Preparation of cis-6-hexadecenoic acid, useful in cosmetic and dermatological applications, involves reacting triphenylphosphonium salt with aldehyde in Wittig reaction, and saponifying the resulting ester

摘要

Cis-6-hexadecenoic acid is prepared by reacting a triphenylphosphonium salt with decanal or other aldehyde in a Wittig reaction, and saponifying the resulting ester. Preparation of cis-6-hexadecenoic acid of formula COOH-(CH2)4-CH=CH-(CH2)8-CH3 involves: (a) reacting either: (i) a triphenylphosphonium salt of formula R<1>OOC-(CH2)5-P(R<2>)3<+>X<-> with decanal of formula CH3-(CH2)8-CH=O, or (ii) a triphenylphosphonium salt of formula CH3-(CH2)9-P(R<2>)3<+>X<-> with an aldehyde of formula R<1>OOC-(CH2)4-CH=O in a Wittig reaction; and (b) saponifying the resulting ester of formula R<1>OOC-(CH2)4-CH=CH-(CH2)8-CH3. R<1> = 1-12C alkyl or aryl; R<2> = aryl; X<-> = anion equivalent of (in)organic acid.