摘要
以實驗室先前合成的P(C6H3-3-SiMe3-2-S)3能產生出一系列鎳三價 錯合物為想法出發，改合成出P(C6H4-2-N(CH3)2)3，期許能以其產生出鎳一價錯合物，並研究其對小分子的活化。 將NiII(ClO4)2•6H2O等比例加入P(C6H4-2-N(CH3)2)3並溶於MeCN中，於室溫、氮氣環境下可以得到[NiII(NCMe)2(OH2)(P(C6H4-2-N(CH3)2)3)][ClO4]2 (1)，利用X-ray單晶繞射解析、超導量子干涉儀、電子順磁共振光譜儀、核磁共振儀、IR光譜儀和UV-Vis光譜儀鑑定錯合物1，可知鎳金屬為正二價high-spin且含兩個未成對電子，六配位扭曲的八面體結構。此外，可改用Ni粉及[NO][BF4]溶於MeCN中，合成出[Ni(NCMe)6][BF4]2，再與等比例的P(C6H4-2-N(CH3)2)3反應後得到[NiII(NCMe)2(OH2)(P(C6H4-2-N(CH3)2)3)][BF4]2 (2)，來達成改變陰離子的目的。 將錯合物1或2與當量的KC8於低溫、氮氣下的環境反應可以生成[NiI(NCMe)2(P(C6H4-2-N(CH3)2)3)][X] (X = ClO4或BF4) (3)，利用UV-Vis與EPR光譜可以測得錯合物3的訊號，發現錯合物3對氧氣敏感，並推測其Ni中心金屬只與ligand上之P原子及兩個solvent (-NCCH3)的氮原子有配位，形成扭曲平面三角形結構。在活化小分子方面，錯合物3可和CS2、CO2反應，推測會產生[NiIII(η2-CS2)(P(C6H4-2-N(CH3)2)3)]及[NiIII(η2-CO2)(P(C6H4-2-N(CH3)2)3)]，由UV-Vis光譜及EPR來鑑定產物。 將[NiIII(η2-CS2)(P(C6H4-2-N(CH3)2)3)]加入等當量的KC8於低溫、氮氣下反應，得到[NiII(η2-CS2)(P(C6H4-2-N(CH3)2)3)] (4)，利用X-ray、UV-Vis、IR、1H NMR鑑定錯合物4的鎳金屬為正二價low-spin，四配位扭曲的平面四邊形結構。
並列摘要
The previously synthesized P(C6H3-3-SiMe3-2-S)3 can serve as a ligand to produce a series of nickel(III) complexes.Here we synthesize P(C6H4-2-N(CH3)2)3, expected to produce Ni(I) complex, and study its effect on the activation of small molecules. The NiII(ClO4)2 • 6H2O reacting with P(C6H4-2-N(CH3)2)3 (1:1 molar ratio) in MeCN at room temperature under dinitrogen atmosphere yielded complex [NiII(NCMe)2(OH2)(P(C6H4-2-N(CH3)2)3)] [ClO4]2 (1). Complex 1, characterized by single-crystal X-ray diffraction, SQUID, EPR, 1H NMR, IR and UV-Vis, was demonstrated to be mononuclear high-spin Ni(II) complex, containing two unpaired electrons. The geometry of the Ni center is a six-coordinate distorted octahedral complex. In addition, Ni powder and [NO][BF4] were reacted to synthesize [Ni(NCMe)6][BF4]2. Reaction of [Ni(NCMe)6][BF4]2 with an equal proportion of P(C6H4-2-N(CH3)2)3 yielded complex [NiII(NCMe)2(OH2)(P(C6H4-2-N(CH3)2)3)][BF4]2 (2). Complexes 1 or 2 reacting with the equivalent of KC8 at low temperatures under dinitrogen atmosphere, respectively, yielded complex [NiI(NCMe)2(P(C6H4-2-N(CH3)2)3)][X] (X = ClO4or BF4) (3). Complex 3 was sensitive to dioxygen and was characterized by UV-Vis and EPR spectroscopy. In the activation of small molecules, compound 3 may react with CS2 or CO2, to yield [NiIII(η2-CS2)(P(C6H4-2-N(CH3)2)3)] or [NiIII(η2-CO2)(P(C6H4-2-N(CH3)2)3)], characterized by UV-Vis and EPR. The [NiIII(η2-CS2)(P(C6H4-2-N(CH3)2)3)] reacting with KC8 in 1:1 molar ratio at low temperatures under dinitrogen atmosphere produced [NiII(η2-CS2)(P(C6H4-2-N(CH3)2)3)] (4). Complex 4, characterized by X-ray, UV-Vis, IR, 1H NMR, was low-spin Ni(II) complex.The geometry of the Ni center is a four-coordinate distorted square-planar complex.
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