(2,2,6,6-tetramethylpiperidin-1-yl) (2E)-2-(3,4-dihydro-2H-pyran-6-ylmethylidene)-4-methyl-3-oxopentanoate | 878494-86-1

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 酮酸及其衍生物
• 英文名称: (2,2,6,6-tetramethylpiperidin-1-yl) (2E)-2-(3,4-dihydro-2H-pyran-6-ylmethylidene)-4-methyl-3-oxopentanoate
• CAS: 878494-86-1
• 化学式: C₂₁H₃₃NO₄
• 分子量: 363.497
• InChiKey: KUBQNNAQTADWAI-SAPNQHFASA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.7
• 重原子数：
  26
• 可旋转键数：
  6
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.71
• 拓扑面积：
  55.8
• 氢给体数：
  0
• 氢受体数：
  5

反应信息

• 作为反应物：
  描述：

  (2,2,6,6-tetramethylpiperidin-1-yl) (2E)-2-(3,4-dihydro-2H-pyran-6-ylmethylidene)-4-methyl-3-oxopentanoate 在 二异丁基氢化铝 、 对甲苯磺酸 作用下， 以 二氯甲烷 、 甲苯 为溶剂， 反应 5.25h， 生成 5-(4-Hydroxy-butyl)-2-isopropyl-furan-3-carboxylic acid 2,2,6,6-tetramethyl-piperidin-1-yl ester
  参考文献：
  名称：

  E- or Z-Selective Knoevenagel Condensation of Acetoacetic Derivatives:  Effect of Acylated Substituent, that is, TEMPO and Amines, as an Auxiliary, and New Accesses to Trisubstituted E- and Z-2-Alkenals and Furans

  摘要：

  Knoevenagel condensation of O-acetoacetylTEMPOs (2,2,6,6-tetramethylpiperidine-1-oxyl) with aldehydes substituted with an electron-withdrawing group such as aromatic and heteroaromatic ones leads preferentially to E-adducts, while acylacetoamides including Weinreb amides produce Z-adducts, exclusively. These E- and Z-adducts are selectively converted to the corresponding (2E)- and (2Z)-2hyroxyalkyl-2-alkenals, respectively, by stepwise reductions of the acyl group with DIBALH and then the carboxylic functions after protection of the hydroxy group. Transformation of the Knoevenagel products by taking advantage of the E-geometry to trisubstituted furans is also developed.

  DOI：

  10.1021/jo051952w
• 作为产物：
  描述：

  3-Hydroxy-4-methyl-pentanoic acid 2,2,6,6-tetramethyl-piperidin-1-yl ester 在 哌啶 、 草酰氯 、 二甲基亚砜 、 三乙胺 作用下， 以 乙醇 、 二氯甲烷 为溶剂， 反应 0.33h， 生成 (2,2,6,6-tetramethylpiperidin-1-yl) (2E)-2-(3,4-dihydro-2H-pyran-6-ylmethylidene)-4-methyl-3-oxopentanoate
  参考文献：
  名称：

  E- or Z-Selective Knoevenagel Condensation of Acetoacetic Derivatives:  Effect of Acylated Substituent, that is, TEMPO and Amines, as an Auxiliary, and New Accesses to Trisubstituted E- and Z-2-Alkenals and Furans

  摘要：

  Knoevenagel condensation of O-acetoacetylTEMPOs (2,2,6,6-tetramethylpiperidine-1-oxyl) with aldehydes substituted with an electron-withdrawing group such as aromatic and heteroaromatic ones leads preferentially to E-adducts, while acylacetoamides including Weinreb amides produce Z-adducts, exclusively. These E- and Z-adducts are selectively converted to the corresponding (2E)- and (2Z)-2hyroxyalkyl-2-alkenals, respectively, by stepwise reductions of the acyl group with DIBALH and then the carboxylic functions after protection of the hydroxy group. Transformation of the Knoevenagel products by taking advantage of the E-geometry to trisubstituted furans is also developed.

  DOI：

  10.1021/jo051952w

文献信息

• <i>E</i>- or <i>Z</i>-Selective Knoevenagel Condensation of Acetoacetic Derivatives:  Effect of Acylated Substituent, that is, TEMPO and Amines, as an Auxiliary, and New Accesses to Trisubstituted <i>E</i>- and <i>Z</i>-2-Alkenals and Furans
  作者：Tsutomu Inokuchi、Hiroyuki Kawafuchi

  DOI：10.1021/jo051952w

  日期：2006.2.1

  Knoevenagel condensation of O-acetoacetylTEMPOs (2,2,6,6-tetramethylpiperidine-1-oxyl) with aldehydes substituted with an electron-withdrawing group such as aromatic and heteroaromatic ones leads preferentially to E-adducts, while acylacetoamides including Weinreb amides produce Z-adducts, exclusively. These E- and Z-adducts are selectively converted to the corresponding (2E)- and (2Z)-2hyroxyalkyl-2-alkenals, respectively, by stepwise reductions of the acyl group with DIBALH and then the carboxylic functions after protection of the hydroxy group. Transformation of the Knoevenagel products by taking advantage of the E-geometry to trisubstituted furans is also developed.