Synthesis 2008(21): 3533-3536  
DOI: 10.1055/s-0028-1083191
PSP
© Georg Thieme Verlag Stuttgart ˙ New York

Direct Reduction of Esters to Ethers with an Indium(III) Bromide/Triethylsilane Catalytic System

Norio Sakai*, Toshimitsu Moriya, Kohji Fujii, Takeo Konakahara
Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science (RIKADAI), Noda, Chiba 278-8510, Japan
e-Mail: [email protected];
Further Information

Publication History

Received 27 June 2008
Publication Date:
16 October 2008 (online)

Abstract

An indium(III) bromide-triethylsilane reagent system promotes direct reduction of esters to produce the corresponding unsymmetrical ethers. This simple catalytic system accommodated other carbonyl compounds, such as a tertiary amide and a carboxylic acid.

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When the reaction was carried out using 2 and 3 equiv of Et3SiH, the product 2a was obtained in 67% and 91% yields, respectively. Using more than 3 equiv of Et3SiH led to complete reduction.