55919-60-3Relevant academic research and scientific papers
Rhodium(iii)-catalyzed indole synthesis at room temperature using the transient oxidizing directing group strategy
Shang, Yaping,Jonnada, Krishna,Yedage, Subhash Laxman,Tu, Hua,Zhang, Xiaofeng,Lou, Xin,Huang, Shijun,Su, Weiping
supporting information, p. 9547 - 9550 (2019/08/15)
Rh-catalyzed reactions of N-alkyl anilines with internal alkynes at room temperature have been developed using an in situ generated N-nitroso group as a transient oxidizing directing group. Due to mild reaction conditions, this method enabled synthesis of a broad range of N-alkyl indoles, including even two indole-based medicinal compounds. Our work disclosed the feasibility of the transient oxidizing directing group strategy in C-H functionalization reactions, which possesses the potential to enhance overall step-economy and impart new reactivity patterns to substrates.
Rhodium(III)-catalyzed indole synthesis using N-N bond as an internal oxidant
Liu, Baoqing,Song, Chao,Sun, Chao,Zhou, Shuguang,Zhu, Jin
supporting information, p. 16625 - 16631 (2013/12/04)
We report herein a Rh(III)-catalyzed cyclization of N-nitrosoanilines with alkynes for streamlined synthesis of indoles. The synthetic protocol features a distinct internal oxidant, N-N bond, as a reactive handle for catalyst turnover, as well as a hitherto tantalizingly elusive intermolecular redox-neutral manifold, predicated upon C-H activation, for the formation of a five-membered azaheterocycle. The compatibility of seemingly dichotomous acidic and basic conditions ensures reaction versatility for multifarious synthetic contexts. The tolerance of an array of auxiliary functional groups potentially permits predefined, programmable substitution patterns to be incorporated into the indole scaffold. Comprehensive mechanistic studies, under acidic condition, support [RhCp*]2+ as generally the catalyst resting state (switchable to [RhCp*(OOCtBu)]+ under certain circumstance) and C-H activation as the turnover-limiting step. Given the variety of covalent linkages available for the nitroso group, this labile functionality is likely to be harnessed as a generic handle for strikingly diverse coupling reactions.
