New push–pull polyene chromophores containing a Michler's base donor and a tricyanofuran acceptor: multicomponent condensation, allopolar isomerism and large optical nonlinearity†
Abstract
The high chemo-selectivity of bis-aldehydes for condensation with both basic and acidic active methylene compounds facilitates a one-pot, three-component reaction to produce dipolar polyene chromophores as the major products for electro-optics.