4,4-diethoxy-2-methyl-3-phenyl-2-cyclobutenone | 178418-78-5

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 4,4-diethoxy-2-methyl-3-phenyl-2-cyclobutenone
• 英文别名: 4,4-diethoxy-2-methyl-3-phenylcyclobut-2-en-1-one
• CAS: 178418-78-5
• 化学式: C₁₅H₁₈O₃
• 分子量: 246.306
• InChiKey: TULBURNFNZLICW-UHFFFAOYSA-N

物化性质

• 沸点：
  346.4±42.0 °C(Predicted)
• 密度：
  1.10±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.81
• 重原子数：
  18.0
• 可旋转键数：
  5.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.4
• 拓扑面积：
  35.53
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  4,4-diethoxy-2-methyl-3-phenyl-2-cyclobutenone 在 四氯化锡 、 二(三甲基甲硅烷基)乙炔 作用下， 以 二氯甲烷 为溶剂， 反应 18.0h， 以19%的产率得到2-[Bis(trimethylsilyl)methylidene]-4-methyl-5-phenylcyclopent-4-ene-1,3-dione
  参考文献：
  名称：

  Formation of 2-[1-(Trimethylsilyl)alkylidene]-4-cyclopentene-1,3-dione from Lewis Acid-Catalyzed Reaction of Cyclobutenedione Monoacetal with Alkynylsilane:  Novel Cationic 1,2-Silyl Migrative Ring Opening and Subsequent 5-Exo-Trig Ring Closure

  摘要：

  An ethoxycarbenium ion intermediate, which was produced by the catalytic action of a Lewis acid on a cyclobutenedione monoacetal, reacted with phenyl(trimethylsilyl)acetylene to give a normal electrophilic substitution product. In sharp contrast, the same catalytic reaction with bis(trimethylsilyl)acetylene afforded a 2-methylene-4-cyclopentene-1,3-dione derivative as a ring expansion product instead of an alkynylation product. Butyl(trimethylsilyl)acetylene showed reactivity between the aforementioned compounds as a result of the formation of both types of products. In the reactions of such alkyl-substituted silylacetylenes, both E- and Z-isomers of 2-(1-silylalkylidene)cyclopentenediones were obtained in ratios dependent on the reaction temperature and the amount of Lewis acid. This rearrangement resulted from unprecedented cationic 1,2-silyl migration on the alkynylsilane and subsequent ring expansion promoted by the formed vinyl cation intermediate. A detailed mechanism of the novel ring-expansion route is discussed with the aid of PM3 calculations, especially for the reclosure step, which is explained by a 5-exo-trig cyclization rather than a pentadienyl cation electrocyclization.

  DOI：

  10.1021/jo961552w
• 作为产物：
  描述：

  方酸二乙酯 在 三氟乙酸酐 作用下， 以 四氢呋喃 、 乙醚 为溶剂， 反应 2.5h， 生成 4,4-diethoxy-2-methyl-3-phenyl-2-cyclobutenone
  参考文献：
  名称：

  将方酸衍生为高度取代的环丁烯酮的新方法：路易斯酸催化环丁烯-1,2-二酮单缩醛及其乙烯基与不饱和有机硅烷的反应，以及随后的加合物环转化

  摘要：

  本文描述了一种区域控制合成在 4 位具有不饱和取代基的高度取代的环丁烯酮的新方法，起始于可商购的方酸。环丁烯-1,2-二酮单缩醛（4,4-二乙氧基环丁烯酮）及其乙烯基（2,4-二乙氧基环丁烯酮）很容易从方酸二乙酯中获得，在 Et2O·BF3 存在下与烯丙基硅烷反应得到 4-烯丙基-4-乙氧基环丁烯酮在 2 位区域选择性地具有各种取代基。这些产物通过在二甲苯中回流有效地转化为高度取代的双环[3.2.0]庚烯酮。该方法的合成效用在三环系统的构建中得到了证明。使用丙二烯基硅烷、甲硅烷基烯醇醚进一步扩展路易斯酸催化的单缩醛反应，和甲硅烷基乙烯酮缩醛也提供相应的 4-取代产物。与上述 4-烯丙基化产物相比，4-炔丙基化和 4-酰基甲基化的 p...

