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顺-Ru(bpy)2(NO2)2和反-Ru(bpy)2(NO2)2(bpy=2,2′-联吡啶)组成完全相同,但配合物的构型不同。反-Ru(bpy)2(NO2)2和反-Ru(py)4(NO2)2(py=吡啶)两个配合物构型相同,辅助配体相同,但主配体有差异。本文通过在不同或相似条件下,上述三个配合物中辅助配体NO2-在酸催化下的反应结果的对比,探讨了配合物中的NO2-在酸催化下的反应机理(缔合或解离)与配合物构型、配体结构以及配体反式效应性质之间的关系。当反应配体对位为NO2-等反式效应较强的基团时,反应倾向于以解离机理发生配体取代反应。若对位为OH-等反式效应较弱的基团时,倾向于发生NO2-配体的分解反应。在顺式联吡啶二硝基化合物中,酸催化下只发生配体分解反应。通过对比得出,处于反应配体(NO2-)反位的配体的性质,特别是反式效应性质的强弱,会明显影响或改变配体取代反应的机理(解离或缔合)或反应类型(取代或分解),有时甚至是影响反应机理或反应方式的主要因素。无论在反式还是在顺式构型的配合物中,bpy的约束构型会影响过渡态的稳定性,进而影响反应发生的机理。
The composition of cis-Ru (bpy) 2 (NO2) 2 and trans-Ru (bpy) 2 (NO2) 2 (bpy = 2,2’- bipyridine) are identical but the configurations of the complexes are different. The two complexes of trans-Ru (bpy) 2 (NO2) 2 and trans-Ru (py) 4 (NO2) 2 (py = pyridine) have the same configuration with the same ancillary ligand but different ligands. In this paper, under different or similar conditions, the three ligands in the coordination ligand NO2-acid-catalyzed reaction results compared to explore the reaction of NO2-in the catalyst under acid catalysis (association or solution The relationship between the configuration of the complex, the structure of the ligand and the trans effect of the ligand. When the reactive ligand para to NO2- and other trans-strong groups, the reaction tends to dissociate ligand exchange reaction. When the para-OH- group has a weak trans-effect, the NO2-ligand decomposition reaction tends to occur. In cis-bipyridyl dinitro compounds, only acid-catalyzed ligand decomposition reaction. By comparison, it is concluded that the nature of the ligand at the trans-position of the reactive ligand (NO2-), in particular the strength of the trans-acting nature, significantly affects or alters the mechanism of the ligand displacement reaction (dissociation or association) or The type of reaction (substitution or decomposition), and sometimes even the major factor that affects the reaction mechanism or mode of reaction. Whether in the trans or cis configuration of the complex, bpy the confinement configuration will affect the stability of the transition state, thereby affecting the reaction mechanism.