Synthesis of esters of saturated and unsaturated sixteen-carbon acids deuterated at the terminal or penultimate carbons

✍ Scribed by A.P. Tulloch; L. Bergter

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 438 KB
• Volume: 28
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(81)90020-7

✦ Synopsis

General syntheses of saturated and unsaturated fatty acids, specifically trideuterated at the terminal carbon or dideuterated at the penultimate carbon, from to-hydroxy esters, have been developed. hexadecanoate was synthesized from methyl 16-hydroxyhexadecanoate. The hydroxyl group was protected as the tetrahydropyranyl ether and the ester group reduced with lithium aluminum deuteride, first to an alcohol and then, by way of the derived mesylate, to a trideuteromethyl group. The new ester group was formed by oxidation of the hydroxyl group. Methyl 16-hydroxy[2-2H2]hexadecanoate was prepared, from 16-hydroxyhexadecanoate, by exchange of the a protons and, by the reductive route above, with lithium aluminum hydride, gave methyl [ 15-2H2] hexadecanoate. Methyl 16-hydroxy-7-hexadecynoate was synthesized from 6-chlorohexanol and was converted, by means of the above reactions, to methyl [ 16-=Hs] -and [ 15-2H2] -9-hexadecynoates. Lindlar reduction gave methyl [ 16-2Hs]and [15-2H2] cis-9-hexadecenoates. Overall yields ranged from 30% to 38%.