Easy and stereoselective synthesis of cyclopropyl-substituted phosphonates via α-chlorophosphonates

Abstract

A facile stereoselective synthesis of cyclopropylphosphonates from the reaction of inexpensive α-chlorophosphonates with alkyl acrylates in the presence of sodium hydride is reported. Reaction with dimethyl maleate or fumarate also leads to cyclopropyl-substituted phosphonates. These reactions take place via Michael addition of acrylate, dimethyl maleate, or fumarate to the phosphonate carbanion, followed by expulsion of the chloride ion. © Georg Thieme Verlag Stuttgart.