(4,4',5,5'-tetramethyl-2,2'-biphosphinine)tetracarbonylmolybdenum | 141397-76-4

• 英文名称: (4,4',5,5'-tetramethyl-2,2'-biphosphinine)tetracarbonylmolybdenum
• CAS: 141397-76-4
• 化学式: C₁₈H₁₆MoO₄P₂
• 分子量: 454.21
• InChiKey: MXWJKXAPDGOUDO-UHFFFAOYSA-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：

  cis-bis(4,5-dimethyl-2-bromophosphinine)tetracarbonylmolybdenum 在 C₆H₅Li 、 NiBr₂(1,2-dimethoxyethane) 作用下， 以 四氢呋喃 、 乙醚 、 环己烷 为溶剂， 以30%的产率得到(4,4',5,5'-tetramethyl-2,2'-biphosphinine)tetracarbonylmolybdenum
  参考文献：
  名称：

  Structural and electrochemical study of a 2,2'-biphosphinine

  摘要：

  An improved synthesis of 4,4,5,5'-tetramethyl-2,2-biphosphinine from 2-bromo-4,5-dimethlylphosphinine using (Ph3P)2CoCl2 as the coupling reagent is described. The coupling can also be effected in the coordination sphere of molybdenum tetracarbonyl via a bromine to lithium exchange followed by C-C bond formation with (DME)NiBr2. The recovery of the free 2,2'-biphosphinine from the Mo(CO)4 chelate thus obtained appears to be difficult. The X-ray crystal structure analysis of the 2,2'-biphosphinine at -100-degrees-C suggests that the interaction between the two rings and the rotation barrier around the C-C bridge are weak. The complexation with Cr(CO)4 does not alter the geometry of the biphosphinine, and no electronic delocalization seems to be operative within the five-membered metallacycle. The electrochemical reduction of the tetramethylbiphosphinine is easier than that of 4,4'-dimethyl-2,2'-bipyridine. The first monoelectronic wave occurs at -1.85(2) V vs SCE in DMF for the phosphorus ligand as compared to -2.20(1) V vs SCE for the nitrogen ligand. As a consequence, the 2,2'-biphosphinine is a better ligand for electron-rich metals and is able to displace 2,2'-bipyridine from its Cr(CO)4 chelate.

  DOI：

  10.1021/om00043a032