Highly Diastereo‐ and Enantioselective Synthesis of Nitrile‐Substituted Cyclopropanes by Myoglobin‐Mediated Carbene Transfer Catalysis
作者:Ajay L. Chandgude、Rudi Fasan
DOI:10.1002/anie.201810059
日期:2018.11.26
chemobiocatalytic strategy for the highly stereoselective synthesis of nitrile‐substituted cyclopropanes is reported. The present approach relies on an asymmetric olefin cyclopropanation reaction catalyzed by an engineered myoglobin in the presence of ex situ generated diazoacetonitrile within a compartmentalized reaction system. This method enabled the efficient transformation of a broad range of olefin substrates
A transition-metal-free & diazo-free styrene cyclopropanation
作者:Ana G. Herraiz、Marcos G. Suero
DOI:10.1039/c9sc02749a
日期:——
An operationally simple and broadly applicable novel cyclopropanation of styrenes using gem-diiodomethyl carbonyl reagents has been developed. Visible-light triggered the photoinduced generation of iodomethyl carbonyl radicals, able to cyclopropanate a wide array of styrenes with excellent chemoselectivity and functional group tolerance. To highlight the utility of our photocyclopropanation, we demonstrated
Gold-Catalyzed Deoxygenative Nazarov Cyclization of 2,4-Dien-1-als for Stereoselective Synthesis of Highly Substituted Cyclopentenes
作者:Chung-Chang Lin、Tse-Min Teng、Chung-Chih Tsai、Hsin-Yi Liao、Rai-Shung Liu
DOI:10.1021/ja806415t
日期:2008.12.3
annulation products reveals evidence for the participation of Nazarov cyclization. This deoxygenative cyclization is extensible to a tandemintramolecularcyclization/nucleophilic addition cascade, giving polycyclic carbo- or oxacyclic compounds with controlled stereochemistry. This new gold catalysis is applied to a short synthesis of natural compounds of the brazilane family, including brazilane, O-trimethyl-
Ni-Catalyzed Reductive Allylation of α-Chloroboronates to Access Homoallylic Boronates
作者:Yixian Lou、Jian Qiu、Kai Yang、Feng Zhang、Chenglan Wang、Qiuling Song
DOI:10.1021/acs.orglett.1c01213
日期:2021.6.18
transition-metal-catalyzed allylation reaction is an efficient strategy for the construction of new carbon–carbon bonds alongside allyl or homoallylic functionalization. Herein we describe a Ni-catalyzed reductive allylation of α-chloroboronates to efficiently render the corresponding homoallylic boronates, which could be readily converted into valuable homoallylic alcohols or amines or 1,4-diboronates
过渡金属催化的烯丙基化反应是在烯丙基或均烯丙基官能化的同时构建新碳-碳键的有效策略。在本文中,我们描述了 α-氯硼酸酯的 Ni 催化还原烯丙基化,以有效地生成相应的高烯丙基硼酸酯,其可以很容易地转化为有价值的高烯丙基醇或胺或 1,4-二硼酸酯。该反应具有广泛的底物范围和良好的官能团兼容性,是对现有制备高烯丙基硼酸酯方法的补充。
Diiodomethane-Mediated Generation of <i>N</i>-Aryliminium Ions and Subsequent [4 + 2] Cycloadditions with Olefins
作者:Yu-Quan Zhao、Jun-Jie Tian、Chong-Ren Ai、Xiao-Chen Wang
DOI:10.1021/acs.joc.9b03148
日期:2020.2.21
between N,N-dimethylanilines, diiodomethane, and olefins. This transformation involves initial reaction of the aniline with diiodomethane to form an iodomethylammonium salt, which undergoes fragmentation accompanied by elimination of methyl iodide to give an N-aryliminium ion, which is trapped by the olefin via [4 + 2] cycloaddition to give the final product. This method for generating N-aryliminium ions