SYNTHESIS AND EQUILIBRIUM STUDIES OF NEW DIHYDROTHIOPHENE SULFOXIDES

Article abstract of DOI:10.1016/S0040-4020(01)89951-8

Oxidation of the Knoevenagel condensation products 2 of 3-oxo-tetrahydrothiophene (1) and active methylene compounds of the type Z-CH2-COOH with an H2O2/V2O5/t-BuOH reagent furnishes the corresponding sulfoxides 3 in excellent yields.The isomer distributions of the sulfides 2 and the sulfoxides 3 reflect peculiarities of hydrothiophenes as compared to similar open-chain systems and establish that the stabilizing effect of the sulfoxide group on β,γ-double bonds is greater than the corresponding effect of so strongly stabilizing groups as CN and COOR.