Alkoxymercuriation of conjugated dienes. Regio- and stereo-selective synthesis of unsaturated diethers

Abstract

The alkoxymercuriation of a series of conjugated dienes with different substitution patterns and mercury(II) salts is described. 1,2-Alkoxymercurials are found to be in equilibria with the corresponding 1,4-regioisomers which are easily solvolysed owing to the allylic character of the C–Hg bond. The use of mercury(II) oxide-tetrafluoroboric acid as the mercuriating agent allows the regio- and stereo-selective (or specific) synthesis of 1,4- and 1,2-diethers.