Katsuaki Kawasumi, Kenji Mochida, Yasutomo Segawa, and Kenichiro Itami
Tetrahedron, 2013, in press. DOI: 10.1016/j.tet.2013.01.037
We have developed one-step synthesis of multiphenylperylenes from perylene through palladium-catalyzed oxidative C–H/C–B coupling using phenylboroxin as a phenyl source. The combination of Pd(OAc)2 as a catalyst and o-chloranil as an oxidant is the key for direct C–H arylation of perylene. The X-ray crystallography of 3,4,9-triphenylperylene (3) and 3,4,9,10-tetraphenylperylene (4) revealed twisted structures of perylene core caused by steric repulsion of neighboring phenyl groups. Compounds 3 and 4 showed red shift in both absorption and fluorescence spectra compared to perylene whereas absolute fluorescence quantum yields are similarly high (0.94).