Al Lewis acid-catalyzed regiodivergent 1,2-rearrangement of α-siloxy aldehydes: scope and mechanism
摘要:
Regiodivergent 1,2-rearrangement of alpha-siloxy aldehydes bearing alpha-aryl and alpha-alkyl substituents into alpha-siloxy ketones has been realized by using different Al Lewis acid catalyst/solvent systems. The scope of this unprecedented protocol has been investigated with various substrates, clearly demonstrating its utility for the selective synthesis of two structural isomers from one substrate. Controlled experiments proved that the regiodivergency resulted from the switch of the migrating group. (C) 2009 Elsevier Ltd. All rights reserved.
Enantioselective Acyloin Rearrangement of Acyclic Aldehydes Catalyzed by Chiral Oxazaborolidinium Ion
作者:Soo Min Cho、Si Yeon Lee、Do Hyun Ryu
DOI:10.1021/acs.orglett.1c00314
日期:2021.2.19
A catalytic enantioselective acyloin rearrangement of acyclic aldehydes to synthesize highly optically active acyloin derivatives is described. In the presence of a chiral oxazaborolidinium ion catalyst, the reaction provided chiral α-hydroxy aryl ketones in high yield (up to 95%) and enantioselectivity (up to 98% ee). In addition, the enantioselective acyloin rearrangement of α,α-dialkyl-α-siloxy