4-O-acetyl-3-O-allyl-6-tert-butyldiphenylsiloxy-β-D-methylmannopyranoside | 872352-58-4

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 4-O-acetyl-3-O-allyl-6-tert-butyldiphenylsiloxy-β-D-methylmannopyranoside
• CAS: 872352-58-4
• 化学式: C₂₈H₃₈O₇Si
• 分子量: 514.691
• InChiKey: XUGGEPUUHTXGMY-NTYGKXENSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.8
• 重原子数：
  36.0
• 可旋转键数：
  10.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.46
• 拓扑面积：
  83.45
• 氢给体数：
  1.0
• 氢受体数：
  7.0

反应信息

• 作为反应物：
  描述：

  4-O-acetyl-3-O-allyl-6-tert-butyldiphenylsiloxy-β-D-methylmannopyranoside 在 乙酸酐 、 pyridinium chlorochromate 作用下， 以 二氯甲烷 为溶剂， 反应 16.0h， 以66%的产率得到Acetic acid (2R,3R,4S,6S)-4-allyloxy-2-(tert-butyl-diphenyl-silanyloxymethyl)-6-methoxy-5-oxo-tetrahydro-pyran-3-yl ester
  参考文献：
  名称：

  1-Bromo-1-lithioethene:  A Practical Reagent in Organic Synthesis

  摘要：

  A reliable preparative scale synthesis of 1-bromo-1-lithioethene is reported. This reagent undergoes clean 1,2-addition with a range of aldehydes and ketones at -110 degrees C to afford the corresponding 2-bromo-1-alken-3-ols in moderate to excellent yield. Trapping with other electrophiles (acylsilanes, chlorosilanes, tributyltin chloride, iodine) cleanly provides practically useful yields of various 1-substituted 1-bromoethene products. Unexpectedly high diastereoselectivities were observed during the addition of 1-bromo-1-lithioethene to alpha-siloxy aldehydes (typically 10:1, Felkin-Ahn control) and protected ketopyranose and ketofuranose sugars (>= 10:1, addition from the less-hindered face). The title organolithium reagent possesses relatively low basicity at low temperature, and is compatible with a variety of common protecting groups. We believe that these unusual properties of 1-bronio-1-lithioethene may originate from the specific crystalline structure of the reagent in which lithium is coordinatively saturated and thus unavailable for chelation.

  DOI：

  10.1021/jo051125v
• 作为产物：
  描述：

  methyl 6-O-tert-butyldiphenylsilyl-α-D-mannopyranoside 在 4-二甲氨基吡啶 、 二正丁基氧化锡 作用下， 以 二氯甲烷 、 甲苯 为溶剂， 反应 136.0h， 生成 4-O-acetyl-3-O-allyl-6-tert-butyldiphenylsiloxy-β-D-methylmannopyranoside
  参考文献：
  名称：

  1-Bromo-1-lithioethene:  A Practical Reagent in Organic Synthesis

  摘要：

  A reliable preparative scale synthesis of 1-bromo-1-lithioethene is reported. This reagent undergoes clean 1,2-addition with a range of aldehydes and ketones at -110 degrees C to afford the corresponding 2-bromo-1-alken-3-ols in moderate to excellent yield. Trapping with other electrophiles (acylsilanes, chlorosilanes, tributyltin chloride, iodine) cleanly provides practically useful yields of various 1-substituted 1-bromoethene products. Unexpectedly high diastereoselectivities were observed during the addition of 1-bromo-1-lithioethene to alpha-siloxy aldehydes (typically 10:1, Felkin-Ahn control) and protected ketopyranose and ketofuranose sugars (>= 10:1, addition from the less-hindered face). The title organolithium reagent possesses relatively low basicity at low temperature, and is compatible with a variety of common protecting groups. We believe that these unusual properties of 1-bronio-1-lithioethene may originate from the specific crystalline structure of the reagent in which lithium is coordinatively saturated and thus unavailable for chelation.

  DOI：

  10.1021/jo051125v