PURPOSE: 2-Alkylthiopropionic derivative or ester is subjected to selectively reductive desulfurization to produce titled compound having antiinflammatory, analgesic and antipyretic activities through a shortened process.
CONSTITUTION: The use of a nickel-aluminum alloy permits the selectively reductive desulfurization of 2-alkylthiopropionic derivative or ester of formula I (Ar is aromatic group; Y is -CH=CH-, S; R1 is lower alkyl, aryl; R2 is H, lower alkyl) and propionic derivative or ester of formula II is obtained, such as 2-(3-benzoyl- phenyl)propionic acid (Ketoprofen). This catalyst can selectively eliminate only alkyl group safely in high yield. The starting material of formula I is obtained by leading an aromatic aldehyde of formula VI to a compound of formula IX and methylating the compound with a methylating agent in the presence of a base.
HASHIMA ISAO
ARAI KAZUTAKA
SAKOTA RIYOUZOU
TAKAKUWA YASUO
DOBASHI GENICHI
OGURA KATSUYUKI
SAGAMI CHEM RES