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CC BY-NC-ND 4.0 · Synlett
DOI: 10.1055/a-2347-1027
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Synthesis of Methyl 2-[Bis(benzylthio)phosphoryl]acetate as a Novel Horner–Wadsworth–Emmons-Type Reagent and Its Application to the Diastereodivergent Synthesis of (E)- and (Z)-α,β-Unsaturated Esters

Shigeki Sano∗
,
Shoki Yamada
,
Takahito Ihara
,
Kazumasa Seki
,
Syuji Kitaike
,
Michiyasu Nakao
This work was supported by JSPS KAKENHI grants JP20K06966 and JP23K0602.
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Abstract

Methyl 2-[bis(benzylthio)phosphoryl]acetate has proven to be an efficient Horner–Wadsworth–Emmons (HWE)-type reagent for the diastereodivergent synthesis of (E)- and (Z)-α,β-unsaturated esters. Under the conditions of excess NaHMDS relative to the HWE-type reagent, the HWE-type reactions of methyl 2-[bis(benzylthio)phosphoryl]acetate with various aldehydes afforded the corresponding α,β-unsaturated esters in an E-selective manner in up to 100:0 E/Z ratio. However, when an excess of the HWE-type reagent was used relative to NaHMDS, the stereoselectivity of the HWE-type reactions was dramatically changed from E to Z, yielding an E/Z ratio of up to 2:98.

Key words

Horner–Wadsworth–Emmons reagent - phosphorus–sulfur bond - α,β-unsaturated esters - diastereodivergent synthesis - olefination - aldehydes

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/a-2347-1027.
  • Supporting Information


Publication History

Received: 19 May 2024

Accepted after revision: 14 June 2024

Accepted Manuscript online:
17 June 2024

Article published online:
03 July 2024

© 2024. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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