Silylene Hydride Complexes of Molybdenum with Silicon−Hydrogen Interactions: Neutron Structure of (η5-C5Me5)(Me2PCH2CH2PMe2)Mo(H)(SiEt2)
Silylene Hydride Complexes of Molybdenum with Silicon−Hydrogen Interactions: Neutron Structure of (η5-C5Me5)(Me2PCH2CH2PMe2)Mo(H)(SiEt2)
复制标题
具有硅氢相互作用的钼氢化硅络合物：(η5-C5Me5)(Me2PCH2CH2PMe2)Mo(H)(SiEt2)的中子结构
DOI：
10.1021/ja040026g
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发表时间：
2004
影响因子：
15
通讯作者：
J. A. Cowan
中科院分区：
文献类型：
--
作者：
B. Mork;T. Tilley;A. Schultz;J. A. Cowan
在1当量dmpe和1当量三甲基膦存在下，用3.1当量Na/Hg汞齐（1.0%w/w）还原Cp* MoCl 4，得到氯化钼配合物Cp*（dmpe）（PMe 3）MoCl（1）（Cp* = 1，2，3，4，5-五甲基膦，dmpe = 1，2-双（二甲基膦基）乙烷）。1与PhCH_2 MgCl的烷基化反应高产率地释放出PMe_3，得到18电子π-苄基配合物Cp_*（dmpe）Mo（η_3-CH_2 Ph）（2）。变温NMR实验证明2与其16电子η1-苄基异构体[Cp*（dmpe）Mo（η1-CH 2 Ph）]处于平衡状态。2与CO反应生成羰基苄基配合物Cp*（dmpe）（CO）Mo（η1-CH 2 Ph）（3）进一步支持了这一点。发现配合物2与二取代硅烷H_2SiRR ′（RR ′ = Me_2，Et_2，MePh和Ph_2）反应生成甲苯和亚甲硅烷基配合物Cp ~*（dmpe）Mo（H）（SiRR ′）（4a：RR ′ = Me_2，4 b：RR ′ = Et_2，4c：RR ′ = MePh，4d：RR ′ = Ph_2）. 2与单取代硅烷H3 SiR（R = Ph，Mes，Mes = 2，4，6-三甲基苯基）反应生成2，3，4-三甲基-1，4-二氢-1，4-二氢
Reduction of Cp*MoCl4 with 3.1 equiv of Na/Hg amalgam (1.0% w/w) in the presence of 1 equiv of dmpe and 1 equiv of trimethylphosphine afforded the molybdenum(II) chloride complex Cp*(dmpe)(PMe3)MoCl (1) (Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl, dmpe = 1,2-bis(dimethylphosphino)ethane). Alkylation of 1 with PhCH2MgCl proceeded in high yield to liberate PMe3 and give the 18-electron π-benzyl complex Cp*(dmpe)Mo(η3-CH2Ph) (2). Variable temperature NMR experiments provided evidence that 2 is in equilibrium with its 16-electron η1-benzyl isomer [Cp*(dmpe)Mo(η1-CH2Ph)]. This was further supported by reaction of 2 with CO to yield the carbonyl benzyl complex Cp*(dmpe)(CO)Mo(η1-CH2Ph) (3). Complex 2 was found to react with disubstituted silanes H2SiRR' (RR' = Me2, Et2, MePh, and Ph2) to form toluene and the silylene complexes Cp*(dmpe)Mo(H)(SiRR') (4a: RR' = Me2; 4b: RR' = Et2; 4c: RR' = MePh; 4d: RR' = Ph2). Reactions of 2 with monosubstituted silanes H3SiR (R = Ph, Mes, Mes = 2,4,6-trimethylphenyl) prod...