SYNTHESIS OF DIALKYL 1,2-EPOXYPHOSPHONATES UNDER PHASE-TRANSFER CATALYST CONDITIONS

Abstract

The reaction of dialkyl phosphonates with chloroacetone and base under phase-transfer catalyst conditions has been investigated. Dialkyl 1,2-epoxyalkylphosphonates are obtained in good yield from the reaction. A two-step mechanism involving deprotonation of the dialkyl phosphonate, followed by nucleophilic attack by the phosphonate anion at the carbonyl group of the ketone is proposed. The oxirane formation during the second stage of the reaction involves displacement of chloride ion. The reaction is highly selective.

Key Words:

• Dialkyl phosphonates
• phase-transfer catalysts
• epoxyphosphonates