Department of Chemistry, Columbia University , New York, New York 10027, United States.
J Am Chem Soc. 2014 Jun 11;136(23):8177-80. doi: 10.1021/ja503368j. Epub 2014 May 30.
Mo(PMe3)6 cleaves the Si-H bonds of SiH4, PhSiH3, and Ph2SiH2 to afford a variety of novel silyl, hypervalent silyl, silane, and disilane complexes, as respectively illustrated by Mo(PMe3)4(SiH3)2H2, Mo(PMe3)4(κ(2)-H2-H2SiPh2H)H, Mo(PMe3)3(σ-HSiHPh2)H4, and Mo(PMe3)3(κ(2)-H2-H2Si2Ph4)H2. Mo(PMe3)4(κ(2)-H2-H2SiPh2H)H and Mo(PMe3)3(κ(2)-H2-H2Si2Ph4)H2 are respectively the first examples of complexes that feature a hypervalent κ(2)-H2-H2SiPh2H silyl ligand and a chelating disilane ligand, and both compounds convert to the diphenylsilane adduct, Mo(PMe3)3(σ-HSiHPh2)H4, in the presence of H2. Mo(PMe3)4(SiH3)2H2 undergoes isotope exchange with SiD4, and NMR spectroscopic analysis of the SiHxD4-x isotopologues released indicates that the reaction does not occur via initial reductive elimination of SiH4, but rather by a metathesis pathway.
Mo(PMe3)6 可以使 SiH4、PhSiH3 和 Ph2SiH2 的 Si-H 键断裂，生成各种新型的硅烷、高键合态硅烷、硅烷和二硅烷配合物，分别如 Mo(PMe3)4(SiH3)2H2、Mo(PMe3)4(κ(2)-H2-H2SiPh2H)H、Mo(PMe3)3(σ-HSiHPh2)H4 和 Mo(PMe3)3(κ(2)-H2-H2Si2Ph4)H2 所展示的那样。Mo(PMe3)4(κ(2)-H2-H2SiPh2H)H 和 Mo(PMe3)3(κ(2)-H2-H2Si2Ph4)H2 分别是首例具有高键合态 κ(2)-H2-H2SiPh2H 硅烷配体和螯合二硅烷配体的配合物的实例，并且这两种化合物在 H2 的存在下都转化为二苯基硅烷加合物 Mo(PMe3)3(σ-HSiHPh2)H4。Mo(PMe3)4(SiH3)2H2 可以与 SiD4 进行同位素交换，释放出的 SiHxD4-x 同位素的 NMR 光谱分析表明，反应不是通过 SiH4 的初始还原消除发生的，而是通过复分解途径发生的。
