An efficient catalyst-free C-O bond formation reaction for the synthesis of 1H-indol-3-yl benzoates was developed through C(sp2)-H functionalization of 1H indoles with benzoyl peroxide (BPO) in acetonitrile at room temperature under open flask conditions. The reaction proceeds without exclusion of air or moisture and is applied to a wide array of electronically differentiated indoles as well as BPOs. C-3 benzoxylation of indoles was achieved with excellent regioselectivity under mild and easy to operate conditions. The reaction is scalable to one gram level.