(PhP(CH2SiMe2NSiMe2CH2)2PPh)Ta(C2H4)Et | 331722-45-3

• 英文名称: (PhP(CH2SiMe2NSiMe2CH2)2PPh)Ta(C2H4)Et
• CAS: 331722-45-3
• 化学式: C₂₈H₅₁N₂P₂Si₄Ta
• 分子量: 770.964
• InChiKey: JGTDYHULALFQFU-RCVPBKAYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
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• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为产物：
  描述：

  乙烯 、 (PhP(CH2SiMe2NSiMe2CH2)2PPh)TaH3(PMe3) 以 正己烷 为溶剂， 以95%的产率得到(PhP(CH2SiMe2NSiMe2CH2)2PPh)Ta(C2H4)Et
  参考文献：
  名称：

  Reaction of [P₂N₂]TaCH₂(Me) with Ethylene:  Synthesis of [P₂N₂]Ta(C₂H₄)Et, a Neutral Species with a β-Agostic Ethyl Group in Equilibrium with an α-Agostic Ethyl Group ([P₂N₂] = PhP(CH₂SiMe₂NSiMe₂CH₂)₂PPh)

  摘要：

  The photolysis of [P2N2]TaMe3 ([P2N2] = PhP(CH2SiMe2NSiMe2CH2)(2)PPh) produces [P2N2]Ta=CH2(Me) as the major product. The thermally unstable methylidene complex decomposes in solution in the absence of trapping agents to unidentified products. However, in the presence of ethylene [P2N2]Ta=CH2(Me) is slowly converted to [P2N2]Ta(C2H4)Et, with [P2N2]Ta(C2H4)Me observed as a minor product. A mechanistic study suggests that the formation of [P2N2]Ta(C2H4)Et results from the trapping of [P2N2]TaEt, formed by the migratory insertion of the methylene moiety into the tantalum-methyl bond. The minor product, [P2N2]Ta(C2H4)Me, forms from the decomposition of a tantalacyclobutane resulting from the addition of ethylene to [P2N2]Ta=CH2(Me) and is accompanied by the production of an equivalent of propylene. Pure [P2N2]Ta(C2H4)Et can be synthesized by hydrogenation of [P2N2]TaMe3 in the presence of PMe3, followed by the reaction bf ethylene with the resulting trihydride. Crystallographic and NMR data indicate the presence of a beta -agostic interaction between the ethyl group and tantalum center in [P2N2]Ta(C2H4)Et. Partially deuterated analogues of [P2N2]Ta(C2H4)Et show a large isotopic perturbation of resonance for both the beta -protons and the alpha -protons of the ethyl group, indicative of an equilibrium between a beta -agostic and an a-agostic interaction for the ethyl group in solution. An EXSY spectrum demonstrates that an additional fluxional process occurs that exchanges all of the H-1 environments of the ethyl and ethylene ligands. The mechanism of this exchange is believed to involve the direct transfer of the beta -agostic hydrogen atom from the ethyl group to the ethylene ligand, via the so-called beta -hydrogen transfer process.

  DOI：

  10.1021/ja0021621