Chiral P,N-Ligands Based on Ketopinic Acid in the Asymmetric Heck Reaction
作者:Scott R. Gilbertson、Zice Fu
DOI:10.1021/ol006747b
日期:2001.1.1
[figure: see text] Novel chiral P,N-ligands were synthesized from (1S)-(+)-ketopinic acid using palladium-catalyzedcouplingreaction of a vinyl triflate and either a diarylphosphine or a dialkylphosphine as the key step. Palladium complexes of these ligands are efficient catalysts for asymmetric Heck reaction between aryl or alkenyl triflates and cyclic alkenes. Products were obtained with good to
Asymmetric Intermolecular Heck Reaction of Aryl Halides
作者:Chunlin Wu、Jianrong Zhou
DOI:10.1021/ja412277z
日期:2014.1.15
The asymmetric intermolecular Heckreaction has been limited to aryl and vinyl triflates. Herein, we extend the reaction to aryl and vinyl bromides. Various cyclic olefins coupled with high enantioselectivity. Only bisphosphine oxides on a spiro backbone formed highly stereoselective Pd catalysts. The use of alcoholic solvents and alkylammonium salts were essential to promote halide dissociation from
Rational design of cyclopropane-based chiral PHOX ligands for intermolecular asymmetric Heck reaction
作者:Marina Rubina、William M Sherrill、Alexey Yu Barkov、Michael Rubin
DOI:10.3762/bjoc.10.158
日期:——
rigid cyclopropyl backbone was synthesized and tested in the intermolecularasymmetricHeck reaction. Mechanistic modelling and crystallographic studies were used to predict the optimal ligand structure and helped to design a very efficient and highly selective catalytic system. Employment of the optimized ligands in the asymmetricarylation of cyclic olefins allowed for achieving high enantioselectivities
BINAP versus BINAP(O) in Asymmetric Intermolecular Mizoroki-Heck Reactions: Substantial Effects on Selectivities
作者:Thorsten H. Wöste、Martin Oestreich
DOI:10.1002/chem.201101695
日期:2011.10.10
2′‐Bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP) was employed as chiral ligand in the enantioselective intermolecularMizoroki–Heckreaction, whereas the use of cognate BINAP(O) (monooxidized BINAP) is unprecedented. The regio‐ and enantioselectivity of the arylation of representative cyclic alkenes changes dramatically in the presence of hemilabile BINAP(O) instead of BINAP. The arylation of 2,3‐dihydrofuran
Bisphosphine oxides formed highlyactiveasymmetric Heck catalysts, which were applied in asymmetricsynthesis of pharmacologically active azacycles. Olefin insertion proceeded via cis pathways, different from P,N-ligands.