A copper(II)-catalyzed, sequential Michael–aldol reaction for the preparation of 1,2-dihydroquinolines
作者:Anna M. Wagner、Claire E. Knezevic、Jessica L. Wall、Victoria L. Sun、Joshua A. Buss、LeeAnn T. Allen、Anna G. Wenzel
DOI:10.1016/j.tetlet.2011.12.017
日期:2012.2
A copper(II)-catalyzed, sequential Michael addition-aldol condensation reaction of N-carboxybenzyl-protected aminobenzaldehyde with various α,β-unsaturated N-acyl pyrroles is described. Substrate scope was found to include both aryl and aliphatic N-acyl pyrroles as the Michael acceptors, and isolated product yields as high as 93% were observed. The use of acetonitrile as the reaction solvent proved
Azetidine-derived dinuclear zinc catalyzed asymmetric phospha-Michael addition of dialkyl phosphite to α,β-unsaturated carbonyl compounds
作者:Shanshan Liu、Na Shao、Feng-Zhen Li、Xiao-Chao Yang、Min-Can Wang
DOI:10.1039/c7ob02222k
日期:——
The asymmetric phospha-Michael addition of dialkyl phosphite to α,β-unsaturated carbonyl compounds by using an azetidine-derived dinuclear zinc catalyst was described. The catalyst was proved to be general and efficient for a broad spectrum of enones and α,β-unsaturated N-acylpyrroles. A series of phosphonate-containing compounds were generated with excellent enantioselectivities (up to 99% ee) and
Highly Enantioselective Conjugate Additions of Phosphites to α,β-Unsaturated<i>N</i>-Acylpyrroles and Imines: A Practical Approach to Enantiomerically Enriched Amino Phosphonates
作者:Depeng Zhao、Yuan Wang、Lijuan Mao、Rui Wang
DOI:10.1002/chem.200901901
日期:2009.10.19
The first highlyenantioselective phosphonylation of α,β‐unsaturated N‐acylpyrroles has been developed. Excellent yields (91–99 %) and enantioselectivities (up to >99 % enantiomeric excess (ee)) were observed for a broad spectrum of both phosphites and N‐acylpyrroles under mild conditions. In particular, when diethyl phosphite was employed to test the scope of the N‐acylpyrroles, almost optically pure
Copper(I)-catalyzed enantioselective borylation of alpha,beta-unsaturated N-acylindoles as well as N-acylpyrroles was efficiently achieved by means of bis(pinacolato)diboron (B(2)pin(2)), affording the enantioenriched products in excellent yields with up to 99% ee. The present work provides an alternative class of Michael acceptors, that is, alpha,beta-unsaturated N-acylindoles, for potential asymmetric transformations.
Catalytic Asymmetric Hydrophosphinylation of α,β-Unsaturated <i>N</i>-Acylpyrroles: Application of Dialkyl Phosphine Oxides in Enantioselective Synthesis of Chiral Phosphine Oxides or Phosphines
作者:Depeng Zhao、Lijuan Mao、Yuan Wang、Dongxu Yang、Quanliang Zhang、Rui Wang
DOI:10.1021/ol100504h
日期:2010.4.16
Dialkyl phosphine oxides were introduced in catalytic asymmetric transformations for the first time. An unprecedented phospha-Michael reaction of dialkyl phosphine oxide with alpha,beta-unsaturated N-acylpyrroles was disclosed. Excellent enantioselectivities (94-99% ee) and chemical yields (up to 99%) were achieved with a broad substrate scope of the N-acylpyrroles. Importantly, pyridine was found to be critical to achieve good results for the present reaction.