General and Mild Ni<sup>0</sup>-Catalyzed α-Arylation of Ketones Using Aryl Chlorides
作者:José A. Fernández-Salas、Enrico Marelli、David B. Cordes、Alexandra M. Z. Slawin、Steven P. Nolan
DOI:10.1002/chem.201406457
日期:2015.3.2
A general methodology for the α‐arylation of ketones using a nickel catalyst has been developed. The new well‐defined [Ni(IPr*)(cin)Cl] (1 c) pre‐catalyst showed great efficiency for this transformation, allowing the coupling of a wide range of ketones, including acetophenone derivatives, with various functionalised arylchlorides. This cinnamyl‐based Ni–N‐heterocyclic carbene (NHC) complex has demonstrated
已经开发了使用镍催化剂对酮进行α-芳基化的一般方法。定义明确的新型[Ni(IPr *)(cin)Cl](1 c)预催化剂显示出极高的转化效率,使各种酮(包括苯乙酮衍生物)与各种官能化的芳基氯化物偶合。这种基于肉桂基的Ni-N-杂环卡宾(NHC)配合物表现出与以前报道的NHC-Ni催化剂不同的行为。初步的机理研究表明,Ni 0 / Ni II催化循环起作用。
Progress in the Palladium-Catalyzed α-Arylation of Ketones with Chloroarenes
Non- and deactivated chloroarenes can be coupled with a wide range of ketones to yield the corresponding arylmethyl ketones in good to excellent yields using a palladium(II) acetate/n-BuPAd2 catalyst system. Depending on the ketone, the chloroarene/ketone ratio and the base, mono or diarylation can be effected selectively.
A reductive cross coupling reaction process for functionalization of a nucleophilic alkene can be achieved. The nucleophilic alkene and a nucleophilic cross coupling partner compound can be reacted in the presence of an oxidizable alcohol and a suitable catalyst to form a reductive coupling product. Various additives can also be useful to refine the process such as by mitigating certain undesirable intermediates, facilitating specific site selectivity for various substitutions or reaction sites, etc. Chiral additives can be optionally used which act to provide asymmetric catalysis, e.g. allow for regioselective and stereoselective production of reductive coupling products. A reductive cross coupling pathway can include oxidizing the oxidizable alcohol to form a catalyst hydride. The nucleophilic alkene can be inserted into the catalyst hydride to form a catalyst-alkyl intermediate. Further, the catalyst-alkyl intermediate can be transmetallized with the nucleophilic cross coupling partner compound to form a transmetallated intermediate. The catalyst can be reductively eliminated to form the reductive coupling product and a reduced catalyst. Finally, the reduced catalyst can be oxidized under aerobic conditions, for example with oxygen, to form the oxidized catalyst and subsequent repetition through the cyclic pathway.