Enantioselective synthesis of helical molecules: Lipase-catalyzed resolution of bis(hydroxymethyl)[7]thiaheterohelicene

Article abstract of DOI:10.1016/0040-4039(95)00128-Y

Lipase (Pseudomonas cepacia)-catalyzed transesterification of racemic 2, 13-bis(hydroxymethyl)dithieno[3,2-e:3′,2′-e′]benzo[1,2-b:4,3- b′]bis[1]benzothiophene by vinyl acetate in dichloromethane proceeded with a high degree of enantioselectivity to give (P)-(+)-bis(hydroxymethyl)[7]thiaheterohelicene (45% yield, 98% ee), and the corresponding monoacetate (37% yield) and diacetate (13% yield). Reduction of the monoester by LiAlH₄ gave (M)-(-)-bis(hydroxymethyl)[7]thiaheterohelicene with 80% ee and the diester gave the same enantiomer with.