Novel and Efficient Oxidation of Benzyl Ethers to Benzaldehydes by DMSO/49% Aq. HBr

Abstract

Dimethylsulfoxide (DMSO) oxidizes benzyl ethers into corresponding benzaldehydes at 1108C; the reaction is accelerated by 49% aq. HBr. The conditions work well for different aryl-substituted benzyl ethers. This protocol is inert toward dialkyl ethers.

Nitric‐Acid‐Catalyzed Aerobic Conversion of Benzyl Ethers to Benzaldehydes at Room Temperature

“…[3] By comparison, procedures for the preparation of aryl aldehydes with benzyl ethers are a more challenging goal. In early literatures, such a transformation relies on the use of various oxidants such as H 2 O 2 /Br 2 , [4] t-BuOOH, [5] Ca(ClO) 2 , [6] HOF⋅CH 3 CN, [7] N-bromobutanimide, [8] HNO 3 , [9] DMSO/HBr, [10] H 2 O 2 , [11] NO 2 [12] and so on. Compared with above-mentioned oxidizing agents, the oxygen is a more attractive alternative due to its inexpensive and green characters, [13] which impels chemist to develop various methods with oxygen as the oxidant.…”