Metal-Catalyzed Synthesis of a Monomethine Cyanine

A new ZrCl 4 -catalyzed method for the preparation of an asymmetrical benzimidazole derivative has been developed. Further alkylation of the benzimidazole precursor with methyl iodide afforded a new monomethine cyanine derivative. The photophysical evaluation showed that the newly synthesized monomethine cyanine compound was non-fluorescent.