Modified synthetic routes to poly(isothianaphthene)

Two routes for the synthesis of the low bandgap conductive polymer poly(isothianaphthene), which have significant advantages over previous preparative methods, are examined. The single-step O2-induced polymerization of 1,3-dihydroisothianaphthene, which has been reported previously, is further systematically studied. A modified synthetic method for the O2-induced polymerization of 1,3-dihydroisothianaphthene in the presence of the radical initiator dibenzoyl peroxide leads to the more rapid formation of poly(isothianaphthene) in greater yield, and the product shows better stability as a suspension in organic solvents relative to the products of other preparative methods. The products obtained were characterized by elemental analysis, and IR and Raman spectroscopy. The variables involved in these two synthetic routes are investigated and possible mechanisms for the reactions involved are discussed.