Ni(CO)₃ complexes ligated by an isolable cyclic (alkyl)(amino)silylene (CAASi) or an isolable cyclic dialkylsilylene (CDASi) were synthesized by the reaction of the corresponding Ni(dvtms) complex (dvtms = 1,1,3,3‐tetramethyl‐1,3‐divinyldisiloxane) with CO to estimate the donor strengths of CAASi and CDASi. The CO stretching frequencies (Tolman electronic parameters, TEP) of the Ni(CO)₃ complexes indicate that the net donating ability of CDASi and CAASi to Ni(CO)₃ are almost the same and in between PPh₃ and P(t Bu)₃. The DFT calculations suggested that the TEP values are mainly correlated with the energy level of the lone pair orbital of the ligand but not strongly associated with those of the vacant π‐accepting orbitals.

中文翻译：

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可分离的二配位环烷基亚甲硅烷基连接的Ni（dvtms）和Ni（CO）3配合物的合成

通过相应的Ni（dvtms）络合物的反应合成了可分离的环状（烷基）（氨基）亚甲硅烷基（CAASi）或可分离的环状二烷基亚甲硅烷基（CDASi）连接的Ni（CO）₃络合物（dvtms = 1,1,3 （3-4-甲基-1,3-二乙烯基二硅氧烷）与CO来估算CAASi和CDASi的施主强度。Ni（CO）₃配合物的CO拉伸频率（Tolman电子参数，TEP）表明，CDASi和CAASi对Ni（CO）₃的净捐赠能力几乎相同，并且在PPh ₃和P（t Bu）之间₃。DFT计算表明，TEP值主要与配体的孤对轨道的能级相关，而与空的π接受轨道的能级没有强相关。