Synthesis of Stereotetrads by Regioselective Cleavage of Diastereomeric MEM-Protected 2-Methyl-3,4-epoxy Alcohols with Diethylpropynyl Aluminum

Abstract

The regioselectivity of the epoxide ring opening of 2-methyl-3,4-epoxy alcohols with diethylpropynylalane has been studied as a function of the C1 alcohol protecting group. An efficient selective method was developed using MEM as the protecting group. The reaction proceeded in a highly regioselective manner providing the useful 1,3-diol motif. The undesired 1,4-diol product produced by some free alcohol diastereomers was not observed. This highly stereoselective method provides access to termini-differentiated stereotetrads, which are essential building blocks for polypropionate synthesis.

Key words

cleavage - epoxides - aluminum - stereotetrads - 3,4-epoxy alcohols

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