Synthesis Of Enantiopure 2-Malonylvinyl Sulfoxides Via Addition-Elimination Reactions Of 2-Halo- And 2-(Mesyloxy)Vinyl Sulfoxides
Journal Of Organic Chemistry
Enantiomerically pure (E)-2-bromo- and (E)-2-iodovinyl sulfoxides 3a and 3b have been prepared in multigram quantities from (E)-1,2-bis(tri-n-butylstannyl)ethene; enantiomerically pure (E)-2-(mesyloxy) vinyl sulfoxide 3c has been synthesized by reaction of the enolate derived from condensation of 1-lithiomethyl p-tolyl sulfoxide and DMF with methanesulfonyl chloride. These compounds react with anions derived from diethyl alkylmalonates to produce enantiopure 2-malonylvinyl sulfoxides in good to excellent yields and with a high degree of stereoselectivity. The transformations proceed through an ''addition-rotation-elimination'' sequence, and the stereochemical results reinforce the concept that nucleophilic additions to vinyl sulfoxides are sterically controlled and occur predominately syn to the sulfinyl electron lone pair.
J. P. Marino, E. Laborde, C. F. Deering, Robert S. Paley, and M. P. Ventura.
"Synthesis Of Enantiopure 2-Malonylvinyl Sulfoxides Via Addition-Elimination Reactions Of 2-Halo- And 2-(Mesyloxy)Vinyl Sulfoxides".
Journal Of Organic Chemistry.