AN ISOMERIC SERIES OF THIOPHENE-FUSED TETRACYANOQUINODIMETHANES .1. PREPARATION AND PHYSICOCHEMICAL PROPERTIES

Four isomeric benzodithiophene analogs of 11,11,12,12-tetracyano-9,10-anthraquinodimethane have been prepared via a TiCl4 mediated condensation of the corresponding quinone and malononitrile. potential of these isomers was interpreted in terms of the resonance energies for the neutral and radical anion species. These new acceptor compounds, except for 4,8-bis(dicyanomethylene)4,8-dihydrobenzo[1,2-c:4,5-c]-dithiophene, formed crystalline charge-transfer complexes with tetrathiafulvalene, among which the complex of 4,8-bis(dicyanomethylene)-4,8-dihydrobenzo[1,2-b:4,5-b']dithiophene particularly exhibited a high room-temperature conductivity of 4.78 S cm-1.