Synthesis and absolute configuration of (S)-(-)- and (R)-(+)-2, 3-dihydro-2-(1-methylethenyl)-6-methoxybenzofuran

J Nat Prod. 1999 Aug;62(8):1085-7. doi: 10.1021/np980521o.

Abstract

Resolution of racemic 2,3-dihydro-2-carboxy-6-methoxybenzofuran (2) by recrystallizations of diastereomeric salts prepared with (S)-(-)-alpha-methylbenzylamine and (R)-(+)-alpha-methylbenzylamine gave the starting materials for the four-step total syntheses of (S)-(-)-2,3-dihydro-2-(1-methylethenyl)-6-methoxybenzofuran (1a) and (R)-(+)-2,3-dihydro-2-(1-methylethenyl)-6-methoxybenzofuran (1b). Their absolute configuration was established by chemical correlation.