Complexation of 4,4′-di(tert-butyl)-5-ethynyl-2,2′-bithiazole with mercury(II) ion: Synthesis, structures and analytical applications

Two new mononuclear mercury(II) alkynyl complexes containing substituted bithiazole unit [R–CC–HgMe] (2) and [R–CC–Hg–CC–R] (3) (R = 4,4′-di(tert-butyl)-2,2′-bithiazol-5-yl) were prepared in good yields by mercuration of 4,4′-di(tert-butyl)-5-ethynyl-2,2′-bithiazole (1) at room temperature via the dehydrohalogenation reaction of MeHgCl and HgCl2 with terminal acetylene R–CCH. The structures of the title compounds were characterized by NMR and IR spectroscopy, FAB mass spectrometry, X-ray crystallography and luminescence spectra. A new protocol for derivatization of inorganic and organic mercury(II) ions to mono- and dialkynyl mercury(II) compounds followed by extraction into dichloromethane is suggested, which can be effectively analyzed by HPLC technique using UV detection. The proposed procedure can offer a new opportunity for the simultaneous determination of inorganic Hg(II) and MeHg(II) in aqueous solutions.

Graphical abstractThe synthesis, structure and photophysical properties of some luminescent derivatives of inorganic mercury and methylmercury incorporating 4,4′-di(tert-butyl)-5-ethynyl-2,2′-bithiazole entity were described. These metal complexes can be utilized in the development of a new procedure for derivatization of inorganic and organic mercury(II) to Hg(II) alkynyls for HPLC analysis.Figure optionsDownload full-size imageDownload as PowerPoint slide