Air-Stable and Luminescent Trityls via Methoxy Modification

Since the first report of trityl luminescence in 1944, ortho-substituent modification of pristine trityl has been synthetically challenged. So far, air-stable polyhalogenated trityls have shown remarkable luminescent properties. Herein, six air-stable methoxy-substituted trityls (TOMe) were synthesized by stepwise introduction of methoxyl groups, and the effects of the methoxy group on radical stability were systematically studied. Notably, they emit at 588-629 nm with 2.7-4.5% PLQY, 3-5 times higher than the tris(2,4,6-trichlorophenyl)methyl radical, and the PLQY of TOMe2c in the solid film reaches up to 61%, offering an alternative luminescent trityl framework.