3-Bromo-3-(bromomethyl)-4-(1-methylethyl)-1-oxetan-2-one | 135638-68-5

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 内酯类
• 英文名称: 3-Bromo-3-(bromomethyl)-4-(1-methylethyl)-1-oxetan-2-one
• 英文别名: 1-Oxetan-2-one, 3-bromo-3-(bromomethyl)-4-isopropyl-；3-bromo-3-(bromomethyl)-4-propan-2-yloxetan-2-one
• CAS: 135638-68-5；135638-69-6
• 化学式: C₇H₁₀Br₂O₂
• 分子量: 285.963
• InChiKey: VIEFWZSBUCBZIY-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.7
• 重原子数：
  11
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.86
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  3-Methylene-4-(1-methylethyl)-1-oxetan-2-one 在 溴 、 对苯二酚 作用下， 以 四氯化碳 为溶剂， 反应 480.0h， 以62%的产率得到3-Bromo-3-(bromomethyl)-4-(1-methylethyl)-1-oxetan-2-one
  参考文献：
  名称：

  .alpha.-Methylene .beta.-lactones as masked allenes and allene equivalents: some selected chemical transformations

  摘要：

  Selective chemical transformations have been performed on a number of alpha-methylene beta-lactones to illustrate that these highly functionalized heterocycles serve as useful building blocks in organic synthesis. Thus, thermal decarboxylation of these ''masked allenes'' provides a useful regioselective preparation of allenes with a predetermined substitution pattern. Nucleophilic addition takes place at the carbonyl group with ring opening, but free-radical addition, e.g., thiophenol, and electrophilic addition, e.g., bromine, proceed at the exomethylene group with preservation of the beta-lactone ring. [4 + 2] Cycloaddition with cyclopentadiene affords the expected beta-lactones, which on thermal decarboxylation lead to 2-alkylidenenorbornenes. This regio- and stereoselective transformation establishes the alpha-methylene beta-lactones as valuable allene equivalents. The alpha-methylene beta-lactones serve also as dipolarophiles by undergoing readily 1,3-dipolar cycloaddition with diazoalkanes. Reaction with Lawesson's reagent affords a hitherto unknown alpha-methylene beta-(S)-lactone.

  DOI：

  10.1021/jo00020a017

文献信息

• .alpha.-Methylene .beta.-lactones as masked allenes and allene equivalents: some selected chemical transformations
  作者：Waldemar Adam、Rainer Albert、Ludwig Hasemann、Victor O. Nava Salgado、Bernd Nestler、Eva Maria Peters、Karl Peters、Frank Prechtl、Hans Georg Von Schnering

  DOI：10.1021/jo00020a017

  日期：1991.9

  Selective chemical transformations have been performed on a number of alpha-methylene beta-lactones to illustrate that these highly functionalized heterocycles serve as useful building blocks in organic synthesis. Thus, thermal decarboxylation of these ''masked allenes'' provides a useful regioselective preparation of allenes with a predetermined substitution pattern. Nucleophilic addition takes place at the carbonyl group with ring opening, but free-radical addition, e.g., thiophenol, and electrophilic addition, e.g., bromine, proceed at the exomethylene group with preservation of the beta-lactone ring. [4 + 2] Cycloaddition with cyclopentadiene affords the expected beta-lactones, which on thermal decarboxylation lead to 2-alkylidenenorbornenes. This regio- and stereoselective transformation establishes the alpha-methylene beta-lactones as valuable allene equivalents. The alpha-methylene beta-lactones serve also as dipolarophiles by undergoing readily 1,3-dipolar cycloaddition with diazoalkanes. Reaction with Lawesson's reagent affords a hitherto unknown alpha-methylene beta-(S)-lactone.