2-methyl-6,7-dihydrocyclopenta[b]pyran-4(5H)-one | 101234-57-5

• 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-methyl-6,7-dihydrocyclopenta[b]pyran-4(5H)-one
• 英文别名: 2,3-Cyclopenteno-6-methyl-4-pyron；2-Methyl-5.6-trimethylen-pyron-(4)；2-methyl-6,7-dihydro-5H-cyclopenta[b]pyran-4-one；2-methyl-6,7-dihydro-5H-cyclopenta[b]pyran-4-one
• CAS: 101234-57-5
• 化学式: C₉H₁₀O₂
• 分子量: 150.177
• InChiKey: BYGXMWCQVIKJGM-UHFFFAOYSA-N

物化性质

• 熔点：
  120-121 °C
• 沸点：
  302.1±11.0 °C(Predicted)
• 密度：
  1.15±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  1.2
• 重原子数：
  11
• 可旋转键数：
  0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.44
• 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：

  2-methyl-6,7-dihydrocyclopenta[b]pyran-4(5H)-one 、 甲胺 生成 1,2-dimethyl-6,7-dihydro-5H-cyclopenta[b]pyridin-4-one
  参考文献：
  名称：

  KATANO, KIYOAKI;OGINO, HIROKO;IWAMATSU, KATSUYOSHI;NAKABAYASHI, SATORU;YO+, J. ANTIBIOTICS, 43,(1990) N, C. 1150-1159

  摘要：

  DOI：
• 作为产物：
  描述：

  2-甲氧基丙烯 、 2-diazocyclohexane-1,3-dione 在 三苯基膦氯金 作用下， 以 对二甲苯 为溶剂， 反应 12.0h， 以80%的产率得到2-methyl-6,7-dihydrocyclopenta[b]pyran-4(5H)-one
  参考文献：
  名称：

  金催化Wolff重排/ [4 + 2]环加成/消除反应的级联反应一锅合成多取代的4-吡喃酮

  摘要：

  AbstractAn efficient one‐pot method is described for the synthesis of a variety of di‐ and trisubstituted 4‐pyrones based on the gold‐catalyzed cascade reactions between cyclic or acyclic diazodicarbonyl compounds and vinyl ethers. The key strategy used involves the gold‐catalyzed Wolff rearrangement of diazo compounds followed by [4+2] cycloaddition and elimination. This methodology is also applied to the synthesis of tetrasubstituted 4‐pyrones.magnified image

  DOI：

  10.1002/adsc.201301086

文献信息

• Photochemical ring-contraction of fused bicyclic 4-pyrones: A novel 2-step cyclopentannulation approach
  作者：F.G. West、P.V. Fisher、G.U. Gunawardena、Scott Mitchell

  DOI：10.1016/s0040-4039(00)60630-5

  日期：1993.9

  Fused bicyclic 4-pyrones were prepared by condensation of enamines derived from cyclic ketones with diketene or substituted 1,3-dioxin-4-ones. Photolysis in a hydroxylic medium led to bicyclo[n3.0]alkenones bearing oxygenation at both angular positions. This process is occurs via regioselective nucleophilic solvent attack on the intermediate tricyclic oxyallyl zwitterion. The efficiency of the transformation

  稠合的双环4-吡喃酮是通过将环酮衍生的烯胺与双烯酮或取代的1,3-二恶英-4-酮缩合而制备的。在羟基介质中的光解导致双环[n3.0]烯酮在两个角位置均带有氧合。该过程是通过区域选择性亲核溶剂攻击中间的三环氧基烯丙基两性离子而发生的。发现转化效率取决于与4-吡喃酮稠合的环的大小。
• Normal, Abnormal, and Cascade Wittig Olefinations of α-Oxoketenes
  作者：David Pierrot、Marc Presset、Jean Rodriguez、Damien Bonne、Yoann Coquerel

  DOI：10.1002/chem.201801533

  日期：2018.8.1

  α‐Oxoketenes generated in situ by a thermal Wolff rearrangement have been found to participate as 1,2‐ and 1,4‐ambident C‐electrophilic/O‐nucleophilic reagents towards donor/acceptor carbonyl‐stabilized Wittig ylides. This resulted in the very direct and practical syntheses of functionalized allenes by a normal Wittig olefination, 4H‐pyran‐4‐ones by an abnormal Wittig olefination, or 4H‐pyranylidenes following

  通过热重排沃尔夫原位产生α-Oxoketenes已发现参与如1,2-和1,4-两可Ç -electrophilic / ö朝供体/受体羰基稳定化的维悌希叶立德-nucleophilic试剂。通过正常的Wittig烯化，4 H-吡喃-4-酮，异常的Wittig烯化或4 H合成功能化的烯类化合物，可实现非常直接和实用的合成。Wittig /异常Wittig级联序列后的吡喃基亚基作为所用底物组合的函数。机械实验和计算研究为这些反应性开关提供了完全合理的依据。该系列中鉴定了无路易斯酸的Wittig烯烃的一些不寻常的机械特征，例如甜菜碱中间体的参与和正常Wittig烯烃的一定程度的可逆性。异常Wittig烯烃完全被发现。
• KATANO, KIYOAKI;OGINO, HIROKO;IWAMATSU, KATSUYOSHI;NAKABAYASHI, SATORU;YO+, J. ANTIBIOTICS, 43,(1990) N, C. 1150-1159
  作者：KATANO, KIYOAKI、OGINO, HIROKO、IWAMATSU, KATSUYOSHI、NAKABAYASHI, SATORU、YO+

  DOI：——

  日期：——
• One-Pot Synthesis of Multi-Substituted 4-Pyrones by a Gold- Catalyzed Cascade of Wolff Rearrangement/[4+2] Cycloaddition/ Elimination Reactions
  作者：Pratik Neupane、Likai Xia、Yong Rok Lee

  DOI：10.1002/adsc.201301086

  日期：2014.8.11

  AbstractAn efficient one‐pot method is described for the synthesis of a variety of di‐ and trisubstituted 4‐pyrones based on the gold‐catalyzed cascade reactions between cyclic or acyclic diazodicarbonyl compounds and vinyl ethers. The key strategy used involves the gold‐catalyzed Wolff rearrangement of diazo compounds followed by [4+2] cycloaddition and elimination. This methodology is also applied to the synthesis of tetrasubstituted 4‐pyrones.magnified image