Chemoselective Carbophilic Addition of α-Diazoesters through Ligand-Controlled Gold Catalysis
作者:Yumeng Xi、Yijin Su、Zhaoyuan Yu、Boliang Dong、Edward J. McClain、Yu Lan、Xiaodong Shi
DOI:10.1002/anie.201404946
日期:2014.9.8
α‐aryldiazoesters was achieved through ligand‐controlled gold catalysis. Unlike a dirhodiumcatalyst (which promotes CH insertion and cyclopropanation) and a copper catalyst (which catalyzes OH and NH insertions), the gold catalyst with an electron‐deficient phosphite as the ancillary ligand exclusively gave the carbophilic addition product, thus representing a new and efficient approach to form “carbophilic
Borane-Catalyzed Stereoselective C–H Insertion, Cyclopropanation, and Ring-Opening Reactions
作者:Ayan Dasgupta、Rasool Babaahmadi、Ben Slater、Brian F. Yates、Alireza Ariafard、Rebecca L. Melen
DOI:10.1016/j.chempr.2020.06.035
日期:2020.9
Lewisacidic boranes have been shown to be effective metal-free catalysts for highly selective reactions of donor-acceptor diazo compounds to a range of substrates. The reactions of α-aryl α-diazoesters with nitrogen heterocycles indole or pyrrole selectively generate C3 and C2 C–H insertion products, respectively, in good to excellent yields even when using unprotected indoles. Alternatively, benzofuran
Well‐Defined, Versatile and Recyclable Half‐Sandwich Nickelacarborane Catalyst for Selective Carbene‐Transfer Reactions
作者:Linghua Wang、Saima Perveen、Yizhao Ouyang、Shuai Zhang、Jiao Jiao、Gang He、Yong Nie、Pengfei Li
DOI:10.1002/chem.202005014
日期:2021.3.26
accessible nickel(II)‐based complexes have been rarely used. Herein, an air‐stable nickel(II)‐carborane complex is reported as a well‐defined, versatile and recyclable catalyst for selective carbene transfer reactions with low catalyst loading undermildconditions. This catalyst is effective for several types of reactions including diastereoselective cyclopropanation, epoxidation, selective X−H insertions
Enantioselective Palladium-Catalyzed Carbene Insertion into the N−H Bonds of Aromatic Heterocycles
作者:Vanessa Arredondo、Stanley C. Hiew、Eugene S. Gutman、Ilandari Dewage Udara Anulal Premachandra、David L. Van Vranken
DOI:10.1002/anie.201611845
日期:2017.4.3
C3‐substituted indoles and carbazoles react with α‐aryl‐α‐diazoesters underpalladiumcatalysis to form α‐(N‐indolyl)‐α‐arylesters and α‐(N‐carbazolyl)‐α‐arylesters. The products result from insertion of a palladium‐carbene ligand into the N−H bond of the aromatic N‐heterocycles. Enantioselection was achieved using a chiral bis(oxazoline) ligand, in many cases with high enantioselectivity (up to 99 %
Metal-Free Directed Diastereoselective C2,C3-Cyclopropanation of Substituted Indoles with Diazoesters
作者:Jayanta Ghorai、Pazhamalai Anbarasan
DOI:10.1021/acs.orglett.9b01197
日期:2019.5.3
A metal-free directed C2,C3-cyclopropanation of suitably substitutedindoles with α-diazo esters has been accomplished for the diastereoselective synthesis of cyclopropane-fused indolines in good yield. This method works well with a wide range of differently substituted α-diazo esters as well as indole derivatives and shown excellent compatibility for diverse directing group like pyridyl, pyrimidyl