WCl2(CH2=CH2)2(PMePh2)2 | 90245-67-3

• 英文名称: WCl2(CH2=CH2)2(PMePh2)2
• CAS: 90245-67-3
• 化学式: C₃₀H₃₄Cl₂P₂W
• 分子量: 711.303
• InChiKey: NSBBWGPDLYZNNT-UHFFFAOYSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 重原子数：
  None
• 可旋转键数：
  None
• 环数：
  None
• sp3杂化的碳原子比例：
  None
• 拓扑面积：
  None
• 氢给体数：
  None
• 氢受体数：
  None

反应信息

• 作为反应物：
  描述：

  WCl2(CH2=CH2)2(PMePh2)2 在 epoxides 作用下， 以 not given 为溶剂， 生成 W(O)Cl2(PMePh2)2(ethylene)
  参考文献：
  名称：

  On the mechanism of oxygen-atom or nitrene-group transfer in reactions of epoxides and aziridines with tungsten(II) compounds

  摘要：

  The tungsten(II) complexes WCl2(PMePh2)4 (1) and WCl2(CH2=CH2)2(PMePh2)2 (2) react with epoxides and aziridines to form tungsten(IV)-oxo and -imido complexes. The relative reactivities of epoxides with 2 have been determined from competition experiments. More substituted epoxides are harder to deoxygenate: the reactivities of ethylene, isobutylene, and tetramethylethylene oxides fall in the geometric progression 100:10:1. cis-2-Butene oxide is deoxygenated faster than its trans isomer. Reaction occurs with predominant (greater-than-or-equal-to 85%) retention of configuration (e.g. cis epoxides to cis olefins). The reaction of 2 with ethylene-d4 oxide yields W(O)Cl2(CH2=CH2)(PMePh2)2 (4) and uncoordinated CD2=CD2. The data suggest that de-epoxidation occurs via oxygen atom abstraction, and not via an oxametallacyclobutane which rearranges to an oxo-ethylene complex. Similarly, the tungsten center is suggested to attack the nitrogen atom of the aziridines, rather than react by initial oxidative addition of a C-N bond. This is indicated by the observation of an N-bound complex of aziridine and by the much slower rates of reaction for aziridines with bulky substituents on the nitrogen. The reactivities of para-substituted styrene epoxides are not strongly affected by the nature of the substituent (a-rho+-value of -0.5 is calculated with Hammett sigma+ parameters) indicating that the transition state is not very polar, although there appears to be some conjugation between the phenyl ring' and the epoxide. In sum, the data are most consistent with either concerted oxygen or nitrene transfer to tungsten or a mechanism involving a short-lived radical intermediate.

  DOI：

  10.1021/ja00003a021
• 作为产物：
  描述：

  乙烯 、 二苯基甲氧基膦 、 W^IICl2(PMePh2)4 以 苯 为溶剂， 生成 WCl2(CH2=CH2)2(PMePh2)2
  参考文献：
  名称：

  WCl 2 L 4（L ＝膦）的反应。1.一类新型的钨（II）乙烯络合物

  摘要：

  DOI：

  10.1021/om00086a013
• 作为试剂：
  描述：

  2,3-cis-epoxybutane 在 WCl2(CH2=CH2)2(PMePh2)2 作用下， 以 氘代苯 为溶剂， 生成 2-丁烯
  参考文献：
  名称：

  On the mechanism of oxygen-atom or nitrene-group transfer in reactions of epoxides and aziridines with tungsten(II) compounds

  摘要：

  The tungsten(II) complexes WCl2(PMePh2)4 (1) and WCl2(CH2=CH2)2(PMePh2)2 (2) react with epoxides and aziridines to form tungsten(IV)-oxo and -imido complexes. The relative reactivities of epoxides with 2 have been determined from competition experiments. More substituted epoxides are harder to deoxygenate: the reactivities of ethylene, isobutylene, and tetramethylethylene oxides fall in the geometric progression 100:10:1. cis-2-Butene oxide is deoxygenated faster than its trans isomer. Reaction occurs with predominant (greater-than-or-equal-to 85%) retention of configuration (e.g. cis epoxides to cis olefins). The reaction of 2 with ethylene-d4 oxide yields W(O)Cl2(CH2=CH2)(PMePh2)2 (4) and uncoordinated CD2=CD2. The data suggest that de-epoxidation occurs via oxygen atom abstraction, and not via an oxametallacyclobutane which rearranges to an oxo-ethylene complex. Similarly, the tungsten center is suggested to attack the nitrogen atom of the aziridines, rather than react by initial oxidative addition of a C-N bond. This is indicated by the observation of an N-bound complex of aziridine and by the much slower rates of reaction for aziridines with bulky substituents on the nitrogen. The reactivities of para-substituted styrene epoxides are not strongly affected by the nature of the substituent (a-rho+-value of -0.5 is calculated with Hammett sigma+ parameters) indicating that the transition state is not very polar, although there appears to be some conjugation between the phenyl ring' and the epoxide. In sum, the data are most consistent with either concerted oxygen or nitrene transfer to tungsten or a mechanism involving a short-lived radical intermediate.

  DOI：

  10.1021/ja00003a021

文献信息

• Deoxygenative coupling of ketones and alkenes by tungsten(II) compounds
  作者：Jeffrey C. Bryan、Jeffrey B. Arterburn、Gerald K. Cook、James M. Mayer

  DOI：10.1021/om00060a010

  日期：1992.12

  Tungsten(II) compounds such as WCl2(PMePh2)4 (1) react with acetone and ethylene tro give a good yield of the tungsten(IV)-oxo complexes W(O)(CH2=CH2)Cl2(PMePh2)2 (4) and a moderate amount of 3-methyl-1-butene. Cyclopentanone and ethylene plus 1 yield 4 and vinylcyclopentane; methyl vinyl ketone and ethylene give 4 and 3-methyl- 1,4-pentadiene. The react ion of cyclopentanone and propylene with 1 yields a small amount of 2-cyclopentylpropene. Intramolecular deoxygenative coupling occurs with 6- and 7-en-2-ones to form 1-methyl-2-methylene-substituted cyclopentyl and cyclohexyl ring systems, respectively. The net result of these reactions is transfer of the ketone oxygen atom to tungsten, accompanied with its replacement by a hydrogen and a vinyl group. The suggested mechanism for this deoxygenative coupling (Scheme I) is coordination of both the ketone and ethylene to tungsten, coupling to form a 2-oxametal-lacyclopentane, beta-hydrogen elimination to an allyloxy hydride species, C-0 bond cleavage to an oxo allyl hydride complex, and reductive elimination of alkene. Consistent with the suggestion of an oxametallacycle, hydrolysis of the reaction mixture of 1 and 6-hepten-2-one provides stereospecifically trans-1,2-di-methylcyclopentanol. The enones methyl vinyl ketone and 5-hexen-2-one react with 1 to form stable complexes in which the enone is bound in an eta4 fashion, similar to the proposed mixed alkene ketone intermediates in the coupling reactions. A related tungsten(II) butadiene complex, WCl2(CH2=CHCH=CH2)(PMePhl)2, has also been isolated.