A panel of six new arene Ru (II)‐NHC complexes 2a‐f, (NHC = 1,3‐diethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1a, 1,3‐dicyclohexylmethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1b and 1,3‐dibenzyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1c) were synthesized from the transmetallation reaction of Ag‐NHC with [(η6‐arene)RuCl2]2 and characterized. The ruthenium (II)‐NHC complexes 2a‐f were developed as
acceptor-less dehydrogenative coupling (ADC) of alcohols resulted in the synthesis of a series of important α,β-unsaturated functionalized ketones, having aryl, heteroaryl, alkyl, nitro, nitrile and trifluoro-methyl, as well as halogen moieties, with excellent yields and selectivity. Initial mechanistic studies, including deuterium labeling experiments, determination of rate and order of the reaction, and quantitative
Nickel‐Catalyzed Selective Synthesis of α‐Alkylated Ketones via Dehydrogenative Cross‐Coupling of Primary and Secondary Alcohols
作者:Amreen K Bains、Ayanangshu Biswas、Debashis Adhikari
DOI:10.1002/adsc.202101077
日期:2022.1.4
air-stable, homogeneous, nickel catalyst that performs dehydrogenative cross-coupling reaction between secondary and primary alcohols to result α-alkylated ketone products selectively. The sequence of steps involve in this one-pot reaction is dehydrogenation of both alcohols, condensation between the ketone and the aldehyde, and hydrogenation of the in situ-generated α,β-unsaturated ketone. Preliminary
Catalyst-Free Dehydrative α-Alkylation of Ketones with Alcohols: Green and Selective Autocatalyzed Synthesis of Alcohols and Ketones
作者:Qing Xu、Jianhui Chen、Haiwen Tian、Xueqin Yuan、Shuangyan Li、Chongkuan Zhou、Jianping Liu
DOI:10.1002/anie.201308642
日期:2014.1.3
Direct dehydrative α‐alkylation reactions of ketones with alcohols are now realized under simple, practical, and green conditions without using external catalysts. These catalyst‐free autocatalyzed alkylation methods can efficiently afford useful alkylated ketone or alcohol products in a one‐pot manner and on a large scale by CC bond formation of the in situ generated intermediates with subsequent