N-Heterocyclic carbene-palladacyclic complexes: synthesis, characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides
作者:Feng Liu、Yuan-Yuan Hu、Di Li、Quan Zhou、Jian-Mei Lu
DOI:10.1016/j.tet.2018.07.052
日期:2018.9
a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very lowcatalystloadings (0.01 mol%).
METHODS OF PREPARING a,ß-UNSATURATED OR a-HALO KETONES AND ALDEHYDES
申请人:International Flavors & Fragrances Inc.
公开号:US20170174607A1
公开(公告)日:2017-06-22
Copper(II) bromide mediated oxidation of acylated enol and use of the reaction in the synthesis of α,β-unsaturated or α-bromo ketones or aldehydes are disclosed. The method provides an efficient and practical process for manufacturing dehydrohedione (DHH) and many other versatile α,β-unsaturated or α-bromo ketones or aldehydes in large scales to avoid using precious metal compounds.
N-Heterocyclic Carbene-Palladium(II)-1-Methylimidazole Complex Catalyzed α-Arylation of Ketones with Aryl Chlorides
作者:Li-Xiong Shao、Zheng-Kang Xiao
DOI:10.1055/s-0031-1289698
日期:2012.3
An easily available NHC-Pd(II)-Im (NHC = N-heterocyclic carbene, Im = 1-methylimidazole) complex was found to be an efficient catalyst for the α-arylation reaction between ketones and aryl chlorides. Under the optimal conditions, all reactions proceeded smoothly to give the desired products in good to high yields within hours.
A novelcatalyticsystem based on copper(I) and chiral bis(phosphine) dioxides is described. This allows the arylation of silyl enol ethers to access enolizable α-arylated ketones in good yields and enantiomeric excess up to 95%. Noncyclic ketones are amenable substrates with this method, which complements other approaches based on palladium catalysis. Optimization of the ligand structure is accomplished
Carbene-Catalyzed Alkylation of Carboxylic Esters via Direct Photoexcitation of Acyl Azolium Intermediates
作者:Shi-Chao Ren、Wen-Xin Lv、Xing Yang、Jia-Lei Yan、Jun Xu、Fang-Xin Wang、Lin Hao、Huifang Chai、Zhichao Jin、Yonggui Robin Chi
DOI:10.1021/acscatal.1c00165
日期:2021.3.5
A carbene-catalyzed reductive coupling reaction of carboxylic esters and substituted Hantzsch esters is disclosed. Key steps of this reaction include one-electron reduction of a carbene catalyst-bound acyl azolium intermediate to generate the corresponding radical intermediate for subsequent alkylationreactions. The reaction is promoted by irradiation with visible light without the involvement of