Process for the preparation of lipoic acid and dihydrolipoic...

Details Process for the preparation of lipoic acid and dihydrolipoic... Process for the preparation of lipoic acid and dihydrolipoic...

2006-09-19

2006-09-19

Keys, Rosalynd (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Fatty compounds having an acid moiety which contains the...

C514S440000, C514S557000, C424S401000, C549S039000, C562S512000, C252S183110, C252S183130

Reexamination Certificate

active

07109362

ABSTRACT:
The present invention relates to a process for the preparation of R- and S-lipoic acid and R- and S-dihydrolipoic acid comprising(a) reaction ofwhereMS is SO2—R′ and R and R′ independently of one another are C1–C6-alkyl, C3–C8-cycloalkyl, C3–C8-cycloalkylalkyl, aryl or aralkyl, with sodium sulfide and sulfur in methanol. The invention especially relates to processes for preparing pure R- or S-dihydrolipoic acid, which is either used directly or processed further to give R- and S-lipoic acid. The process also serves for the production of pharmaceuticals. The present invention further relates to a solution of sodium sulfide trihydrate and sulfur in methanol, the sulfur being present in a molar excess over the sodium sulfide trihydrate, and a kit which comprises the solution according to the invention.

REFERENCES:
patent: 5530143 (1996-06-01), Balkenhohl et al.
patent: 5693664 (1997-12-01), Wessel et al.
patent: 5728735 (1998-03-01), Ulrich et al.
patent: 6441024 (2002-08-01), Klatt et al.
patent: 6906210 (2005-06-01), Klatt et al.
patent: 41 36 773 (1993-05-01), None
patent: 43 43 592 (1995-06-01), None
patent: 43 43 593 (1995-06-01), None
patent: 0487 986 (1992-06-01), None
patent: 487 986 (1992-06-01), None
patent: 543 088 (1993-05-01), None
patent: 487 986 (1995-06-01), None
patent: 812 590 (1997-12-01), None
patent: 00/08012 (2000-02-01), None
patent: 00/24734 (2000-05-01), None
patent: 00/53601 (2000-09-01), None
patent: 00/59899 (2000-10-01), None
Rao et al, Synthetic Communications, 17(11) pp. 1339-1347 (1987).
XP-001063331, Bringmann et al.
Short and Productive Syntheses..Bringmann etal.655-661.
Bio.MedChem,vol. 5 No. 2,253-261,1997, Adger et al.
J.Sci.Ind.Res.,vol. 49,8/90, 440-409, Yadav et al.
Tet.Ltrs.,vol. 30,No. 42,5705-5708,1989, Gopalan et al.
JP 8814/64 Abst. 1960-24703.
Synthetic Comm.,17(11) ,1339-1347(1987) Rao et al.
J.Chem.Soc.Perkin Trans,1988,9-12,1988, Brookes et al.
TetrahydronLett,28 1987, 19, 2183-2186,Rao et al.
Chem.Comm. 1983, 1051-1053, Brookes et al.

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