1,3,4,6,7,9-Hexamethylbenzo[1,2-c:3,4-c’:5,6-c’’]trithiophene: a twisted heteroacene

Abstract

1,3,4,6,7,9-Hexamethylbenzo[1,2-c:3,4-c:5,6-c]trithiophene ( C-Me) was prepared by palladium-catalyzed methylations of the corresponding hexabromide C-Br. The twisted structure of C-Me has been confirmed by X-ray crystal analysis. The physical properties of twisted C-Me and planar benzo[1,2-c:3,4-c:5,6-c]trithiophene ( C-H) were studied and compared. Crystal structures are compared to computational structures determined using density functional theory, with both the M06-2X and B3PW91 functionals.