Facile synthesis of annulated benzothiadiazole derivatives and their application as medium band gap acceptors in organic photovoltaic devices† Xiantao Hu, ‡a Ram Datt,‡b Qiao He, a Panagiota Kafourou, a Harrison Ka Hin Lee, bc Andrew J. P. White,a Wing Chung Tsoi *b and Martin Heeney *a Abstract Two 2,1,3-benzothiadiazole derivatives annulated with 2-(1,3-dithiol-2-ylidene)malonitrile in the 4,5-positions were prepared by nucleophilic substitution reactions of a fluorinated precursor.
