A catalyst-free photoarylation of 2-aryl-2H-indazoles by carbon–iodine bond activation has been developed for the synthesis of C3-arylated indazoles in moderate to good yields.
Synthesis of functionalized benzo[a]phenazines and indazolo[2,3-a]quinolines has been developed through Rh(III)-catalyzed oxidative annulation of 2-aryl-2H-indazoles and 2-arylquinoxalines with allyl alcohols, respectively.
A CH3OK catalyzed [5+1] annulation was developed using a newly designed allene with 1,5-biselectroephilic properties.
A novel strategy for the catalytic synthesis of 2-aryl-2H-benzo[d][1,2,3]triazoles bearing various functional groups in good to excellent yields by non-noble molybdenum-catalyzed deoxygenative heterocyclization of 2-nitroazobenzenes is described.
The advancements in the synthesis of nitrogen-containing heterocycles via Rh(III)-catalyzed chelation-assisted tandem C–H activation/carbene insertion/annulation with diazo compounds as carbene precursors have been summarized.