Electron-Deficient Olefin Ligands Enable Generation of Quaternary Carbons by Ni-Catalyzed Cross-Coupling
作者:Chung-Yang (Dennis) Huang、Abigail G. Doyle
DOI:10.1021/jacs.5b02503
日期:2015.5.6
A Ni-catalyzed Negishi cross-coupling with 1,1-disubstituted styrenyl aziridines has been developed. This method delivers valuable β-substituted phenethylamines via a challenging reductive elimination that affords a quaternary carbon. A novel electron-deficient olefin ligand, Fro-DO, proved crucial for achieving high rates and chemoselectivity for C-C bond formation over β-H elimination. This ligand
Visible-Light-Induced Meerwein Fluoroarylation of Styrenes
作者:Hai-Jun Tang、Bin Zhang、Fei Xue、Chao Feng
DOI:10.1021/acs.orglett.1c01249
日期:2021.5.21
An unprecedented approach for assembling a broad range of 1,2-diarylethane derivatives with fluorine-containing fully substituted carbon centers was developed. The protocol features straightforward operation, proceeds under metal-free condition, and accommodates a large variety of synthetically useful functionalities. The critical aspect to the success of this novel transformation lies in using aryldiazonium
Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile
作者:Katharina J. Hock、Robin Spitzner、Rene M. Koenigs
DOI:10.1039/c7gc00602k
日期:——
Diazo acetonitrile has long been neglected despite its high value in organicsynthesis due to a high risk of explosions. Herein, we report our efforts towards the transient and safe generation of this diazo compound, its applications in iron catalyzed cyclopropanation and cyclopropenation reactions and the gram-scale synthesis of cyclopropyl nitriles.
Asymmetric Calcium Catalysis: Highly Enantioselective Carbonyl-Ene and Friedel-Crafts Reactions for the Synthesis of Quaternary α-Hydroxy Esters Bearing a Trifluoromethyl Group
Enantioselectivecalcium‐catalyzed addition reactions of styrene and indole derivatives with trifluoropyruvates have been developed. The alkaline‐earth metal‐catalyzed reactions proceed smoothly to afford the corresponding products in high yields and with good to excellent enantioselectivities under mild reaction conditions.
Metal-Catalyzed Cycloisomerization of Enyne Functionalities via a 1,3-Alkylidene Migration
作者:Ming-Yuan Lin、Arindam Das、Rai-Shung Liu
DOI:10.1021/ja062515h
日期:2006.7.1
We report a new metal-catalyzed 6-endo-dig cyclization of cis-4,6-dien-1-yn-3-ols, which produces substituted benzene and naphthalene derivatives with structural reorganization. In this process, we observe a 1,3-alkylidene migration via cleavage of the olefin double bond of the starting substrates. The ease and reliability of this cyclization are manifested by its compatibility with a wide array of diverse substrates and several pi-alkyne activators, including PtCl2, Zn(OTf)2, AuCl, and AuCl3.