反应详情

5-Carbomethoxypentanoic acid (12), wherein alk is methyl, was reacted with thionyl chloride and then N-bromosuccinimide (NBS) followed by base hydrolysis to give 2-bromo-5-carbomethoxypentanoic acid (13). Compound (13) was reacted with methyl-3-mercaptopropionate (m=1, R1 '=H and R2 '=OCH3) to yield 5-carbomethoxy-2-[(2-carbomethoxyethyl)thio]-pentanoic acid (14). Compound (14) reacted first with diborane and then with dimethylsulfoxide and trifluoroacetic anhydride to afford 5-carbomethoxy-2-[(2-carbomethoxyethyl)thio]-pentanal (15). Compound (15) was reacted under Wittig conditions with tridecyltriphenylphosphonium ylid to yield methyl-5-[(2-carbomethoxyethyl)thio]-6(Z)-nonadecenoate (16) which was saponified to afford a compound of the formula (IV) wherein m is 1, R1 is hydrogen, and R2 is hydroxyl.