Practical one-pot stereospecific preparation of vicinal and 1,3-diols

A facile one-pot synthesis providing vicinal diols and 1,3-diols in >95% stereoisomeric purity from commercially available enantiopure hydroxy esters has been developed. The esters were reduced with DIBALH and alkylated in situ with 4-pentenylmagnesium bromide, which after workup generated the title diols as diastereomeric pairs. These pairs were easily separated by preparative chromatography, affording products with retained stereoisomeric purity from the starting materials. This method represents an expedient preparation of many common natural products, such as cerambycid beetle pheromones and intermediates towards bicyclic acetal bark beetle pheromones. (C) 2016 Elsevier Ltd. All rights reserved.