Iridium-Catalyzed Asymmetric Ring-Opening Reactions of Oxabenzonorbornadienes with Amine Nucleophiles
作者:Dingqiao Yang、Yuhua Long、Junfang Zhang、Heping Zeng、Sanyong Wang、Chunrong Li
DOI:10.1021/om100384q
日期:2010.8.23
We have explored a new iridium-catalyzed ring-openingreaction of oxabenzonorbornadienes with a variety of primary aromatic amine or N-substituted piperazine nucleophiles, affording the corresponding products in excellent yields (up to 99%) with moderate enantioselectivity (25−81% ee). The trans configuration of product 2d was confirmed by X-ray crystallography.
A new tunable chiral monophosphine was used as a ligand for asymmetric rhodium-catalyzed ring-opening of oxabenzonorbornadiene with amines, providing a series of chiral ring-opened products in high yields (up to 97%) and with high enantioselectivities (>99%).The reaction can be performed at rt to obtain the desired product with high enantioselectivity. (C) 2014 Elsevier Ltd. All rights reserved.