methoxyethyl 2-O-benzyl-3,4-di-O-TIPS-β-L-rhamnopyranoside | 1382229-75-5

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methoxyethyl 2-O-benzyl-3,4-di-O-TIPS-β-L-rhamnopyranoside
• CAS: 1382229-75-5
• 化学式: C₃₄H₆₄O₆Si₂
• 分子量: 625.05
• InChiKey: UCNWESJVSLHWDF-AMHCVULOSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  9.1
• 重原子数：
  42.0
• 可旋转键数：
  17.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.82
• 拓扑面积：
  55.38
• 氢给体数：
  0.0
• 氢受体数：
  6.0

反应信息

• 作为产物：
  描述：

  (4aS,5S,7S,8R,8aR)-2,3-dimethoxy-2,3,5-trimethyl-8-phenylmethoxy-7-phenylsulfanyl-5,7,8,8a-tetrahydro-4aH-pyrano[3,4-b][1,4]dioxine 在 2,6-二甲基吡啶 、 水 、 三氟乙酸 作用下， 以 二氯甲烷 为溶剂， 反应 1.0h， 生成 methoxyethyl 2-O-benzyl-3,4-di-O-TIPS-α-L-rhamnopyranoside 、 methoxyethyl 2-O-benzyl-3,4-di-O-TIPS-β-L-rhamnopyranoside
  参考文献：
  名称：

  Rhamnosylation: Diastereoselectivity of Conformationally Armed Donors

  摘要：

  The alpha/beta-selectivity of super-armed rhamnosyl donors have been investigated in glycosylation reactions. The solvent was found to have a minor influence, whereas temperature was crucial for the diastereoselectivity. At very low temperature, a modest beta-selectivity could be obtained, and increasing temperature gave excellent a-selectivity. The donors were highly reactive, and activation was observed at temperatures as low as -107 degrees C. Different promoter systems and leaving groups were investigated, and only activation with a heterogeneous catalyst increased the amount of the beta-anomer significantly. By introducing an electron-withdrawing nonparticipating group, benzyl sulfonyl, on 2-O, an increase in beta-product was observed.

  DOI：

  10.1021/jo300591k