Syntheses and Studies of the Extended Metal Atom Chains: Deca-nickel String Complex and a Series of Nona-nickel String Complexes

本論文主是以增長鎳金屬串為主要目標，首先以鉑催化進行cross-coupling合成出十氮配基與一系列在末端吡啶基修飾推拉電子基的九氮配基，並進行超長鎳金屬串:十核鎳金屬串與九核鎳金屬串的合成與其性質量測。 首先利用十氮配基H4N10在高溫萘燒的反應條件下可得到全順向配位的十核鎳金屬串[Ni10(N10)4(NCS)2]4+，從磁性的分析可知，末端兩高自旋態的Ni(II) (S = 1)之間為一弱反鐵磁性， J = －0.24 cm-1。與四核鎳金屬[Ni4(μ4-DAniDANy)4(H2O)2]及六核鎳金屬串[Ni6(μ6-bpyany)4(NCS)2]2+比較，主要是隨著末端的兩高自旋的間Ni(II) (S = 1)的距離拉長，其之間的作用力變小，符合在電化學及磁性上所得之結果。 在第二部份，利用一系列分別在末端吡啶基修飾的九氮配基在高溫萘燒的反應條件，同樣都可得到全順向配位的九核鎳金屬串，經由單晶繞射鑑定，在實驗過程中未添加氧化劑與還原劑的情況下，在末端吡啶基修飾推電基的配基可以得到正四價的九核金屬串錯合物：[Ni9(Me2N9) 4Cl2]4+與[Ni9(Ph2N9) 4Cl2]4+；相對地在末端吡啶基修飾拉電基的配基則可以得到正二價的九核金屬串錯合物：[Ni9(Pm2N9) 4Cl2]2+與[Ni9(Pz2N9)Cl2]2+，所以在末端末端吡啶基修飾推電子基可以穩定正四價的九核鎳金屬串錯合物而修飾拉電子基則可以相較穩定還原兩個電子的正二價九核鎳金屬串錯合物，符合在電化學上的結果。之後根據電化學，嘗試將正四價的或正二價的九核鎳金屬串錯合物分別加入還原劑與氧化劑來得到不同組態的九核鎳金屬串。以正四價的九核金屬串[Ni9(Me2N9) 4Cl2]4+為基礎，在不同溶劑中額外添加還原劑後分別可以得到正二價與正一價的九核鎳金屬串錯合物：[Ni9(Me2N9) 4Cl2]2+與[Ni9(Me2N9) 4Cl2]+；而在以正二價的九核金屬串[Ni9(Pm2N9) 4Cl2]4+為基礎，在額外添加還原劑後可以得到正一價的九核鎳金屬串錯合物：[Ni9(Pm2N9)4Cl2]+。A decanickel extended metal atom chains (EMACs) complex with a new pyridyl- and naphthyridyl-modulated ligand (H4bdpdany) was successfully synthesized. The crystal structure of the complex [Ni10(N10)4(NCS)2](PF6)2 shows that all of the N104- ligands bind the metal in an all-syn conformation and X-ray structural studies reveal that the short Ni-Ni distances in the range of 2.36~2.23 Å. The temperature dependent magnetic measurements performed on two independent high spin nickel(II) ions of complex [Ni10(μ10-N10)4(NCS)2](PF6)2 demonstrate that the metal chain is antiferromagnetic. The longer distance between the two terminal high spin nickel(II) ions compared with tetranickel-strings and hexanickel-strings causes the decrease in antiferromagnetic interaction. Second research of nona-nickel string complexes is devoted to investigate the effect of drawing or donating modified ligand. So our group try to synthesize several kinds of bis(2-pyridyl-1,8-naphthyridine-7-yl)amine ligand with modified pyridyl group. Then through our experimental process we could get four plus nona-nickel string complexes with electron-donating modified ligand and two plus nona-nickel string complexes with electron-drawing mortified ligand. According the cycling voltammograms, nona-nickel string complexes with electron-donating modified ligand exhibit three redox couples and one oxide wave and electron-donating modified ligand exhibit four redox couples and two oxide wave. Hence, it’s possible to get the several valences nona-nickel complexes from reacting with the corresponding different oxidant or reductant. X-ray structure studies reveal that the Ni-Ni bond distances have some significant differences (ca. 0.03 Å) between two plus complex and four plus complex. These results reveal that the 1,8-naphthridinyl group could stabilize Ni23+ mixed-valent unit