Claims
- 1. A process for preparing an aryl-propionic acid of general formula (I) ##STR6## wherein Ar designates an optionally substituted phenyl, naphthyl, or heteroaryl radical, which comprises a single step reaction of catalytically hydrogenating a complex salt of the corresponding 2-hydroxy-2-aryl-propionic acid of formula (II)
- M.sub.m X.sub.x Y.sub.y L.sub.l (II)
- wherein
- M is a bi- or tri-valent metal cation,
- m is 1 or 2
- X is a mono- or di-valent anion of formula (III) ##STR7## wherein Z is --OH or --O, and
- Ar is as defined above, or the corresponding hypercarboxylated form of formula (IV) ##STR8## wherein Ar is defined above
- X is 1, 2, or 3
- Y is a mono- or di-valent organic anion,
- y is 0 or an integer comprised between 1 and 4,
- L is a neutral organic ligand,
- l is 0 or a number between 1 and 4, and the relationship between "m", "x", and "y" are such to provide for salt electroneutrality.
- 2. The process of claim 1 wherein Ar is selected from 4-(2-methyl-propyl)phenyl, 3-phenoxy-phenyl 2-fluoro-biphenylyl, 7-methoxy-10-methyl-2-pheno thiazinyl, and 6-methoxy-2-naphthyl.
- 3. The process of claim 2 wherein Ar is selected from 4-(2-methyl-propyl)phenyl and 6-methoxy-2-naphthyl.
- 4. The process of claim 3 wherein Ar is 6-methoxy-2-naphthyl.
- 5. The process of claim 1 wherein M is selected from Al, Fe, Zn, Mg, and Cu.
- 6. The process of claim 5 wherein M is selected from Al.sup.+3 and Zn.sup.+2.
- 7. The process of claim 1 wherein the catalyst is selected from the group consisting of finely divided, optionally supported, palladium and platinum, rhodium, iridum, platinum, and ruthenium complexes optionally modified with ligands, nickel-Raney and pure nickel.
- 8. The process of claim 7 wherein the catalyst is palladium on carbon.
- 9. The process of claim 1 wherein hydrogen is generated in situ from a "hydrogen donor".
- 10. The process of any of claims 1 to 9 wherein the metal salt which undergoes hydrogenation is obtained via electrochemical carboxylation of the corresponding aryl methyl ketone in a diaphragm-less cell with a dissolving anode.
- 11. A process for the preparation of a 2-aryl-propionic acid of formula (I) ##STR9## wherein Ar designates an optionally substituted phenyl, napthyl, or heteroaryl radical, which comprises submitting to electrochemical carboxylation the corresponding aryl methyl ketone of formula (VI) ##STR10## wherein Ar is as defined above, in a diaphragm-less cell, with a dissolving anode, separating the thus formed metal complex salt and in a single step reaction catalytically hydrogenating said metal complex salt to provide said 2-aryl-propionic acid.
- 12. The process of claim 11 wherein Ar is selected from 4-(2-methyl-propyl)phenyl and 6-methoxy-2-naphthyl.
- 13. The process of claim 12 wherein Ar is 6-methoxy-2-napthyl.
- 14. The process of claim 11 wherein the metal salt is separated from the mixture deriving from the electrocarboxylation by precipitation with one or more precipitating solvents.
- 15. The process of claim 14 wherein the precipitating solvent is an ether.
- 16. The process of claim 15 wherein the precipitating solvent is methyl tert-butyl ether.
- 17. The process of claim 11 wherein the dissolving anodes employed in the electrocarboxylation step are formed from aluminum, zinc, magnesium, copper, iron and their alloys.
Priority Claims (1)
Number |
Date |
Country |
Kind |
20149 A/87 |
Apr 1987 |
ITX |
|
Parent Case Info
This application is a continuation, of application Ser. No. 07/180,580 filed on Apr. 12, 1988, now abandoned.
US Referenced Citations (5)
Number |
Name |
Date |
Kind |
4229367 |
Granwehr et al. |
Oct 1980 |
|
4582577 |
Wagenknecht |
Apr 1986 |
|
4601797 |
Wagenknecht |
Jul 1986 |
|
4708780 |
Silvestri et al. |
Nov 1987 |
|
4814494 |
Shimizu et al. |
Mar 1989 |
|
Non-Patent Literature Citations (1)
Entry |
Rieu et al, "Methods for the Synthesis of Antiinflammatory 2-Aryl Propionic Acids", Tetrahedron, vol. 42, No. 15, (1986), pp. 4095-4131. |
Continuations (1)
|
Number |
Date |
Country |
Parent |
180580 |
Apr 1988 |
|