(2R,4S,5R)-2-chloro-3-isopropyl-4-methyl-5-phenyl-1,3,2-oxazaphospholidin-2-one | 198906-15-9

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: (2R,4S,5R)-2-chloro-3-isopropyl-4-methyl-5-phenyl-1,3,2-oxazaphospholidin-2-one
• 英文别名: (2R,4S,5R)-2-Chloro-4-methyl-3-(1'-methylethyl)-5-phenyl-1,3,2-oxazaphospholidin-2-one
• CAS: 198906-15-9
• 化学式: C₁₂H₁₇ClNO₂P
• 分子量: 273.699
• InChiKey: JADKECUEBJIHRA-ZMNCSTGQSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.2
• 重原子数：
  17.0
• 可旋转键数：
  2.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  29.54
• 氢给体数：
  0.0
• 氢受体数：
  2.0

反应信息

• 作为反应物：
  描述：

  (2R,4S,5R)-2-chloro-3-isopropyl-4-methyl-5-phenyl-1,3,2-oxazaphospholidin-2-one 在 三乙胺 作用下， 以 二氯甲烷 为溶剂， 生成 (2S,2'S,2''S,4S,4'S,4''S,5R,5'R,5''R)-N,N',N''-tris[2-(3,4-dimethyl-2-oxo-5-phenyl-1,3,2-oxazaphospholan-2-yl)aminoethyl]amine
  参考文献：
  名称：

  Preparation of Chiral Phosphorus(V) Reagents and Their Uses with Borane in the Enantioselective Reduction of Ketones

  摘要：

  AbstractChiral pentavalent phosphorus reagents 5–17 were prepared from POCl3 and ephedrine (or the related α‐amino alcohols), followed by substitution with nucleophiles of phenylmagnesium bromide, alcohols, amines, diamines and triamines. The substitution reactions occurred in a stereospecific manner with retention of the configuration at the phosphorus center. The structures of these phosphorus(V) reagents were determined by spectral methods and verified by X‐ray diffraction in several instances. These phosphorus(V) reagents were used with borane/dimethylsulfide complex in the enantioselective reduction of aromatic, aliphatic and heterocyclic ketones. The phosphorus(V) reagents likely functioned as Lewis bases to react with borane, forming in situ zwitterionic species as the chiral reducing agents. The reactions were generally carried out at 0 °C in tetrahydrofuran solution with a molar ratio of ketone/borane/phosphoramidate = 1:1:0.2 to afford secondary alcohols with modest enantioselectivity, up to 67% ee in the reduction of 4′‐methylacetophenone.

  DOI：

  10.1002/jccs.199900108
• 作为产物：
  描述：

  去甲麻黄碱 在 lithium aluminium tetrahydride 、 对甲苯磺酸 、 三乙胺 、 三氯氧磷 作用下， 以 四氢呋喃 、 丙酮 为溶剂， 反应 14.0h， 生成 (2R,4S,5R)-2-chloro-3-isopropyl-4-methyl-5-phenyl-1,3,2-oxazaphospholidin-2-one
  参考文献：
  名称：

  Preparation of Chiral Phosphorus(V) Reagents and Their Uses with Borane in the Enantioselective Reduction of Ketones

  摘要：

  AbstractChiral pentavalent phosphorus reagents 5–17 were prepared from POCl3 and ephedrine (or the related α‐amino alcohols), followed by substitution with nucleophiles of phenylmagnesium bromide, alcohols, amines, diamines and triamines. The substitution reactions occurred in a stereospecific manner with retention of the configuration at the phosphorus center. The structures of these phosphorus(V) reagents were determined by spectral methods and verified by X‐ray diffraction in several instances. These phosphorus(V) reagents were used with borane/dimethylsulfide complex in the enantioselective reduction of aromatic, aliphatic and heterocyclic ketones. The phosphorus(V) reagents likely functioned as Lewis bases to react with borane, forming in situ zwitterionic species as the chiral reducing agents. The reactions were generally carried out at 0 °C in tetrahydrofuran solution with a molar ratio of ketone/borane/phosphoramidate = 1:1:0.2 to afford secondary alcohols with modest enantioselectivity, up to 67% ee in the reduction of 4′‐methylacetophenone.

  DOI：

  10.1002/jccs.199900108

文献信息

• Stereoselective Umpolung Reactions with MetalatedP-Chiral Cyanohydrin Phosphates—Enantioselective Synthesis of Tertiary Cyanohydrins
  作者：Thomas Schrader

  DOI：10.1002/chem.19970030815

  日期：1997.8

  AbstractWe present the first cyanohydrin derivative4that allows diastereoselective umpolung reactions. In4the OH group of the cyanohydrin is linked with a chiral phosphate, which can be removed hydrolytically after asymmetric synthesis. Cyclization of pseudoephedrine1dwith POCl3gave2d. This was followed by addition of racemic benzaldehyde cyanohydrin3to give the key intermediate4dwith complete retention of the configuration at phosphorus. Deprotonation of4d, followed by addition of a wide variety of electrophiles afforded the crystalline products5with high diastereomeric excesses (deup to 94%). High asymmetric induction was also achieved for the reaction of4−Li+with acyl halides, α‐bromoacetates, 2‐cycloalkenones, α,β‐unsaturated esters, and γ‐bromoacetates. Lewis acid assisted hydrolysis proceeded without racemization and gave high yields of ketone cyanohydrins6. From the ring‐opened chiral auxiliary7, optically pure pseudoephedrine1was readily recovered by acid hydrolysis. Optically pure (R) and (S) ketone cyanohydrins are now accessible in a very general strategy, which circumvents the substrate limitations of enzymatic synthesis.