Complexes of Ir(III) and Pt(II) with cyclometallated 2-phenylbenzothiazole and chelating diethyldithiocarbamate and O-ethyldithiocarbonate ions: Structures and optical and electrochemical properties

It is shown by X-ray diffraction analysis, IR spectroscopy, and (1)De, D-13{1H}, and Pt-195 NMR spectroscopy that the Pt(II) and octahedral Ir(III) complexes with metallated 2-phenylbenzothiazole and chelating diethyldithiocarbamate and O-ethyldithiocarbonate ions have the square and cis-C,C structure, respectively. The highest occupied and lowest unoccupied molecular orbitals of the complexes determining their long-wavelength absorption, phosphorescence, and one-electron oxidation and reduction are assigned to those predominantly localized on the mixed p(S)/d(M) and pi* orbitals of the metallated ligand. The cathodic shift of the oxidation voltammogram and the bathochromic phosphorescence shift of the Pt(II) complex with the D-ethyldithiocarbonate ion are attributed to the enhanced donor-acceptor interaction of the donor S atoms of the ligand with Pt(II). The structural data are deposited with the Cambridge Crystallographic Data Centre (CIF files CCDC nos. 1058768 (Ia) and 1058767 (IIb)).