title: A simple route to phosphamethine cyanines from S,N-heterocyclic carbenes.
abstract: Although salts of thiazolium cations are known, many readily prepared iodide salts have eluded spectroscopic and structural characterization; herein, data for a variety of such salts are reported. It has been demonstrated that thiazolium cations can be deprotonated to generate S,N-heterocyclic carbenes and their "electron rich olefin" dimers, but use of the former has been largely overshadowed by that of the more common N-heterocyclic carbenes. We report herein that the deprotonation of thiazolium iodides and their subsequent reaction with a conveniently prepared triphosphenium precursor grants phosphamethine cyanine cations with solid-state geometry and electronic structure unlike those of NHC-stabilized cations. Protection of the phosphorus atom in such ions with elemental sulfur provides an air- and moisture-stable dithiophosphinium salt.
authors.affiliation: Department of Chemistry and Biochemistry, Windsor, Ontario, CanadaN9B 3P4. cmacd@uwindsor.ca.
authors.forename: Justin F
authors.initials: JF
authors.lastname: Binder
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Corrente
authors.forename: Charles L B
authors.initials: CL
authors.lastname: Macdonald