A practical molecular editing strategy has been established for the direct and consecutive C-3 diazenylation and C-2 arylation of indoles with aryltriazenes under metal-free and ambient conditions. A sequence of tandem reactions has been developed via the sustained release of aryldiazonium species from aryltriazenes to achieve the controlled multiple bonds sequential cleavage and formation. This strategy enables the regio- and chemo-controlled consecutive C−H functionalization of indole at two adjacent reactive sites (C-2 versus C-3) without pre-functionalization of the reactive sites and even without the assistance of the directing group, metal catalyst or ligand. Detailed mechanistic experiments and DFT calculations along with supported a sequence of tandem reaction mechanisms. The synthetic importance of this methodology is evident from the simple operation, good functional group tolerance, gram-scale synthesis, late-stage modification of pharmaceuticals and in vitro cytotoxicity evaluation.

Transition-metal-catalyzed cross-coupling of electrophile containing multiple potential coupling sites is often challenging. A straightforward cross-electrophile coupling of aryl iodides and aryltriazenes via photoredox/palladium dual catalysis was developed. The reaction was carried out by using Pd(OAc) 2 as catalyst, Cu(OAc) 2 as promoter, aryltriazenes as arylation reagents and base, various biaryl compounds were afforded under mild conditions. This synergistic method features photoredox/Pd dual catalysis, easily available substrates, gram scale synthesis, synthetic applications, mild, neutral and base-free conditions.