Synthesis and Characterization of NLO Chromophores Containing a 4-cyano-5-dicyanomethylene-2-oxo-3-pyrroline (CDCOP) Acceptor Group

AKIHIRO KANEKO, ZHIKUAN LU, HUI WANG, ROBERT J. TWIEG, GUILIN MAO, KENNETH D. SINGER, and TOSHIKUNI KAINO

Nonlinear-optical chromophores are often comprised of three main structural components: an electron donor, a conjugated p-system and an electron acceptor. We describe here some preliminary results obtained for chromophores that contain a 1-R-3-Ar-4-cyano-5-dicyanomethylene-2-oxo-3-pyrroline (CDCOP) acceptor group (wherein R is H or alkyl and 3-Ar is the attached donor and -system). While first described more than forty years ago this acceptor group has hardly been exploited for any nonlinear optical application. We will discuss some of the special synthetic issues related to this chromophore class as well as their chemical and physical properties compared to other related and better-known chromophores.