The insertion and extrusion of heterosulfur bridges. XVI. Synthesis of triphenyleno[1,12‐bcd:4,5‐b'c'd']dithiophene

Triphenyleno[1,12‐bcd]:4,5‐b′c′d′]dithiophene (3) is synthesized in low yield (2.5% maximum) from a mixture of triphenylene (1) and triphenyleno[4,5‐bcd]thiophene or from 1 alone by means of heterogeneously catalyzed sulfur bridging by hydrogen sulfide at 500–550°. Compound 3 is characterized by spectral and other properties. Hückel molecular orbital calculations for the formation and reaction of 3 are presented.