Pyrazolato- and 3,5-dimethylpyrazolato-bridged dinuclear platinum(II), palladium(II), and their mixed-metal complexes of 2,2'-bipyrimidine. Syntheses, structures, and luminescent properties

摘要

The pyrazolato (pz)- and 3,5-dimethylpyrazolato (Me_2pz)-bridged dinuclear platinum(II) and palladium(II) complexes of 2,2'-bipyrimidine (bpym), [Pt_2(bpym)_2(μ-pz))2](PF_6)2 (pz' = pz (1a) and Me _2pz (1b)) and [Pd_2(bpym)_2(μ- pz') _2](PF_6)_2 (pz' = pz (2a) and Me_2pz (2b)), have been synthesized and structurally characterized. The PdPt complex,[PdPt(bpym)_2(μ-Me_2pz)_2](PF _6)_2 (4b), has also been synthesized and characterized by 1HNMR spectroscopy. Among these Pt_2, Pd_2, and PdPt complexes, only 1a and 1b exhibit greenish blue and yellow-green luminescence, respectively, in the solid state at ambient temperature. The emissions of 1a and 1b in the solid state are tentatively assigned as the emission from the ~3LC/MLCT and ~3MMLCT excited states, respectively.