Four new dithiocarbamatonickel(II) complexes [Ni(dchdtc)(NCS)(PPh3)] (1), [Ni(dchdtc)(CN)(PPh3)] (2), [Ni(dchdtc)(PPh3)2]ClO4 (3), and [Ni(dchdtc)(dppe)]ClO4 (4) (dchdtc = N,N-dicyclohexyldithiocarbamate anion, PPh3 = triphenylphosphine, and dppe = 1,2-bis(diphenylphosphino)ethane) were prepared from the parent [Ni(dchdtc)2]. All four complexes were analyzed by CV, UV–vis, IR, and NMR (1H, 13C, and 31P) spectra. 13C NMR spectra of the complexes (1–4) show the most notable >13CS2 signals at around 200 ppm. In the cyclohexyl ring, the α-CH carbon is deshielded to a greater extent on complexation. Extraordinary deshielding was observed for the 31P signal in all of the cases, indicating the effective bonding of phosphorus to the metal center. Single crystal X-ray structural analysis of the mixed ligand complexes (1–3) indicates a decrease in S–Ni–S bite angle when compared to that of the parent bis(dithiocarbamate), due to an increase in steric crowding around the central metal by the introduction of a bulky PPh3. The trans effects on Ni–S bonds can be arranged in the following order: NCS− < PPh3 < CN−. The S23, (1.306(3) Å), because of the steric effect exerted by two PPh3 groups and dchdtc. The observed negative reduction potentials follow the order: 1 > 2 > 3, indicating the presence of a higher relative electron density on 1 compared to 2 and 3.< bond is very short for complex
四种新的二
硫代
氨基甲
镍(II)配合物 [Ni(dchdtc)(
NCS)(PPh3)] (1)、[Ni(dchdtc)(CN)(PPh3)] (2)、[Ni(dchdtc)(PPh3)2]ClO4 (3) 和 [Ni(dchdtc)(dppe)]ClO4 (4)(dchdtc = N,N-二环己基二
硫代
氨基甲酸根阴离子,PPh3 =
三苯基膦,dppe = 1,2-双(
二苯基膦)
乙烷)由母体制备[Ni(dchdtc)2]。所有四种配合物均通过 CV、UV-vis、IR 和 NMR(1H、13C 和 31P)光谱进行分析。配合物 (1–4) 的 13C NMR 谱显示在 200 ppm 左右最显着的 >13CS2 信号。在环己基环中,α-CH碳在络合时更大程度地脱屏蔽。在所有情况下都观察到 31P 信号的异常去屏蔽,表明
磷与
金属中心的有效键合。混合
配体配合物 (1-3) 的单晶 X 射线结构分析表明,与母体双(二
硫代
氨基甲酸酯)相比,S-Ni-S 咬角减小,这是由于中心周围空间拥挤的增加。通过引入大体积的 PPh3 来形成
金属。 Ni-S 键的反式效应可以按以下顺序排列:
NCS− < PPh3 < CN−。 S23 (1.306(3) Å),由于两个 PPh3 基团和 dchdtc 产生的空间效应。观察到的负还原电位遵循以下顺序:1 > 2 > 3,表明与 2 和 3 相比,1 上存在更高的相对电子密度。< 键对于配合物来说非常短