Mixed-ligand platinum(II) complexes containing 2-(2′-pyridyl)phenyl and 8-quinolylphosphines: Synthesis and molecular structures in the crystals and in solution
Mixed-ligand platinum(II) complexes containing 2-(2′-pyridyl)phenyl and 8-quinolylphosphines: Synthesis and molecular structures in the crystals and in solution
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DOI：
10.1016/j.ica.2020.119862
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发表时间：
2020-11
影响因子：
2.8
通讯作者：
Masatoshi Mori;Takayoshi Suzuki
中科院分区：
文献类型：
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作者：
Masatoshi Mori;Takayoshi Suzuki
制备了一系列含有8-喹啉基膦的环金属化{2-（2 '-吡啶基）苯基}铂（II）配合物：8-（二甲基膦基）喹啉（L1）、8-（二苯膦基）喹啉（L2）、2-甲基-8-（二苯膦基）喹啉（L3）和2-苯基-8-（二苯膦基）喹啉（L4），并对其分子结构和光谱性质进行了研究。产物[Pt（ppy）（Ln）]（BF 4或OTf）{Cn;n=1-4，ppy−= 2-（2′-吡啶基）苯基，OTf−=三氟甲磺酸盐}的单晶X射线分析和~（31）P {1H} NMR谱表明，配合物阳离子为顺式（P，C）构型，但正方平面的Pt Ⅱ配位构型发生了相当大的畸变。特别是在含有空间要求高的8-喹啉基膦（L3和L4）的配合物C3和C4中，不仅PtII配位球的四面体畸变，而且PtII中心偏离平面螯合环，即，观察到螯合喹啉基膦配位的扭曲型畸变。所有配合物在溶液中对卤素阴离子的加成是稳定的。然而，在温度依赖的1H NMR谱中观察到由于扭曲的配位球的限制性反转，络合物C3和C4的流动行为。
A series of cyclometalated {2-(2′-pyridyl)phenyl}platinum(II) complexes having 8-quinolylphosphines, 8-(dimethylphosphino)quinoline (L1), 8-(diphenylphosphino)quinoline (L2), 2-methyl-8-(diphenylphosphino)quinoline (L3), and 2-phenyl-8-(diphenylphosphino)quinoline (L4), were prepared and their molecular structures and spectroscopic properties were investigated. The single-crystal X-ray analysis and the31P{1H} NMR spectra of the products, [Pt(ppy)(Ln)](BF4or OTf) {Cn;n=1–4, ppy−= 2-(2′-pyridyl)phenyl, OTf−= trifluoromethanesulfonate} revealed thecis(P,C)configuration of the complex cations, although the square-planar PtIIcoordination geometry was considerably distorted. In particular, in the complexesC3andC4bearing sterically demanding 8-quinolylphosphines (L3andL4), not only the tetrahedral distortion of the PtIIcoordination sphere but also a deviation of the PtIIcenter from the planar chelate ring, i.e., an envelope-type distortion of the chelating quinolylphosphine coordination was observed. All complexes were stable in solution toward the addition of halide anions. However, a fluxional behavior of complexesC3andC4, owing to the restricted inversion of the distorted coordination sphere, was observed in the temperature-dependent1H NMR spectra.