Stereospecificity of the Au(I)-catalyzed reaction of 1-alkynyl-bicyclo[4.1.0]-heptan-2-ones with nucleophiles
摘要:
The stereospecificity of the Au(I)-catalyzed reaction of 1-alkynyl-bicyclo[4.1.0]-heptan-2-ones with nucleophiles was investigated. The substrates were prepared in non-racemic form (up to 88% ee) through parallel kinetic resolution (CBS reduction) and reoxidation of the separated diastereomeric alcohols. The key Au-catalyzed reaction was then found to proceed without significant loss of absolute stereochemical information: this way, an achiral carbocationic intermediate could be excluded. Thus, a bicyclobutonium-type intermediate seems to be attacked in a S(N)2-type fashion by the nucleophile in accordance with computational predictions. (C) 2010 Elsevier Ltd. All rights reserved.
Gold-Catalyzed Cascade Cyclization and 1,3-Difunctionalization To Access Polysubstituted Furans
作者:Yong Xu、Jiangtao Sun
DOI:10.1021/acs.orglett.0c04090
日期:2021.2.5
Gold-catalyzedcascadecyclization and 1,3-difunctionalization of 2-(1-alkyny)-2-alken-1-ones with N,O-acetals are described, leading to the discovery of novel 1,3-oxyaminomethylation and 1,3-aminomethylamination. Typically, by varying the reaction conditions especially the gold catalysts, these two distinct reaction pathways can be controlled in a selective manner. Moreover, tandem cyclization and
Highly Efficient Synthesis of Multisubstituted Furans through Cupric Halide-Mediated Intramolecular Halocyclization of 1-(1-Alkynyl)cyclopropyl Ketones
作者:Mei Zhu、Wei-Jun Fu、Chen Xu、Guang-Long Zou、Zhi-Qiang Wang、Bao-Ming Ji
DOI:10.1002/ejoc.201200601
日期:2012.8
A convenient and efficient method for the synthesis of 3-halofurans was developed by using a cascade reaction between 1-(1-alkynyl)cyclopropyl ketones and cupric halide. Under mild reaction conditions, both 3-chloro- and 3-bromofuran derivatives were obtained in high yields. The reaction involves consecutive multiple bond formations, includingC–O and C–Br bonds, with high regioselectivity. Mechanistic
Synthesis of Polysubstituted Pyrroles through the Tandem 1,3-Addition/5-<i>endo</i>-<i>dig</i>Cyclization of 1-(1-Alkynyl)cyclopropyl Imines
作者:Aurelija Urbanaitė、Inga Čikotienė
DOI:10.1002/ejoc.201600985
日期:2016.11
Cyclopropyl-tethered 3-alkynyl imines react with polarized-covalent-bond-containing compounds to give polyfunctionalized pyrroles. This provides a mild and effective method for the simultaneous introduction of halogen, chalcogen, or hydrogen groups to the 3-position of the pyrrole ring, together with the incorporation of halogen, azide, or alkoxy/aryloxy groups into the ethyl side-chain.
Gold(I)-Catalyzed Reaction of 1-(1-Alkynyl)-cyclopropyl Ketones with Nucleophiles: A Modular Entry to Highly Substituted Furans
作者:Junliang Zhang、Hans-Günther Schmalz
DOI:10.1002/anie.200601252
日期:2006.10.13
Highly Substituted Pyrroles by a Gold(I)-Catalyzed Tandem Reaction of 1-(1-Alkynyl)cyclopropyl Oxime Ethers with Nucleophiles
作者:Junliang Zhang、Yanqing Zhang
DOI:10.1055/s-0031-1290978
日期:2012.6
A gold(I)-catalyzed tandem reaction of 1-(1-alkynyl) cyclopropyl oxime ethers with nucleophiles under mild conditions has been developed, which provides a facile access to highly substituted pyrroles in moderate to excellent yields.