Synthesis and Structure of NLO-active 8,8-Dicyano-3-(4-N,N-dimethylamino)phenylheptafulvene

Some new 8,8-dicyanophenylheptafulvene derivatives have been synthesized, among which the title compound la is found to crystallize in the polar space group of P1 showing non-linear optical characteristics. Compound la is composed of a strong acceptor of the dicyanomethylene group and a strong donor of the dimethylamino group, both of which are combined with the (pi)-conjugated phenylheptafulvene skeleton.