Synthesis of Allenyl Esters by Horner–Wadsworth–Emmons-Type Reactions of Methyl 2-[Bis(benzylthio)phosphoryl]acetate and Ketenes Using Grignard Reagents

Abstract

Methyl 2-[bis(benzylthio)phosphoryl]acetate and its analogues have proven to be efficient Horner–Wadsworth–Emmons (HWE)-type reagents for synthesizing conjugated allenyl esters and their analogues through reactions with disubstituted ketenes using Grignard reagents. A series of HWE-type reagents containing the bis(benzylthio)phosphoryl group showed better reactivity than the corresponding HWE reagents, where two phosphorus–sulfur bonds were substituted with phosphorus–oxygen bonds.

Keywords

Horner–Wadsworth–Emmons reagents - Phosphorus–sulfur bond - Conjugated allenyl esters - Ketenes - Allenes - Grignard reagents - Olefination

Publication History

Received: 20 May 2025

Accepted after revision: 08 August 2025

Accepted Manuscript online:
11 August 2025

Article published online:
03 September 2025

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