Understanding the optical effects of substituting on the 1,8 and 1,5 positions of corannulene

Corannulene's outer rim was regio-selectively functionalized with ethynyl units at both 1,8 and 1,5 positions and later coupled with phenyl and anthracenyl moieties to study the extent of conjugation through the aromatic framework of corannulene via absorption/emission spectra. Experimental observations were compared with TD-DFT calculations at the level of CAMB3LYP/6-31G* and B3LYP/6-31G*. Laser excitation experiments reveal blue emission for 1,8-bis(phenylethynyl)corannulene and 1,5-bis(phenylethynyl)corannulene which quickly transforms into intense blueish-green in the case of 1,8-bis(9-anthranyl)corannulene and 1,5-bis(9-anthranyl)corannulene. (C) 2017 Elsevier Ltd. All rights reserved.