Reductive Deuteration of 4-Benzamido-3-oxo-2-(4-methoxycarbonylbutylidene)tetrahydrothiophene to Give the 3-Deuteroxy Derivative and Its Prototropic Isomerization

Article abstract of DOI:10.1007/BF00505753

The prototropic rearrangement of a deuterated 3-hydroxytetrahydrothiophene with a β,γ-exocyclic double bond is accompanied by deuterium migration along the double bond.Thus 4-r-benzamido-3-t-deuteroxy-3-c-deutero-2-(4-methoxycarbonylbutylidene)tetrahydrothiophene gives cis- and trans-4-r-benzamido-3-oxo-2-(4-methoxycarbonylbutyl)tetrahydro-2,4,4'-d3-thiophene, which, as a result of reduction with sodium borohydride, gives two isomers, viz., 4-r-benzamido-3-t-hydroxy-2-t- and -2-c-(4-methoxycarbonylbutyl)tetrahydrothiophenes that are deuterated in the 2, 4, and 4' positions.