Albuerne Isabel G, Alvarez M Angeles, García M Esther, García-Vivó Daniel, Ruiz Miguel A
Departamento de Química Orgánica e Inorgánica/IUQOEM, Universidad de Oviedo, E-33071 Oviedo, Spain.
Dalton Trans. 2017 Mar 14;46(11):3510-3525. doi: 10.1039/c7dt00132k.
The title complex reacted readily with CS and SCNPh to give the phosphinidene-cumulene adducts [MoCp{μ-κ:κ,η-P(CS)CH}(CO)(η-HMes*)(PMe)] and [MoCp{μ-κ:κ,η-P(C(NPh)S)CH}(CO)(η-HMes*)(PMe)] respectively (Mes* = 2,4,6-CHBu), as a result of the formal insertion of the C[double bond, length as m-dash]S bond of the heterocumulene into the metallocene Mo-P bond of the phosphinidene complex. The newly formed species bear a pyramidal P atom with a lone electron pair involved in fast inversion, and displayed strong nucleophilicity which enabled easy addition at the P site of carbon-based electrophiles and chalcogen atoms, while the uncoordinated S and N atoms were also competitive nucleophilic sites in these complexes. These air-sensitive materials readily added an O molecule in the solid state, to give the corresponding derivatives [MoCp{μ-κ:κ,η-OP(O)(C(X)S)CH}(CO)(η-HMes*)(PMe)] (X = S, NPh), and the CS adduct reacted selectively with S in solution to give the sulfide derivative [MoCp{μ-κ:κ,η-P(S)(CS)CH}(CO)(η-HMes*)(PMe)], which was stabilized through methylation, thus yielding the cationic complex [MoCp{μ-κ:κ,η-P(S)(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]. The CS adduct could be methylated selectively at either the P or C[double bond, length as m-dash]S sites, depending on the reagent used, to give respectively the cationic complexes [MoCp{μ-κ:κ,η-PMe(CS)CH}(CO)(η-HMes*)(PMe)] or [MoCp{μ-κ:κ,η-P(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]. Further methylation could be accomplished through reaction with [MeO]BF to give the dipositive cation [MoCp{μ-κ:κ,η-PMe(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]. In contrast, the SCNPh adduct was only methylated at the P site to yield the phosphanylthioformamidato complex [MoCp{μ-κ:κ,η-PMe(C(NPh)S)CH}(CO)(η-HMes*)(PMe)], but was readily protonated at the N site upon reaction with (NH)PF, to give the phosphanylthioformamide-like derivative [MoCp{μ-κ:κ,η-P(C(NHPh)S)CH}(CO)(η-HMes*)(PMe)]. In the presence of Na(BAr'), this adduct was even able to displace chloride from the solvent (dichloromethane) to give the corresponding chloromethyl derivative [MoCp{μ-κ:κ,η-P(CHCl)(C(NPh)S)CH}(CO)(η-HMes*)(PMe)]. The structures of the new complexes were analyzed using spectroscopic, diffractometric and, in some cases, density functional theory methods.
标题配合物与CS和SCNPh迅速反应，分别生成磷亚基-累积烯加合物[MoCp{μ-κ:κ,η-P(CS)CH}(CO)(η-HMes*)(PMe)]和[MoCp{μ-κ:κ,η-P(C(NPh)S)CH}(CO)(η-HMes*)(PMe)]（Mes* = 2,4,6-CHBu），这是由于杂累积烯的C=S键正式插入到磷亚基配合物的茂金属Mo-P键中。新形成的物种带有一个金字塔形的P原子，有一个孤电子对参与快速反转，并表现出很强的亲核性，这使得它能够在碳基亲电试剂和硫族原子的P位点容易加成，而未配位的S和N原子在这些配合物中也是有竞争力的亲核位点。这些对空气敏感的材料在固态下很容易加成一个O分子，生成相应的衍生物[MoCp{μ-κ:κ,η-OP(O)(C(X)S)CH}(CO)(η-HMes*)(PMe)]（X = S，NPh），并且CS加合物在溶液中与S选择性反应生成硫化物衍生物[MoCp{μ-κ:κ,η-P(S)(CS)CH}(CO)(η-HMes*)(PMe)]，它通过甲基化得到稳定，从而生成阳离子配合物[MoCp{μ-κ:κ,η-P(S)(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]。根据所用试剂的不同，CS加合物可以在P或C=S位点选择性地甲基化，分别生成阳离子配合物[MoCp{μ-κ:κ,η-PMe(CS)CH}(CO)(η-HMes*)(PMe)]或[MoCp{μ-κ:κ,η-P(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]。通过与[MeO]BF反应可以进一步甲基化，得到二价阳离子[MoCp{μ-κ:κ,η-PMe(C(SMe)S)CH}(CO)(η-HMes*)(PMe)]。相比之下，SCNPh加合物仅在P位点甲基化，生成膦基硫代甲酰胺基配合物[MoCp{μ-κ:κ,η-PMe(C(NPh)S)CH}(CO)(η-HMes*)(PMe)]，但与(NH)PF反应时在N位点很容易质子化，生成膦基硫代甲酰胺样衍生物[MoCp{μ-κ:κ,η-P(C(NHPh)S)CH}(CO)(η-HMes*)(PMe)]。在Na(BAr')存在下，该加合物甚至能够从溶剂（二氯甲烷）中取代氯离子，生成相应的氯甲基衍生物[MoCp{μ-κ:κ,η-P(CHCl)(C(NPh)S)CH}(CO)(η-HMes*)(PMe)]。使用光谱、衍射测量以及在某些情况下使用密度泛函理论方法对新配合物的结构进行了分析。
