Lipoic acid → alpha Lipoic acid

HRID 1604447Notes

Reaction equation

HRID 1604447 reaction equation
[CH2:1]1[C@@H:5]([CH2:6][CH2:7][CH2:8][CH2:9][C:10]([OH:12])=[O:11])[S:4][S:3][CH2:2]1>C(OC(C)C)(C)C>[CH2:1]1[CH:5]([CH2:6][CH2:7][CH2:8][CH2:9][C:10]([OH:12])=[O:11])[S:4][S:3][CH2:2]1

Participants

3

Reactant 1

HCID 6112Lipoic acid

Product 1

HCID 864alpha Lipoic acidYield 81.3%

Reagents, catalysts & solvents 1

HCID 7914Diisopropyl EtherSolvent

Conditions

Temperature
-7.5 °C

Procedure

A solution which contained 16.6 g R-(+)-thioctic acid and 3.4 g S-(-)-thioctic acid in 80 ml diisopropyl ether was cooled off from 35 to 40° C. down to -5 to -10° C., filtered and dried. 13.5 g thioctic acid were obtained in the novel modification as first crystallizate. The R-(+)thioctic acid content was 78.8% with a melting range of 48 to 54° C.

Workup

  1. filtrationfiltered
  2. customdried

Sources & evidence

ORD record
ord-6d07427f36724b5c94fe858beaab9f9e
Source dataset
uspto-grants-1999_11
Patent number
US05994393

Reaction notes

Loading…