Cobalt(III)-Catalyzed Synthesis of Indazoles and Furans by C–H Bond Functionalization/Addition/Cyclization Cascades
作者:Joshua R. Hummel、Jonathan A. Ellman
DOI:10.1021/ja5116452
日期:2015.1.14
reported heterocycle syntheses also demonstrate the use of directing groups that have not previously been applied to Co(III)-catalyzedC–H bond functionalizations. Additionally, the synthesis of furans demonstrates the first example of Co(III)-catalyzedfunctionalization of alkenyl C–H bonds.
Rhodium(III)-Catalyzed Indazole Synthesis by C–H Bond Functionalization and Cyclative Capture
作者:Yajing Lian、Robert G. Bergman、Luke D. Lavis、Jonathan A. Ellman
DOI:10.1021/ja402761p
日期:2013.5.15
An efficient, one-step, and highly functional group-compatible synthesis of substituted N-aryl-2H-indazoles is reported via the rhodium(III)-catalyzed C-H bond addition of azobenzenes to aldehydes. The regioselective coupling of unsymmetrical azobenzenes was further demonstrated and led to the development of a new removable aryl group that allows for the preparation of indazoles without N-substitution. The 2-aryl-2H-indazole products also represent a new class of readily prepared fluorophores for which initial spectroscopic characterization has been performed.
Cyclization of Azobenzenes Via Electrochemical Oxidation Induced Benzylic Radical Generation
作者:Anni Li、Xiangyi Li、Fang Ma、Hui Gao、Hongji Li
DOI:10.1021/acs.orglett.3c02099
日期:2023.8.18
An electrochemical oxidation-induced cyclization of ortho-alkyl-substituted azobenzenes has been developed. The direct electrochemical benzylic C–H functionalization with respect to azobenzenes could proceed in the absence of any catalyst or external chemical oxidant to afford a number of 2H-indazole derivatives in moderate to good yields. This protocol enables the reuse of the byproduct to the same