Substrate-controlled Rh(<scp>iii</scp>)-catalyzed regiodivergent annulation towards fused and spiro benzimidazoles
作者:Ying-Ti Huang、Indrajeet J. Barve、Yi-Ting Huang、Sandip Dhole、Wei-Jung Chiu、Chung-Ming Sun
DOI:10.1039/d2ob00906d
日期:——
Mechanistically, C–H activation followed by migratory insertion of maleimide forms a Heck-type intermediate. Unsubstituted benzimidazole undergoes aza-Michael addition to form a (4 + 2) fused product, whereas ortho-substituted phenyl benzimidazole causes steric clash to deliver a (4 + 1) spiro-adduct favorably via acid-catalyzed intramolecular annulation.
rylimidazoles with iodonium ylides leading to substituted tetracyclic and pentacyclic bridgehead N-heterocycles, wherein iodonium ylide acts as a carbene precursor. For the first time, iodonium ylide proceeds through a Ru–carbenoid intermediate. Further, the synthetic utility of this protocol was successfully shown for gram-scale synthesis and useful synthetic transformations.
Metal-Free TEMPO-Promoted C(sp<sup>3</sup>)–H Amination To Afford Multisubstituted Benzimidazoles
作者:Ding Xue、Ya-Qiu Long
DOI:10.1021/jo5005179
日期:2014.5.16
An efficient TEMPO-air/cat. TEMPO-O-2 oxidative protocol was developed to synthesize multisubstituted or fused tetracyclic benzimidazoles via a metal-free oxidative C-N coupling between the sp(3) C-H and free N-H of readily available N-1-benzyl/alkyl-1,2-phenylenediamines.
Chemoselective Installation of Diverse Succinimides on Fused Benzimidazoles via Rhodium-Catalyzed C–H Activation/Annulation: Chemosensor for Heavy Metals
作者:Mohammad Aslam、Sonaimuthu Mohandoss、Yong Rok Lee
DOI:10.1021/acs.orglett.1c01793
日期:2021.8.20
Cascade C–H Activation and Defluorinative Annulation of 2-Arylbenzimidazoles with α-Trifluoromethyl-α-diazoketones: Modular Assembly of 6-Fluorobenzimidazo[2,1-<i>a</i>]isoquinolines
作者:Zhongkang Dong、Hengzhi Zhang、Baiquan Wang、Bin Li