[(R,R)-(MetBuPCH2PMetBu)2Rh]BF4 | 224618-42-2

• 英文名称: [(R,R)-(MetBuPCH2PMetBu)2Rh]BF4
• CAS: 224618-42-2；328924-74-9
• 化学式: BF₄*C₂₂H₅₂P₄Rh
• 分子量: 630.26
• InChiKey: AXKZNDONNQVKNT-OCOMVUEUSA-N

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：

  [(R,R)-(MetBuPCH2PMetBu)2Rh]BF4 、 氢气 以 氘代甲醇 为溶剂， 生成
  参考文献：
  名称：

  Reaction of a Rhodium−MiniPHOS Complex with Dihydrogen:  NMR and Computational Study

  摘要：

  The rhodium-MiniPHOS complex [Rh((R,R)-(MeBuPCH2PMeBut)-P-t)(2)](+) BF4- (1) is reversibly and stereoselectively hydrogenated at low temperatures to give one isomer of cis-dihydride 2a. The second possible diastereomer, 2b, is not observed experimentally. DFT calculations suggest that 2b is 3.5 kcal mol(-1) less stable than 2a. The parameters of the equilibrium between 2a, 1, and H-2 determined by NMR are DeltaH = -7.7 +/- 0.1 kcal mol(-1) and DeltaS = -25 +/- 1 cal mol(-1) K-1. Formation of the trans-dihydride 3 is observed at around -20 degreesC. Most probably 3 is formed by isomerization of 2a or 2b. This isomerization involves reversible dissociation of the Rh-P bond. Similar dissociation of the Rh-P bond in 2a might make possible the substrate binding when 1 is used as a catalyst for asymmetric hydrogenation.

  DOI：

  10.1021/om000304u
• 作为产物：
  描述：

  di(norbornadiene)rhodium(I) tetrafluoroborate 、 (R,R)-bis(t-butylmethylphosphino)methane 以 四氢呋喃 为溶剂， 以67%的产率得到[(R,R)-(MetBuPCH2PMetBu)2Rh]BF4
  参考文献：
  名称：

  Reaction of a Rhodium−MiniPHOS Complex with Dihydrogen:  NMR and Computational Study

  摘要：

  The rhodium-MiniPHOS complex [Rh((R,R)-(MeBuPCH2PMeBut)-P-t)(2)](+) BF4- (1) is reversibly and stereoselectively hydrogenated at low temperatures to give one isomer of cis-dihydride 2a. The second possible diastereomer, 2b, is not observed experimentally. DFT calculations suggest that 2b is 3.5 kcal mol(-1) less stable than 2a. The parameters of the equilibrium between 2a, 1, and H-2 determined by NMR are DeltaH = -7.7 +/- 0.1 kcal mol(-1) and DeltaS = -25 +/- 1 cal mol(-1) K-1. Formation of the trans-dihydride 3 is observed at around -20 degreesC. Most probably 3 is formed by isomerization of 2a or 2b. This isomerization involves reversible dissociation of the Rh-P bond. Similar dissociation of the Rh-P bond in 2a might make possible the substrate binding when 1 is used as a catalyst for asymmetric hydrogenation.

  DOI：

  10.1021/om000304u
• 作为试剂：
  描述：

  2-乙酰氨基丙烯酸 在 [(R,R)-(MetBuPCH2PMetBu)2Rh]BF4 氢气 作用下， 以 甲醇 为溶剂， 20.0 ℃ 、101.33 kPa 条件下， 反应 24.0h， 以100%的产率得到N-乙酰-D-丙氨酸
  参考文献：
  名称：

  Asymmetric Hydrogenation Catalyzed by (S,S)-R-BisP*-Rh and (R,R)-R-MiniPHOS Complexes: Scope, Limitations, and Mechanism

  摘要：

  A new class of chiral C-2-symmetric bis(trialkyl)phosphine ligands has been prepared and used in Rh(I)-catalyzed asymmetric hydrogenation reactions. The Ligands, 1,2-bis(alkylmethylphosphino)ethanes 1 a-g (abbreviated as BisP*, alkyl = t-butyl, 1-adamantyl, 1-methylcyclohexyl, 1,1-diethylpropyl, cyclopentyl, cyclohexyl, isopropyl) and 1,2-bis(alkylmethylphosphino)methanes 2 a-d (abbreviated as MiniPHOS, alkyl = t-butyl, cyclohexyl, isopropyl, phenyl) are prepared by a simple synthetic approach based on the air-stable phosphine-boranes. These new ligands give the corresponding Rh(I) complexes, which are effective catalytic precursors for the asymmetric hydrogenation of a representative series of dehydroamino acids and itaconic acid derivatives. Enantioselectivities observed in these hydrogenations are universally high and in many cases exceed 99%. X-Ray characterization of four precatalysts, study of the pressure effects, deuteration experiments, and characterization of the wide series of intermediates in the catalytic cycle are used for the discussion of the possible correlation between the structure of the catalysts and the outcome of the catalytic asymmetric hydrogenation.

  DOI：

  10.1002/1615-4169(20010129)343:1<118::aid-adsc118>3.3.co;2-q