Rhodium-catalyzed directed C–H functionalization of 2-arylindazoles with diazotized Meldrum's acid

A rhodium-catalyzed alcohol-mediated ortho-functionalization of 2-aryl-2H-indazoles through sequential C-H activation and carbenoid insertion with diazotized Meldrum's acid was developed. Using the 2H-indazole as the directing group and alcohol as the alkyl source, a series of ortho-alkylated aryl-2H-indazoles were obtained over a wide structural scope with high site-selectivity and excellent functional-group tolerance.