Triangular Trinuclear Cluster Complexes of Platinum (II)

本研究的目标是该化合物的合成、结构、反应活性和电子结构，该化合物的簇核结构是作者团队首次发现的。主要结果如下：1.合成方法的建立。目标化合物来源于四核铂(II)簇合物[Pt4(OAc)8]。三角形铂(II)簇合物可以通过以下两条路线合成，尽管平面内配体仅限于带有乙二胺和乙二胺等氮给体的双齿螯合配体。方法A(基于正方形-平面型簇核变换)。当[Pt4(OAc)8]被允许与给体原子周围空间密集的乙酮肟或二胺反应时，通过核心结构转换得到所需的具有三角形簇核的化合物。方法B(基于方法A制备的络合物的平面配体取代)。当乙二胺或N，N‘-二甲基…更多的乙二胺被用来作为平面内配体，方法A不适用，但通过平面内配体取代得到了所需要的化合物，例如用方法A2合成的乙酮肟配合物。在所有化合物中，簇核结构为等腰三角形。团簇核心中存在直接的铂-铂键。原子核的自旋-自旋耦合常数J_&lt；P_t-P_t&G_t=7500-8000 Hz。EHMO计算表明，这种类型的团簇核心是电子稳定的，三角形顶端的铂原子是以铂-铂单键结合的。4.团簇平面上配体的替代不稳定性。我们原以为[Pt4(OAc)8]中的[Pt4(OAc)8]中的[Pt4(OAc)8]具有正方形-平面型核，通过反式作用使其不稳定。然而，结果表明，没有明显的不稳定性。这是由于以下几个原因。所有化合物的平面位置都有氮施主配体，且铂-氮键比铂-氧键强得多。此外，乙二酮肟络合物在团簇平面上存在分子内氢键。较少

The objective of the present study is synthesis, strucuture, reactivity, and electronic structure of the titled compound whose cluster core structure has been found for the first time by the author's group. Main reults are as follows.1.Establishment of the synthetic method. Desired compounds are derived from tetranuclear platinum (II) cluster complex, [Pt_4 (OAc) _8]. Triangular platinum (II) cluster complexes can be prepared via following two routes, although in-plane ligands are limited to bidentate chelate ligand with nitrogen donors such as glyoxime and diamines.Method A (based on cluster core transformation from the square-planar type). When [Pt_4 (OAc) _8] is allowed to react with glyoximes or diamins in which the surroundings of donor atoms are sterically crowded, desired compounds with the triangular cluster core are prepared through core structure transformation.Method B (based on in-plane ligand substitution of complexes made by Method A). When ethylenediamine or N,N'-dimethy … More lethylendiamine are used as in-plane ligand, Method A is not applicable, but desired compounds are obtained by in-plane ligand substituion of, e.g., glyoxime complexes prepared by Method A.2.Structural studies by means of ^<l95>Pt-, ^<l3>C-, ^1H-NMR and X-ray analyzes. In all the compounds, the cluster core structure was an isosceles triangle. There exist direct Pt-Pt bonds in the cluster core. Magnitude of neclear spin-spin coupling constant J_<Pt-Pt> was 7500-8000 Hz.3.Electronic Structure of the triangular cluster core. EHMO calculation shows that the cluster core of this type is electronically stable, and that platinum atoms at the apices of the triangle are bound by Pt-Pt single bond.4.Substitution lability of the ligand which is in the cluster plane. We had expected labilization by the trans effect of the Pt-Pt bond as in [Pt_4 (OAc) _8] with the square-planar core. Results shows, however, no marked labilization. This is due to the following reasons. All the compounds prepared in this study have nitrogen donor ligands at the in plane sites and Pt-N bond is much stringer than Pt-O bond. Further, glyoxime complexes have intra-molecular hydrogen bonds in the cluster plane. Less