2,5-cis-5,6-cis-6(R)-carbomethoxy-5,6-dihydro-2-methoxy-5-methyl-2H-pyran | 133885-25-3

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 英文名称: 2,5-cis-5,6-cis-6(R)-carbomethoxy-5,6-dihydro-2-methoxy-5-methyl-2H-pyran
• 英文别名: methyl (2R,3S,6S)-6-methoxy-3-methyl-3,6-dihydro-2H-pyran-2-carboxylate
• CAS: 133885-25-3
• 化学式: C₉H₁₄O₄
• 分子量: 186.208
• InChiKey: OXVJHRAXTRGEBP-BIIVOSGPSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.72
• 重原子数：
  13.0
• 可旋转键数：
  2.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  44.76
• 氢给体数：
  0.0
• 氢受体数：
  4.0

反应信息

• 作为产物：
  描述：

  乙醛酸甲酯 、 1,3-Pentadiene, 1-methoxy-, (E,Z)- 在 二异丙氧基二氯化钛 、 (R)-1,1'-Bi-2-naphthol 作用下， 以 二氯甲烷 为溶剂， 反应 1.0h， 生成 2,5-cis-5,6-cis-6(S)-carbomethyxy-5,6-dihydro-2-methoxy-5-methyl-2H-pyran 、 2,5-cis-5,6-cis-6(R)-carbomethoxy-5,6-dihydro-2-methoxy-5-methyl-2H-pyran
  参考文献：
  名称：

  Asymmetric Catalysis of Diels-Alder Cycloadditions by an MS-Free Binaphthol-Titanium Complex: Dramatic Effect of MS, Linear vs Positive Nonlinear Relationship, and Synthetic Applications

  摘要：

  Asymmetric Diels-Alder (D.-A.) reaction of 5-hydroxynaphthoquinone (juglone) with butadienyl acetate catalyzed by the binaphthol-derived chiral titanium (BINOL-Ti) complex 1 proceeds in only 9% ee in the presence of molecular sieves (MS). Remarkably, however, this reaction proceeds in 76-96% ee with BINOL-Ti complex 1 freed from MS to provide the endo-adducts useful for the synthesis of anthracyclines and tetracyclines. The solid MS-free BINOL-Ti complex 1 is stable for months at -20 degrees C, Enhancements in endo selectivity and asymmetric induction are observed with the MS-free BINOL-Ti 1 also in the catalyzed D.-A. cycloaddition of methacrolein and glyoxylate with 1,3-dienol ethers and esters. The glyoxylate adducts can be converted to the mevinolin (compactin) intermediates. Surprisingly, the MS-free complex 1 exhibits not only a linear relationship between the ee's of BINOL-Ti 1 and the D.-A. products but also a positive nonlinear effect (asymmetric amplification), depending simply on the mixing manner of (R)-1 with (S)-1 or (+/-)-1.

  DOI：

  10.1021/ja00086a014

文献信息

• Enantioselective Hetero-Diels-Alder reaction with glyoxylate catalyzed by chiral titanium complex: asymmetric synthesis of the lactone portion of mevinolin and compactin
  作者：Masahiro Terada、Koichi Mikami、Takeshi Nakai

  DOI：10.1016/s0040-4039(00)92124-5

  日期：1991.2

  Asymmetric Diels-Alder reaction with methyl glyoxylate catalyzed by the chiral titanium complex 1 provides the dihydropyran carboxylate in high enantiomeric purity, which can be converted to the lactone portion of mevinolin or compactin.

  通过手性钛络合物1催化的乙醛酸甲酯与不对称Diels-Alder反应提供了高对映体纯度的二氢吡喃羧酸盐，其可以转化为美维林或紧密蛋白的内酯部分。