‡ These authors contributed equally Dedicated to Professor Dieter Enders Abstract A cationic ruthenium(II)-complex enabled unprecedented C–H methylations on indoles and pyrroles. The versatile catalyst proved to be widely applicable and delivered the methylated heteroarenes with excellent levels of positional selectivity and ample substrate scope. The robustness of the catalysts was reflected by the
Tandem Rh(III)-Catalyzed C–H Amination/Annulation Reactions: Synthesis of Indoloquinoline Derivatives in Water
作者:Liangliang Shi、Baiquan Wang
DOI:10.1021/acs.orglett.6b01234
日期:2016.6.17
Rh(III)-catalyzed synthetic method for indoloquinoline derivatives from readily available indoles and isoxazoles was developed. This annulation procedure undergoes tandem C–H activation, cyclization, and condensation steps. In this domino cyclization reaction, water is an efficient solvent. A catalytically competent five-membered rhodacycle has been isolated and characterized, thus revealing a key intermediate
Selectivity control in hydroarylation‐based C−H alkylation has been dominated by steric interactions. A conceptually distinct strategy that exploits the programmed switch in the C−H activation mechanism by means of cobalt catalysis is presented, which sets the stage for convenient C−H alkylations with unactivated alkenes. Detailed mechanistic studies provide compelling evidence for a programmable switch
Expedient C−H additions of heteroarenes onto aldimines were realized by a sustainable manganese catalysis manifold within a removable directing group strategy. The C−Hactivation features most user‐friendly reaction conditions, excellent chemo‐ and position‐selectivity as well as ample substrate scope. Detailed experimental mechanistic studies suggest an organometallic C−H manganesation mode of action
applicable C−H functionalization platform enabled the step‐economical transformation of aldehydes, ketones, and imines under additive‐free reaction conditions. In contrast to palladium, rhodium, ruthenium, rhenium, iridium, nickel, and cobalt catalysis, solely manganese(I) complexes outcompeted the innate substrate control, clearly highlighting the unique power of manganese(I) C−H activation catalysis
C = Het键(Het =杂原子)的便捷加氢芳基化是通过用户友好的有机金属CH活化以位置选择的方式完成的。广泛适用的CH功能化平台可在无添加剂的反应条件下实现醛,酮和亚胺的分步经济转化。与钯,铑,钌,rh,铱,镍和钴的催化作用相反,仅锰(I)配合物的竞争能力超过了先天的底物控制,这清楚地突出了锰(I)CH活化催化的独特能力。