (d, J=4.1 Hz), 138.64 (d, J=14.7 Hz), 135.69 (t, J=6.7 Hz), 135.04 (d, J=2.8 Hz), 134.79, 132.75, 132.54, 131.98, 131.79, 131.57, 131.36, 130.86 (d, J=9.1 Hz), 126.97, 126.91 (d, J=1.7 Hz), 126.53-126.32 (m), 126.13, 122.73 (d, J=4.2 Hz), 121.02, 59.69, 57.24 (d, J=6.9 Hz), 57.07 (d, J=2.7 Hz), 42.56, 41.89, 31.86 (d, J=2.7 Hz), 31.18, 29.16, 27.35 (d, J=2.6 Hz), 20.30 (d, J=11.9 Hz). HRMS (EI-TOF): calcd for C35H37P 488.2633, found 488.2639.
Under nitrogen atmosphere, in a reaction flask, (R)-III-b (1 g, 1.08 mmol) was added and 15 mL of degassed anhydrous tetrahydrofuran was added. The temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (6 mL, 1.6 M) was added. After three hours of reaction, bis(4-trifluoromethylphenyl) phosphine chloride (6 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 6 hours. After completion of the reaction, the reaction was quenched by adding an appropriate amount of dilute hydrochloric acid. The obtained solution was extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with the silica gel flash column chromatography (eluent:petroleum ether:ethyl acetate=50:1) to obtain a solid (R)-I-bg, with a yield of 55%; [α]D20=120.4° (c 0.07, CH2Cl2). 1H NMR (400 MHz, CDCl3): δ=7.47 (d, =7.8 Hz, 4H), 7.22 (d, J=7.7 Hz, 4H), 7.06 (s, 2H), 7.04-6.96 (m, 4H), 6.81 (t, J=7.3 Hz, 6H), 2.34 (m, 8H), 2.32 (s, 2H), 1.29 (s, 6H), 1.23 (s, 6H). 31P NMR (162 MHz, CDCl3): δ=−21.54.
Under nitrogen atmosphere, (R)-III-b (1 g, 1.08 mmol) and 15 mL of degassed anhydrous tetrahydrofuran were added in a reaction flask, and the temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (4 mL, 1.6 M) was added. After three hours of reaction, bis(3,5-di(trifluoromethyl)phenyl) phosphine chloride (6 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 6 hours. After completion of the reaction, the reaction was quenched by adding an appropriate amount of dilute hydrochloric acid. The obtained solution was extracted with ethyl acetate. The organic phase was washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with the silica gel flash column chromatography (eluent:Petroleum ether:ethyl acetate 40:1) to obtain a solid (R)-I-bbg with a yield of 65%.
According to the same reaction process as in Example 13, bis(3,5-di(trifluoromethyl)phenyl)phosphine chloride was replaced with bis(3,4-dimethylphenyl)phosphine chloride, (R)-3,3,5,3′,3′,5′-hexamethyl-7,7′-bis(bis(3,4-dimethylphenyl)phosphino)-1,1′-spirobiindane ((R)-I-bbb) was obtained with a yield of 73%; melting point: 121-122° C., [α]D20=17.9° (c 0.11, CH2Cl2).
According to the same reaction process as in Example 13, bis(3,5-bis(trifluoromethyl)phenyl)phosphine chloride was replaced with (4-methoxyphenyl)phosphine chloride, (R)-3,3,5,3′,3′,5′-hexamethyl-7,7′-bis(bis(4-methoxyphenyl)phosphino)-1,1′-spirobiindane ((R)-I-bbo) was obtained with a yield of 75%.
Under nitrogen atmosphere, (R)-III-a (1 g) and 15 mL of degassed anhydrous tetrahydrofuran were added in a reaction flask. The temperature was reduced to −78° C., and an n-hexane solution of tert-butyllithium (5 mL, 1.6 M) was added. After three hours of reaction, diphenylphosphine chloride (6 mmol) was added. After 30 minutes, the temperature was naturally raised to room temperature, and the reaction continued for 6 hours. After the reaction was completed, dilute hydrochloric acid was added to quench the reaction. The obtained solution was extracted with ethyl acetate, washed with sodium chloride solution, dried over anhydrous sodium sulfate, and suction filtered. The filtrate was concentrated and purified with the silica gel flash column chromatography (eluent:petroleum ether:ethyl acetate=50:1) to obtain a solid (R) I-a with a yield of 72%, which is ligand named (R)-MSDP). 1H NMR (400 MHz, CDCl3) δ 7.27 (t, J=7.5 Hz, 2H), 7.23-7.15 (m, 10H), 7.09-7.01 (m, 6H), 7.00-6.94 (m, 4H), 6.79 (t, J=7.1 Hz, 4H), 2.36 (d, J=13.2 Hz, 2H), 2.19 (d, J=13.2 Hz, 2H), 1.27 (s, 6H), 1.17 (s, 6H). HRMS (EI-TOF) for C45H42P2: 644.2764.
