为了证明异氰化物在催化CH键官能化反应中的实用性,开发了2-卤代双芳基与异氰化物的钯催化的环偶联反应。该反应通过在2-卤代联芳基的2'-位上的CH键断裂,提供了一系列芴酮亚胺衍生物。2,6-二取代的苯基异氰化物的使用对于进行该催化环偶联反应至关重要。该反应适用于杂环和乙烯基底物,从而允许构建广泛的环系统。观察到的大的动力学同位素效应(k H / k D = 5.3)表明,CH键的活化是该催化作用中的周转限制步骤。
carbonylation reaction for the synthesis of fluoren‐9‐ones from 2‐halogenated biphenyls using phenyl formate as a carbon monoxide surrogate was achieved. The combined use of cesium carbonate and o‐anisic acid resulted in a remarkable rate enhancement, where the reaction was complete within 3 min in some cases. Mechanistic studies indicated that the turnover‐limiting step of the reaction was the C−H bond‐cleaving
Ligands for metals and improved metal-catalyzed processes based thereon
申请人:Massachusetts Institute of Technology
公开号:US06307087B1
公开(公告)日:2001-10-23
One aspect of the present invention relates to novel ligands for transition metals. A second aspect of the present invention relates to the use of catalysts comprising these ligands in transition metal-catalyzed carbon-heteroatom and carbon-carbon bond-forming reactions. The subject methods provide improvements in many features of the transition metal-catalyzed reactions, including the range of suitable substrates, reaction conditions, and efficiency.
Mild, visible light-mediated decarboxylation of aryl carboxylic acids to access aryl radicals
作者:L. Candish、M. Freitag、T. Gensch、F. Glorius
DOI:10.1039/c6sc05533h
日期:——
Herein we present the first example of aryl radical formation via the visible light-mediated decarboxylation of aryl carboxylic acids using photoredox catalysis.
在本文中,我们介绍了使用光氧化还原催化作用通过可见光介导的芳基羧酸脱羧形成芳基的第一个例子。
CATALYST FOR ASYMMETRIC HYDROGENATION
申请人:MAEDA Hironori
公开号:US20100324338A1
公开(公告)日:2010-12-23
This invention aims at providing a catalyst for producing an optically active aldehyde or an optically active ketone, which is an optically active carbonyl compound, by carrying out selective asymmetric hydrogenation of an α,β-unsaturated carbonyl compound, particularly a catalyst which is insoluble in a reaction mixture for obtaining optically active citronellal which is useful as a flavor or fragrance, by carrying out selective asymmetric hydrogenation of citral, geranial or neral; and a method for producing a corresponding optically active carbonyl compound. The invention relates to a catalyst for asymmetric hydrogenation of an α,β-unsaturated carbonyl compound, which comprises a powder of at least one metal selected from metals belonging to Group 8 to Group 10 of the Periodic Table, or a metal-supported substance in which at least one metal selected from metals belonging to Group 8 to Group 10 of the Periodic Table is supported on a support, an optically active cyclic nitrogen-containing compound and an acid.