Synthesis and crystal structure of a highly selective colorimetric and fluorometric sensor for hydrogen sulfide

A novel Cu(II) complex chemosensor for hydrogen sulfide with azo as the colorimetric group has been synthesized. The complex and ligand crystals were obtained and the molecular structures were characterized by X-ray diffraction and Electrospray ionization High resolution mass spectrometer (ESI-HRMS). The photophysical and recognition properties were examined. The complex can recognize S 2 − , with an obvious color change from yellow to red based on a copper ion complex displacement mechanism. By contrast, no obvious changes were observed in the presence of other anions (AcO − , H 2 PO 4 − , F − , Cl − , Br − and I − ). We present a simple, easily prepared, yet efficient, inorganic reaction-based sensor for the detection of S 2 − . The complex should have many chemical and analytical applications in the sensing of hydrogen sulfide.