The (2 + 2) cycloaddition reaction between vinyl alcohol and tetracyanoethylene. A theoretical study of solvent and catalytic effects

Abstract

The cycloaddition reaction between tetracyanoethylene and vinyl alcohol has been studied by means of the MNDO method with CI. Catalytic and solvent effects have been simulated. It has been found that in the gas phase the mechanism is non-concerted with a biradical intermediate. In protic solvents, the intermediate has zwitterionic character and leads to the formation of an acetal.