Johnson orthoester Claisen rearrangement products of some (1-oxa-4-thiaspiro[4.5]dec-6-en-6-yl)alkanols

Abstract

The crystal structures of two 1-oxa-4-thiaspiro[4.5]decane derivatives, ethyl 6-benzylidene-1-oxa-4-thiaspiro[4.5]decane-7-acetate, C19H24O3S, and (6-ethylidene-1-oxa-4-thiaspiro[4.5]decan-7-yl)ethyl 4-bromobenzoate, C19H23BrO3S, obtained under Johnson orthoester Claisen rearrangement conditions, exhibit different olefin geometry. Both structures are composed of independent molecules separated by normal van der Waals distances. The S-Csp(3) bond distances are significantly different from each other, as has been observed in similar structures; the remaining molecular dimensions are as expected.