Patent ID: 7057058
Filing Date: 2006-06-06
Classification: C07B,C07C

Abstract:
1. A process for the preparation of 13-cis-retinoic acid (I) comprising: a) reacting 3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4-pentadienyl)-triphenylphosphonium chloride (IIa) with 5-hydroxy-4-methyl-2(5H)-furanone (III) b) isomerising the product of step a) in an organic solvent and in the presence of Pd(II) complex characterised in that step a) is carried out in ethanol as the solvent and KOH as the base, at a temperature ranging from −5 to 0° C.