Synthesis and solution fluxionality of rhenium(<scp>I</scp>) carbonyl complexes of 2,4,6-tris(pyrazol-1-yl)-1,3,5-triazines (L), [ReX(CO)<sub>3</sub>L](X = Cl, Br or I). Characterization of [{ReX(CO)<sub>3</sub>}<sub>2</sub>L](X = Cl or Br)
作者:Andrew Gelling、Keith G. Orrell、Anthony G. Osborne、Vladimir Šik
DOI:10.1039/dt9960003371
日期:——
The stable octahedral complexes fac-[ReX(CO)3L][X = Cl, Br or I; L = 2,4,6-tris(4-methylpyrazol-1-yl)-1,3,5-triazine (tmpzt) or 2,4,6-tris(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine (tdmpzt)] have been prepared in which the substituted triazines act as bidentate chelate ligands. In solution the complexes are fluxional with the nitrogen ligand oscillating between two equivalent bonding modes. Rates and
稳定的八面体络合物fac- [ReX(CO)3 L] [X = Cl,Br或I; L = 2,4,6-三(4-甲基吡唑-1-基)-1,3,5-三嗪(tmpzt)或2,4,6-三(3,5-二甲基吡唑-1-基)-1 [3,5-三嗪(tdmpzt)]已经制备,其中取代的三嗪充当二齿螯合配体。在溶液中,络合物是通量的,氮配体在两种等效的键合模式之间振荡。通过动态NMR方法已经研究了通量的速率和活化能。活化能ΔG ‡(298.15 K)在47–72 kJ mol –1的范围内,并且取决于吡唑基团的空间要求。在低温下变化11 H NMR光谱是根据未配位的吡唑环之一的变化的旋转速率来解释的。还分离了非助流性双金属配合物[ReX(CO)3 } 2 L](X = Cl或Br; L = tdmpzt),并通过1 H NMR光谱对其结构进行了表征。