Delocalized cationic azo dyes derived from 2-aminoselenazole-5-carbaldehyde

Abstract

Several delocalized cationic azo dyes incorporating a selenazole ring have been prepared by Knoevenagel condensation of an intermediate azo compound bearing a 5-formylselenazole group with methylene bases derived from indolenine, benzothiazole, benzoselenazole, and quinoline. All dyes display a strong absorption at around 700 nm, bathochromically shifted relative to their thiazole analogues, and show a negative solvatochromic behavior. © ARKAT USA, Inc.