According to the same reaction process as in Example 16, diphenylphosphine chloride was replaced with bis(3,5-bis(trifluoromethyl)phenyl)phosphine chloride, (R)-3,3,3′,3′-tetramethyl-7,7′-bis(bis(3,5-bis(trifluoromethyl)phenyl)phosphino)-1,1′-spirobiindane ((R)-I-af) was obtained with a yield of 60%, ARMS (EI-TOE) for C53H34F24P2: 1188.1755.
According to the same reaction process as in Example 16, diphenylphosphine chloride was replaced with bis(4-(trifluoromethyl)phenyl)phosphine chloride, (R)-3,3,3′,3′-tetramethyl-7,7′-bis(bis(4-(trifluoromethyl)phenyl)phosphino)-1,1′-spirobiindane ((R)-I-aa) was obtained with a yield of 68%, HRMS (EI-TOF) for C49H38F12P2: 916.2257.
Under nitrogen atmosphere, methyl spirophosphine ligand (S)-I-b (the ligand also named (R)-HMSDP, 0.178 mmol) and 2 mL of benzene were added to a reaction flask, and completely dissolved under stirring. Then, 4 ml of benzene solution containing 46 milligrams of bis(acetonitrile) dichloropalladium (0.178 mmol, PdCl2(MeCN)2) was added, and stirred at room temperature for 12 hours to precipitate a solid. Then, the obtained mixture was suction filtered, washed with benzene, and dried under vacuum to obtain a complex PdCl2 ((S)-HMSDP), with a yield of 85%. 1H NMR (400 MHz, CDCl3) δ=7.88-7.69 (m, 4H), 7.29 (m, 4.2 Hz, 6H), 7.14 (m, 4H), 7.03 (m, 2.2 Hz, 4H), 6.62 (s, 2H), 2.13 (s, 6H), 2.09 (d, 12.5 Hz, 2H), 1.64 (d, 12.5 Hz, 2H), 1.17 (s, 6H), 0.52 (s, 6H). 31P NMR (162 MHz, CDCl3) δ 37.65 (s).
In a glove box having nitrogen atmosphere, methyl spirophosphine ligand (R)-HMSDP (0.165 mmol, i.e., compound (R)-I-b) and Ru(C6H6)Cl2 (0.08 mmol, 40 mg) were weighed and added to a Schlenk reaction tube. 3 mL of dry and degassed N, N-dimethylformamide (DMF) was then injected under nitrogen atmosphere, heated to 100° C. under stirring for 2 hours, then cooled to room temperature, and added with (R, R)-1, 2-diphenylethylenediamine ((R, R)-DPEN, 0.165 mmol, 35 mg). The reaction continued under stirring at room temperature for 16 hours. The solvent was removed under vacuum, and after drying, a quantitative solid product RuCl2—[(R)-HMSDP] [(R, R)-DPEN] was obtained.
Under nitrogen atmosphere, 0.4 g of p-tolylboronic acid, 0.2 g of cyclohexenone, 23 mg of palladium acetate, 0.6 g of cesium carbonate, and 83 mg of methyl spiro phosphine ligand (±)-I-b (raceme) were added in a reaction flask, and then 8 ml of toluene and 30 μl of chloroform were injected. The mixture reacted under stirring at 80° C. for 48 hours. The reaction solution was washed with saturated brine. The organic phase was dried over sodium sulfate and then purified with the column chromatography to obtain 330 mg of product 3-(p-tolyl)-cyclohexanone, with a yield of 85%. 1H NMR (400 MHz, CDCl3) δ 7.20 7.03 (m, 4H), 2.98 (m, 1H), 2.57 (m, 1H), 2.52 (m, 1H), 2.49-2.42 (in, 1H), 2.42-2.35 (m, 1H), 2.33 (s, 3H), 2.18-2.10 (m, 1H), 2.06 (m, 1H), 1.89-1.70 (in, 2H).
Under nitrogen atmosphere, 4.8 mg of chiral methyl spiro phosphine ligand (S)-HMSDP and 1 mg of metal [Pd(C3H5)Cl]2) were weighed and added into a Schlenk reaction tube, and 1 mL of toluene was added. The mixture was stirred for 2 hours at room temperature, then cooled to −25° C., and added with 32 mg of 1,3-bis (o-chlorophenyl)-2-allyl acetate. Then, a mixture of dibenzyl malonate (45 μl), Et2Zn (300 μl, 1 M in hexane) and 1 mL of toluene solution, which were previously mixed and stirred for 30 minutes, was added, and the obtained solution was incubated at −25° C. for 2 hours. Then, the reaction was quenched by adding a saturated ammonium chloride solution, and the obtained solution was extracted with ethyl acetate. The organic phase was washed with a saturated sodium chloride solution, dried over anhydrous sodium sulfate to remove the solvent, and then purified with the silica gel column chromatography (ethyl acetate:petroleum ether=1:20)) to obtain a chiral allylated target product, with a yield of 90%, ee=88%; HPLC conditions: Chiralcel IA, iPrOH:Hexane=85:15, flow rate 1.0 mL/min, room temperature, 254 nm, t1: 9.66 min (minor product), t2: 11.88 min (main product). 1H NMR (400 MHz, CDCl3) δ=7.39-7.27 (m, 1H), 7.27-7.20 (m, 10H), 7.20-7.08 (m, 7H), 6.84 (d, J=15.8 Hz, 1H), 6.29 (m, 1H), 5.13 (d, J=1.0 Hz, 2H), 4.98 (q, J=12.3 Hz, 2H), 4.89 (t, J=9.6 Hz, 1H), 4.24 (d, J=10.5 Hz, 1H).
