Synlett 2019; 30(07): 809-812
DOI: 10.1055/s-0037-1612255
letter
© Georg Thieme Verlag Stuttgart · New York

Direct Synthesis of β,γ-Unsaturated α-Keto Esters from Aldehydes and Pyruvates

John Kamanda Mansaray
,
Jiarui Sun
,
Shisheng Huang
,
Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. of China   Email: orgywj@zstu.edu.cn
› Author Affiliations
We are grateful to the National Natural Science Foundation of China (Grant No. 21702185) and the Science Foundation of Zhejiang Sci-Tech University (Grant No. 16062189-Y).
Further Information

Publication History

Received: 08 December 2018

Accepted after revision: 30 January 2019

Publication Date:
25 February 2019 (online)


Abstract

Herein, we describe two practical methods to synthesize β,γ-unsaturated α-keto esters directly from aldehydes and pyruvates promoted by BF3•Et2O in the presence of Ac2O or by Ti(OEt)4 under mild conditions. A variety of aromatic aldehydes was tolerated to afford the desired products in moderate to excellent yield. Moreover, aliphatic aldehydes and Isatin were also employed to give the γ-alkyl β,γ-unsaturated α-keto esters in moderate yield with use of the Ti(OEt)4 system.

Supporting Information

 
  • References and Notes


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