New chelating stilbazonium-like dyes from Michler's ketone

Org Lett. 2008 Jan 17;10(2):321-4. doi: 10.1021/ol702793j. Epub 2007 Dec 23.

Abstract

A series of "push-pull" salts substituted with an electron-donating bis(N,N-dimethyl)aniline unit and different electron-withdrawing methyl or chelating pyridinium units have been designed and synthesized from Michler's ketone. The spectroscopic and electronic properties were investigated and compared to their DAST homologues. The studies revealed that a lower HOMO-LUMO gap is obtained in all cases, showing the ability of our donor to increase the "push-pull" effect. Two chromophores with a terpyridine as acceptor end group have also been prepared.