K2S2O8-HFIP synergistically promoted para-selective sp3 C-H bond diarylation of glycine esters.

A metal-free K2S2O8-HFIP synergistically promoted double Friedel-Crafts alkylation between a glycine derivative and N-substituted aniline was developed to efficiently synthesize diarylmethane derivatives with high para-selectivity. The reaction proceeded smoothly in the absence of any metal and ligand, and exhibited a good tolerance of functional groups.