(R)-3,5-Dimethyl-5,6-dihydro-pyran-2-one | 194933-34-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 英文名称: (R)-3,5-Dimethyl-5,6-dihydro-pyran-2-one
• 英文别名: (3R)-3,5-dimethyl-2,3-dihydropyran-6-one
• CAS: 194933-34-1
• 化学式: C₇H₁₀O₂
• 分子量: 126.155
• InChiKey: MAGHYAIWQFXMOY-RXMQYKEDSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.4
• 重原子数：
  9
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.57
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (R)-3,5-Dimethyl-5,6-dihydro-pyran-2-one 在 Rh/Al₂O₃ 氢气 、 二异丁基氢化铝 作用下， 以 乙醚 、 甲苯 为溶剂， 反应 11.0h， 生成 (2S,4R)-5-Hydroxy-2,4-dimethyl-pentanal
  参考文献：
  名称：

  Synthesis of Microcolin B, a Potent New Immunosuppressant Using an Efficient Mixed Imide Formation Reaction

  摘要：

  Microcolin B, a potent new immunosuppressant isolated from blue-green alga Lyngbya majuscula off the Venezuelan coast, has been made using a methyl-directed asymmetric hydrogenation reaction with rhodium on alumina catalyst on lactone 4 for the synthesis of the key (R,R)-2,4-dimethyloctanoic acid fragment 1. A new, direct mixed imide formation reaction was also developed for the production of the unusual prolylpyrrolen-2-one 2 portion of microcolin. The pentafluorophenyl ester of CBZ-proline 5 was reacted with the lithium imidate of lactam 6, providing the mixed imide in 80% yield. Coupling of acid 1 with the N-terminus of the tripeptide, followed by coupling with pyrrolylproline 2, gave microcolin B. The new mixed-imide forming reaction was also applied to a formal total synthesis of microcolin A. The pentafluorophenyl ester of TBS-protected cis-hydroxyproline was coupled with lactam 6, and the resultant imide was converted to the key pyrrolylproline made previously far microcolin A.

  DOI：

  10.1021/jo970387x
• 作为产物：
  描述：

  在 对甲苯磺酸 作用下， 以 苯 为溶剂， 反应 12.0h， 以94.7%的产率得到(R)-3,5-Dimethyl-5,6-dihydro-pyran-2-one
  参考文献：
  名称：

  Synthesis of Microcolin B, a Potent New Immunosuppressant Using an Efficient Mixed Imide Formation Reaction

  摘要：

  Microcolin B, a potent new immunosuppressant isolated from blue-green alga Lyngbya majuscula off the Venezuelan coast, has been made using a methyl-directed asymmetric hydrogenation reaction with rhodium on alumina catalyst on lactone 4 for the synthesis of the key (R,R)-2,4-dimethyloctanoic acid fragment 1. A new, direct mixed imide formation reaction was also developed for the production of the unusual prolylpyrrolen-2-one 2 portion of microcolin. The pentafluorophenyl ester of CBZ-proline 5 was reacted with the lithium imidate of lactam 6, providing the mixed imide in 80% yield. Coupling of acid 1 with the N-terminus of the tripeptide, followed by coupling with pyrrolylproline 2, gave microcolin B. The new mixed-imide forming reaction was also applied to a formal total synthesis of microcolin A. The pentafluorophenyl ester of TBS-protected cis-hydroxyproline was coupled with lactam 6, and the resultant imide was converted to the key pyrrolylproline made previously far microcolin A.

  DOI：

  10.1021/jo970387x