Solid-phase catch,activate, and release synthesis of cyanine dyes

reaction: see text] Trimethine cyanine dye was synthesized by capture and activation of a hemicyanine intermediate on sulfonyl chloride resin followed by reaction and concomitant cleavage by a heterocyclic carbon nucleophile. A small array of dyes were synthesized and characterized to demonstrate the versatility of this chemistry for a number of hemicyanines and heterocyclic nucleophiles.