Under nitrogen atmosphere, bis(acetonitrile)dichloropalladium(II) (26 mg, 0.1 mmol) and (R)-MSDP (0.1 mmol) were weighed and mixed in 2 mL of toluene. The mixture reacted under stirring for 2 hours, and was evaporated under reduced pressure to remove the solvent and to be dried. 6 mL of dichloromethane was added, then 3 mL of acetonitrile containing silver trifluoromethanesulfonate (51 mg, 0.2 mmol) was added. The reaction continued under stirring for 5 minutes. The obtained solution was filtered with suction. The filter cake was washed with dichloromethane, the filtrate was concentrated and dried under high vacuum to obtain [(R)-MSDP]Pd(OTf)2 in a quantitative yield. Under nitrogen atmosphere, 0.01 mmol of catalyst [(R)-MSDP]Pd(OTf)2, 0.5 mmol of freshly distilled aniline and 0.75 mmol of 2-naphthyl ethylene were added in a reaction flask, 1 nil, of anhydrous, degassed toluene was injected, and then the reaction was conducted under stirring at 75° C. for 40 hours to end the reaction. Purification was performed with the silica gel column chromatography (ethyl acetate:petroleum ether=1:35) to obtain a target product of asymmetric hydroamination reaction, with a yield of 61%, 41% ee. HPLC conditions: Chiralpak OD-H, n-hexane/EtOH=98/2, flow rate: 0.8 mL/min, room temperature, 254 nm, t1: 20.8 min (main product), t2: 22.8 min (minor product). 1H NMR (400 MHz, CDCl3) δ 7.79 (dd, J=10.9, 5.5 Hz, 4H), 7.53-7.39 (m, 3H), 7.12-7.03 (m, 2H), 6.63 (t, J=7.3 Hz, 1H), 6.59-6.51 (m, 2H), 4.63 (q, J=6.7 Hz, 1H), 4.11 (s, 1H), 1.58 (d, J=6.7 Hz, 3H).
As a comparison, according to the above process, (R)-MSDP was replaced with (R)-SDP, the obtained target product of asymmetric hydroamination reaction had a yield of 10%, 0% ee. That is, the product was raceme.
Under nitrogen atmosphere, 0.05 mmol copper trifluoromethanesulfonate and 0.06 mmol (±)-TMSDP were added in a reaction flask, and 1 mL of 1, 2-dichloroethane was injected. The mixture was stirred at room temperature for 30 minutes, and then 0.5 mmol of 2-(1-styryl) benzoic acid and 1 mmol morpholine benzoate were added to reflux for 1 hour. The reaction solution was added with dichloroethane, washed with saturated sodium bicarbonate, and washed with saturated brine. The organic phase was dried over anhydrous sodium sulfate, then concentrated, and purified by the silica gel column chromatography (ethyl acetate:petroleum ether=1:2) to obtain a target product of a cyclization reaction, with a yield of 81%. 1H NMR (CDCl3, 400 MHz): δ 7.91 (d, J=7.6 Hz, 1H), 7.66-7.49 (m, 5H) 7.41-7.29 (m, 3H), 3.48-3.40 (m, 2H), 3.38-3.29 (m, 2H), 3.21 (d, J=14.2 Hz, 1H), 3.14 (d, J=14.2 Hz, 1H), 2.60-2.50 (m, 2H), 2.27-2.17 (in, 2H).
Under nitrogen atmosphere, (R)-III-b (1 mmol) and 5 mL of ethanol were added in a reaction flask to be dissolved under stirring and refluxing. The solution was then added slowly to 3 mL of ethanol solution in which HAuCl4.4H2O (206 mg, 0.5 mmol) was dissolved, and then reacted under stirring at room temperature for 2 hours, followed by performing suction filtration. The filter cake was dissolved in 5 mL of dichloromethane, and then 50 mL of petroleum ether was added to precipitate a precipitate. Then, the suction filtration was performed, and the filter cake was dried under vacuum to obtain a complex compound of monovalent gold salt, [(R)-III-b]AuCl, with a yield of 80%.
Under nitrogen atmosphere, III-b (0.05 mmol), 0.5 mmol ethyl allenyl formate (In-2) and olefin In-1 were added in a reaction flask, and then 5 mL of toluene was added. The mixture was stirred at room temperature for 12 hours. The reaction solution was concentrated, and then purified silica gel column chromatography to obtain a product In-3 of [3+2] cyclization product, with a yield of 80%.
By performing the above reaction with racemic MSDP instead of III-b, a product In-3 of [3+2] cyclization product can be obtained with a yield of 71%.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201711330428.2 | Dec 2017 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2017/116105 | 12/14/2017 | WO | 00 |
