An unexpected reaction of diethyl phosphite with electron-deficient dialkyl dicyanofumarates

GRAPHICAL ABSTRACT

Abstract

Diethyl phosphite reacts with both dimethyl dicyanofumarate and dicyanomaleate in boiling 1,2-dichloroethane to yield, after chromatographic workup, a 1:1-mixture of the corresponding meso- and dl-dicyanosuccinates. The analogous transformation was observed in the cases of diethyl and diisopropyl dicyanofumarates. A reaction pathway via initial formation of a P–C bond followed by its hydrolytic cleavage is proposed.

Keywords:

• Addition reactions
• reaction mechanisms
• electron deficient alkenes
• dialkyl phosphites
• Michael addition