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

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.

Key words

reduction - indium(III) bromide - silane - ether

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9

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.