Palladium-Catalyzed Synthesis of 2-Cyanoindoles from 2-gem-Dihalovinylanilines.

An efficient Pd(0)-catalyzed synthesis of 2-cyanoindoles from 2-gem-dihalovinylanilines is reported. Few methods have aimed to synthesize these scaffolds, which are found in many natural products and have high bioactivity. This protocol features a robust catalyst system utilizing Zn(TFA)2 to prolong the catalytic activity. Additionally, the amount of cyanide in the reaction phase is minimized by taking advantage of the solubility of Zn(CN)2 in a two-solvent mixture.