Formation of Deoxybenzoins from 1,3-Dimethyl-2-(.ALPHA.-benzyloxybenzyl)benzimidazolium Iodides through Rearrangement Followed by Expulsion of Azolium Ylide.
Treatment of several 1, 3-dimethyl-2-(α-benzyloxybenzyl)benzimidazolium iodides 1 with K2CO3 gave deoxybenzoins 2 in moderate yields. Deoxybenzoins 2 were produced through rearrangement of benzyl groups followed by expulsion of 1, 3-dimethylbenzimidazolium ylide (4). The reaction is classified as a Witting rearrangement.
Structures and Reactivities of O-Methylated Breslow Intermediates
作者:Biplab Maji、Herbert Mayr
DOI:10.1002/anie.201204524
日期:2012.10.8
As close as you can get: Since Breslowintermediates usually exist in their keto form, their O‐protected tautomers may be considered as their closest isolable relatives. A series of these compounds have been synthesized, their structures determined, and the kinetics of their reactions with electrophiles investigated.