2,3-dihydro-3-methylene-2-methylbenzofuran-2-ol | 135831-62-8

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 香豆素
• 英文名称: 2,3-dihydro-3-methylene-2-methylbenzofuran-2-ol
• 英文别名: 2,3-dihydro-3-methenyl-2-methylbenzofuran-2-ol；2-methyl-3-methylidene-1-benzofuran-2-ol
• CAS: 135831-62-8
• 化学式: C₁₀H₁₀O₂
• 分子量: 162.188
• InChiKey: QDHJAAKWTFJQAA-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.8
• 重原子数：
  12.0
• 可旋转键数：
  0.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.2
• 拓扑面积：
  29.46
• 氢给体数：
  1.0
• 氢受体数：
  2.0

反应信息

• 作为产物：
  描述：

  2A,7B-二甲基-2A,7B-二氢[1,2]二氧四环并[3,4-b][1]苯并呋喃 以 氘代氯仿 为溶剂， 反应 72.0h， 生成 2,3-dihydro-3-methylene-2-methylbenzofuran-2-ol
  参考文献：
  名称：

  Thermal and Bromide Ion-Catalyzed Rearrangement of Benzofuran Dioxetanes to 1-Oxaspiro[2.5]octa-5,7-dien-4-ones

  摘要：

  The reaction of the tetrasubstituted benzofuran dioxetanes 2 with various nucleophiles, e.g. Br-, Cl-, I-, and HN(i-Pr)(2), was investigated and the unprecedented bromide ion-catalyzed rearrangement to the hitherto unknown 1-oxaspiro[2.5]octa-5,7-dien-4-ones 4 observed. As the mechanism, an S(N)2 attack of the bromide ion at the O-3 of the peroxide bond is proposed, in which the resulting hypobromite intermediate 8 rearranges to the spiroepoxide 4 by opening of the furan ring and expulsion of the bromide ion through intramolecular nucleophilic attack of the phenolate ion on the O-Br bond. This unique reaction type is limited to the bromide and the iodide ions, since none of the other nucleophiles led to the spiroepoxide 4. On thermolysis, the labile spiroepoxides 4 rearrange to the benzodioxoles 5, and at low temperature, the dimers 6 were formed by the Diels-Alder reaction. 4-Methyl-1,2,4-triazoline-3,5-dione (MTAD) gave with the spiroepoxide 4a the Diels-Alder product 7a. The thermolysis of the dioxetanes 2 gave, besides the conventional C-C cleavage products 3, the dioxoles 5 by rearrangement of the intermediary spiroepoxides 4. In the latter reaction, electron donors favor the formation of the dioxoles 5 and electron accepters the C-C cleavage products 3. The intermediacy of the spiroepoxides 4 in the thermolysis of the dioxetanes 2 was established by trapping of the spiroepoxide 4a with MTAD in the form of the [4 + 2] cycloaddition product 7a. For the thermal rearrangement 2 --> 4, the electron-rich arene moiety is proposed to serve as an intramolecular nucleophile which initiates spiroepoxide formation. Both the bromide ion-catalyzed and the thermal rearrangements are unprecedented in dioxetane chemistry.

  DOI：

  10.1021/ja00094a029

文献信息

• Adam, Waldemar; Ahrweiler, Michael; Sauter, Markus, Chemische Berichte, 1994, vol. 127, # 5, p. 941 - 946
  作者：Adam, Waldemar、Ahrweiler, Michael、Sauter, Markus

  DOI：——

  日期：——
• Chemical model studies on the mutagenesis of benzofuran dioxetanes in the Ames test: evidence for the benzofuran epoxide as ultimate mutagen
  作者：W. Adam、L. Hadjiarapoglou、T. Mosandl、C. R. Saha-Moeller、D. Wild

  DOI：10.1021/ja00021a029

  日期：1991.10

  The synthesis of the first benzofuran epoxide 3a was achieved by epoxidation of the benzofuran 1a with dimethyldioxirane and alternatively by deoxygenation of the benzofuran dioxetane 2a with sulfides. This labile epoxide formed with nucleophiles such as water, methanol, thiophenol, and imidazole the corresponding adducts 13a-16a. In contrast to epoxide 3a, the dioxetanes 2 required acid catalysis (CF3CO2H) for the addition of water, methanol, and azide ion to give the corresponding adducts 9-11; in the absence of nucleophiles the allylic hydroperoxides 8 were formed. The decomposition of benzofuran dioxetanes 2 in the polar, protic solvents water and methanol afforded not only expected cleavage products 4 but also the 1,3-dioxols 5, the spiroepoxide dimer 6a, and the 1,4-dioxines 7. An intramolecular electron-transfer mechanism is postulated for the formation of the spiroepoxide, which subsequently dimerizes to 6a or rearranges into 5 and 7. Only the benzofuran epoxide 3a, besides the benzofuran dioxetanes 2, was mutagenic in the Salmonella typhimurium strain TA100. Therefore, we implicate the epoxide 3a as the ultimate mutagen responsible for the high mutagenic activity observed with dioxetane 2a in the Ames test. We postulate that in the oxidative metabolism of polycyclic arenes and heteroarenes the corresponding epoxides are generated from the intermediary dioxetanes by deoxygenation with sulfides.