Polymerizations of nitrogen-containing heterophanes by vapor deposition method, transformation to polymeric films bearing a conjugated structure, and their properties

Summary

The polymerizations of three nitrogen-containing heterophanes such as [2.2](2,5)pyridinophane (1), [2.2](2,5)pyrazinophane (2) and N, N′-dimethyl-[2.2](2,5)pyrrolophane (3) by the vapor deposition method were carried out. Compounds1, 2 and3 gave poly(2,5-pyridinediyl-ethylene), poly(2,5-pyrazinediylethylene), and poly(N-methyl-2,5-pyrrolediyl-ethylene) as tough films, respectively. The transformation of the ethylene unit in the polymer films to the vinylene one by the dehydrogenation reaction using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) failed in the former two polymeric films and succeded to a certain extent in the latter one. The electrical conductivity of a poly(N-methyl-2,5-pyrrolediyl-vinylene) film obtained by the dehydrogenation reaction was measured to be 4×10^-4 S/cm at room temperature and increased up to 1×10^-2 S/cm on doping with iodine.