C-1 Reactivity of 2,3-Epoxy Alcohols via Oxirane Opening with Metal Halides: Application and Synthesis of Naturally Occuring 2,3-Octanediol, Muricatacin, 3-Octanol, and 4-Dodecanolide

Article abstract of DOI:10.1021/jo00120a025

The C-1 reactivity of 2,3-epoxy alcohols and derivatives has been examined thoroughly.In the first approach a rearrangement opening of 2,3-epoxy alcohols with LiI leads to 1-iodo 2,3-diols with erythro or threo stereochemistry starting from trans or cis epoxy alcohols.Subsequent coupling with a carbon nucleophile can lead to a series of vicinal diols with predicted relative and absolute stereochemistry: the described methodology has been applied to the asymmetric synthesis of the naturally occuring (S,S)-2,3-octanediol and (R,R)-muricatacin.The second approach, starting from easily available tosyloxy epoxides, leads to the highly regioselective opening of the oxirane ring with Li halides.The 3-iodohydrins obtained can be reduced to the corresponding 1-(tosyloxy)alkan-2-ols and then coupled with common carbon nucleophiles to afford, in high yields, optically active alcohols.This methodology has been applied to the asymmetric synthesis of naturally occuring pheromones like 3(R)-octanol and 4(R)-dodecanolide.