Vapor phase oxidation of poly(1,3-dihydroisothianaphthene)

Exposure of solid poly(1,3-dihydroisothianaphthene) (PDHITN) to thionyl chloride vapor converted it to doped poly(isothianaphthene) (PITN) with a conductivity of 2 S/cm, one of the highest values reported for PITN synthesized by chemical methods. In contrast to dehydrogenation of PDHITN by sulfuryl chloride there was minimal Cl substitution from *the thionyl chloride treatment. The PITN formed was blue, not pale yellow as is obtained with electrochemically oxidized thin films of PITN.