Synthesis, Structure, and Photophysical Properties of Platinum Compounds with Thiophene-Derived Cyclohexyl Diimine Ligands.

Platinum(II) and platinum(IV) compounds were prepared by the stereoselective and regioselective reactions of thiophene-derived cyclohexyl diimine C^N^N-ligands with [Pt2Me4(μ-SMe2)2]. Newly synthesized ligands were characterized by NMR spectroscopy and elemental analysis, and Pt(II)/Pt(IV) compounds were characterized by NMR spectroscopy, elemental analysis, high-resolution mass spectrometry, and single-crystal X-ray diffraction. UV-vis absorbance and photoluminescence measurements were performed on newly synthesized complexes, as well as structurally related Pt(II)/Pt(IV) compounds with benzene-derived cyclohexyl diimine ligands, in dichloromethane solution, as solids, and as 5% by weight PMMA-doped films. DFT and TD-DFT calculations were performed, and the results were compared with the observed spectroscopic properties of the newly synthesized complexes. X-ray total scattering measurements and real space pair distribution function analysis were performed on the synthesized complexes to examine the local- and intermediate-range atomic structures of the emissive solid states.