| Summary: | 碩士 === 中原大學 === 化學研究所 === 89 ===
Abstract
This thesis discusses the supramolecular chemistry of transition metal halide complexes, which have been determined by X-ray crystallography and characterized by FT-IR, 1H-NMR, TGA and DSC.
The complexes [H(2-ampy)]2[PtCl4] 1, [H(2-ampy)]2[CuCl4] 2, [H(2-ampy)]2[SnCl6] 3, [H(2-ampy)]4[Hg2Cl6]2 4, and [H(2-ampy)]2[PdCl4] 5 (2-ampy = 2-Aminopyridine) were prepared by reactions of 2-aminopyridine with appropriate metal halide in HCl. An unprecedented four-center (trifurcated) hydrogen bond involving two Npyridine-H---Cl and one Npyridine-H---Pt interactions was found in complex 1. In complex 3, both three-center and four-center hydrogen bonding of the types Sn-Cl---H2 and Sn-Cl---H3 were observed, which are important in cross-linking the metal layers and the [H(2-ampy)]+ cations. Complex 4 contains doubly edge-sharing bitetrahedral [Hg2Cl6]2- anions, which form linear chains through weak Hg---Cl interactions. The structural role of [H(2-ampy)]+ in these complexes to control the aggregation of the metal ions is discussed.
The complexes [H(2,6-diampy)]2[SnCl6] 6, [H(2,6-diampy)]6{[Hg2Cl6][HgCl4]2} 7, [H(2,6-diampyBr)]3[CuBr4] 8, [H(2,6-diampy)]2[CuBr2] 9, [H(2,6-diampy)][CdCl3] 10 (2,6-diampy = 2,6-diaminopyridine) were prepared by reaction of 2,6-diaminopyridine with appropriate metal halide in HCl or HBr. In these structures, various types of hydrogen bonds are used to create larger molecular arrays. Most importantly, Npyridine-H---X and Namine-H---X (X = Cl, Br) interactions are used to link the metal units to the protonated 2,6-Diaminopyridine. In complex 6, both three-center and four-center hydrogen bonding of the types Npyridine-H---Cl2, Namine-H---Cl2 and Sn-Cl---H2 are observed. Complex 7 contains two isolated [HgCl4]2- and one [HgCl4]2- anions, in which the [HgCl4]2- anions are edge-sharing with [HgCl4]2- to form a linear tetranuclear complexes through weak Hg---Cl interactions. Complex 8 contains a unique, isolated tetrahedral [CuBr4]3- anion, which is stabilized by extensive Npyridine-H---Br, Namine-H---Br and C-H---Br hydrogen bonding. The pyridine rings of the original 2,6-diaminopyridine compounds have undergone bromoation during the synthesis process and was accompanied by reduction of the Cu(II) ion to Cu(I). The structure of 9 consists of anionic chains of doubly edge-sharing copper (I) metal centers through bromide atoms. The {[CuBr2]n}n- linear chains are linked into two-dimensional molecular sheets through the Npyridine-H---Br and Namine-H---Br interactions (2.582 to 2.951 Å).
The complexes [H(R-mba)]2[CuCl4] 11, [H(S-mba)]2[CuCl4] 12, (R-mba = R-(+)-α-Methylbenzylamine; S-mba = S-(-)-α-Methylbenzylamine) were prepared by reactions of CuCl2 with R-mba and S-mba, respectively, in HCl. In these complexes Npyridine-H---Cl and Namine-H---Cl interactions are used to link the metal units to the protonated R-(+)-α-Methylbenzylamine and S-(-)-α-Methylbenzylamine. Both three-center hydrogen bondings were observed in the complexes.
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