  DOI：

  10.1246/bcsj.69.1353

文献信息

• New Method for Derivatization of Squaric Acid to Highly Substituted Cyclobutenones: Lewis Acid-Catalyzed Reaction of Cyclobutene-1,2-dione Monoacetal and Its Vinylog with Unsaturated Organosilanes, and Subsequent Ring Transformation of the Adducts
  作者：Yoshihiko Yamamoto、Masatomi Ohno、Shoji Eguchi

  DOI：10.1246/bcsj.69.1353

  日期：1996.5

  Described herein is a novel method for regio-controlled synthesis of highly substituted cyclobutenones having an unsaturated substituent at 4-position, starting from commercially available squaric acid. Both cyclobutene-1,2-dione monoacetal (4,4-diethoxycyclobutenone) and its vinylog (2,4-diethoxycyclobutenone), which were easily obtained from diethyl squarate, reacted with allylsilanes in the presence

  本文描述了一种区域控制合成在 4 位具有不饱和取代基的高度取代的环丁烯酮的新方法，起始于可商购的方酸。环丁烯-1,2-二酮单缩醛（4,4-二乙氧基环丁烯酮）及其乙烯基（2,4-二乙氧基环丁烯酮）很容易从方酸二乙酯中获得，在 Et2O·BF3 存在下与烯丙基硅烷反应得到 4-烯丙基-4-乙氧基环丁烯酮在 2 位区域选择性地具有各种取代基。这些产物通过在二甲苯中回流有效地转化为高度取代的双环[3.2.0]庚烯酮。该方法的合成效用在三环系统的构建中得到了证明。使用丙二烯基硅烷、甲硅烷基烯醇醚进一步扩展路易斯酸催化的单缩醛反应，和甲硅烷基乙烯酮缩醛也提供相应的 4-取代产物。与上述 4-烯丙基化产物相比，4-炔丙基化和 4-酰基甲基化的 p...
• Formation of 2-[1-(Trimethylsilyl)alkylidene]-4-cyclopentene-1,3-dione from Lewis Acid-Catalyzed Reaction of Cyclobutenedione Monoacetal with Alkynylsilane:  Novel Cationic 1,2-Silyl Migrative Ring Opening and Subsequent 5-<i>Exo</i>-<i>Trig</i> Ring Closure
  作者：Yoshihiko Yamamoto、Masashi Noda、Masatomi Ohno、Shoji Eguchi

  DOI：10.1021/jo961552w

  日期：1997.3.1

  An ethoxycarbenium ion intermediate, which was produced by the catalytic action of a Lewis acid on a cyclobutenedione monoacetal, reacted with phenyl(trimethylsilyl)acetylene to give a normal electrophilic substitution product. In sharp contrast, the same catalytic reaction with bis(trimethylsilyl)acetylene afforded a 2-methylene-4-cyclopentene-1,3-dione derivative as a ring expansion product instead of an alkynylation product. Butyl(trimethylsilyl)acetylene showed reactivity between the aforementioned compounds as a result of the formation of both types of products. In the reactions of such alkyl-substituted silylacetylenes, both E- and Z-isomers of 2-(1-silylalkylidene)cyclopentenediones were obtained in ratios dependent on the reaction temperature and the amount of Lewis acid. This rearrangement resulted from unprecedented cationic 1,2-silyl migration on the alkynylsilane and subsequent ring expansion promoted by the formed vinyl cation intermediate. A detailed mechanism of the novel ring-expansion route is discussed with the aid of PM3 calculations, especially for the reclosure step, which is explained by a 5-exo-trig cyclization rather than a pentadienyl cation electrocyclization.