Indoles and its derivatives represent an important class of nitrogen-containing heterocycles in many natural products and pharmaceuticals.Although great efforts in the construction of indole skeleton have been made,new methods are still desirable.Most current methods require expensive transition metal catalysts,harsh conditions or suffer from low selectivity.Herein we report a new method for the synthesis of 2,3-diaryl-indoles.The reaction could be conducted under mild conditions and required no transition metal catalysts.Various 2,3-diarylsubstituded indoles were obtained in moderate to high yield.The hydroxyl substitution on the diphenylmethane had a significant impact on this transformation.Radical scavenger such as TEMPO,DPPH and molecular oxygen inhibited completely the reaction.The reaction was proposed to proceed via a radical pathway.The ketyl radical was generated as the reactive intermediate for the subsequent addition to the imine group.