Synthesis of 3-Vinylpyrene by Wittig’s Reaction, and Syntheses and Electrical Properties of Polyvinylpyrene and Its Charge Transfer Complexes

Using Wittig’s reaction, we synthesized 3-vinylpyrene from pyrene-3-aldehyde in 76% yield. 3-Vinylpyrene monomer was polymerized by benzoylperoxide or di-t-butylperoxide catalysts. Each polymer had a melting point, being observed by the method of polarizing hot stage microscopic examination. X-ray examination showed that the polymer was crystalline, although rather poor. The charge transfer complexes, containing polyvinylpyrene as an electron donor, and iodine, tetracyanoethylene or tetracyanoquinodimethane as an electron acceptor, were prepared, each having the composition of pyrene nucleus : acceptor=16 : 3, 15 : 2, 15 : 2, respectively. Electrical conductivities of the complexes at 25°C, ρ25 and band gap energies, ε, were 1.3×108 Ωcm, 0.80 eV; 4.5×1012 Ωcm, 1.32 eV; 1.1×1014 Ωcm, 1.34 eV, respectively. Each complex showed ohmic current-voltage characteristics in an appropriate temperature range.