Intramolecular hydroamidation of bipyridine platinum(II) acetylide complexes: Synthesis, structures, and properties of bipyridine platinum(II) indolyl complexes

Three bipyridine platinum(II) complexes Pt-2-Pt-4 bearing indolyl ligand(s) have been synthesized through the hydroamidation of acetylide ligand(s) of Pt-1 . The structures of Pt-1-Pt-4 were determined by single crystal X-ray diffraction. The photophysical properties of these structurally related complexes Pt-1-Pt-4 have been studied. Pt-1-Pt-4 in the solid state show emission peaks at 525–570 nm, which are assigned as the mixture of 3 LLCT and 3 MLCT excited states. Solids Pt-1-Pt-4 exhibit mechanoluminescence, and Pt-4G can be recovered back to solids Pt-4 upon adding a few drops of diethyl ether. This study provides a new way to synthesize bipyridine platinum(II) indolyl complexes using intramolecular hydroamidation of alkynyl moieties.