Binuclear platinated 2-phenylbenzothiazole complexes with bridging 2-mercapto derivatives of thiazoline, 1-methylimidazole, and pyrimidine: Structures and optical and electrochemical properties

Abstract

The structures of complexes [Pt(Bt)(μ-(N^S))]2 with platinated 2-phenylbenzothiazole (Bt) and bridging 2-mercapto derivatives (N∧S) of thiazoline, 1-methylimidazole, and pyrimidine in the crystalline state and in a CDCl3 solution are studied by X-ray diffraction analysis and 1H, 13C, and 195Pt NMR spectroscopy. Complexes [Pt(Bt)(μ-(N^S))]2 have the cis-N(Bt),S(N^S) structure with the Pt-Pt chemical bond (2.89–2.93 A) and antisymmetrical position of two cycloplatinated and two bridging ligands (CCDC nos. 1001204 (I), 1027021 (II), and 993566 (III)). The long-wavelength absorption bands (410–540 nm), phosphorescence bands with λmax = 685 nm, and two-electron electroreduction (E p = −(2.00–2.27) V) and oxidation (E p = 0.07–0.20 V) processes are assigned to photo- and electrostimulated processes involving the LUMO and HOMO predominantly localized on the π* orbitals of {Pt(Bt)} and on the σ* orbitals of the metal-metal chemical bond.