methyl 2,6-di-O-benzyl-3,4-bis-O-(bis(3,5-dimethylphenyl)phosphino)-α-D-mannopyranoside

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl 2,6-di-O-benzyl-3,4-bis-O-(bis(3,5-dimethylphenyl)phosphino)-α-D-mannopyranoside
• 英文别名: [(2R,3R,4R,5S,6S)-4-bis(3,5-dimethylphenyl)phosphanyloxy-6-methoxy-5-phenylmethoxy-2-(phenylmethoxymethyl)oxan-3-yl]oxy-bis(3,5-dimethylphenyl)phosphane
• 化学式: C₅₃H₆₀O₆P₂
• 分子量: 855.003
• InChiKey: NOIYVKYUJQIYOC-FERWHMKMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  11.5
• 重原子数：
  61
• 可旋转键数：
  16
• 环数：
  7.0
• sp3杂化的碳原子比例：
  0.32
• 拓扑面积：
  55.4
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为产物：
  描述：

  甲基-D-丙噻 在 吡啶 、 盐酸 、 4-二甲氨基吡啶 、 sodium tetrahydroborate 、 对甲苯磺酸 作用下， 以 二氯甲烷 、 乙腈 为溶剂， 反应 16.0h， 生成 methyl 2,6-di-O-benzyl-3,4-bis-O-(bis(3,5-dimethylphenyl)phosphino)-α-D-mannopyranoside
  参考文献：
  名称：

  Carbohydrate Phosphinites as Practical Ligands in Asymmetric Catalysis:  Electronic Effects and Dependence of Backbone Chirality in Rh-Catalyzed Asymmetric Hydrogenations. Synthesis of R- or S-Amino Acids Using Natural Sugars as Ligand Precursors

  摘要：

  Vicinal diarylphosphinites derived from carbohydrates are excellent ligands for the Rh(I)-catalyzed enantioselective asymmetric hydrogenation of dehydroamino acid derivatives, producing the highest enantioselectivity of any ligands directly prepared from natural products. The enantioselectivity can be enhanced by the appropriate choice of substituents on the aromatic rings of the phosphinites. For example, the use of phosphinites with electron-donating bis(3,5-dimethylphenyl) groups on phosphorus provides ee's up to 99% for a wide range of amino acids including some with easily removable N-protecting groups. Electron-withdrawing aryl substituents, on the other hand, decrease the enantioselectivity. Sense of chiral induction in the amino acid product depends on the relative juxtaposition of the vicinal diphosphinites on a given sugar backbone. When readily available D-glucopyranosides are used as the starting sugars, 2,3-phosphinites give the S-amino acids and 3,4-phosphinites give the R-amino acids. In the case of aromatic and heteroaromatic amino acids, enantioselectivities > 95% are consistently obtained. Practical considerations such as the ease of ligand synthesis, rates of reactions, catalyst turnover, and scope and limitations in terms of substrates are discussed. A possible explanation for the enhancement of enantioselectivity by electron-rich phosphinites is offered.

  DOI：

  10.1021/jo970884d

文献信息

• Carbohydrate Phosphinites as Practical Ligands in Asymmetric Catalysis:  Electronic Effects and Dependence of Backbone Chirality in Rh-Catalyzed Asymmetric Hydrogenations. Synthesis of <i>R</i>- or <i>S</i>-Amino Acids Using Natural Sugars as Ligand Precursors
  作者：T. V. RajanBabu、Timothy A. Ayers、Gary A. Halliday、Kimberly K. You、Joseph C. Calabrese

  DOI：10.1021/jo970884d

  日期：1997.8.1

  Vicinal diarylphosphinites derived from carbohydrates are excellent ligands for the Rh(I)-catalyzed enantioselective asymmetric hydrogenation of dehydroamino acid derivatives, producing the highest enantioselectivity of any ligands directly prepared from natural products. The enantioselectivity can be enhanced by the appropriate choice of substituents on the aromatic rings of the phosphinites. For example, the use of phosphinites with electron-donating bis(3,5-dimethylphenyl) groups on phosphorus provides ee's up to 99% for a wide range of amino acids including some with easily removable N-protecting groups. Electron-withdrawing aryl substituents, on the other hand, decrease the enantioselectivity. Sense of chiral induction in the amino acid product depends on the relative juxtaposition of the vicinal diphosphinites on a given sugar backbone. When readily available D-glucopyranosides are used as the starting sugars, 2,3-phosphinites give the S-amino acids and 3,4-phosphinites give the R-amino acids. In the case of aromatic and heteroaromatic amino acids, enantioselectivities > 95% are consistently obtained. Practical considerations such as the ease of ligand synthesis, rates of reactions, catalyst turnover, and scope and limitations in terms of substrates are discussed. A possible explanation for the enhancement of enantioselectivity by electron-rich phosphinites is offered.