| 143245-62-9

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 香豆素
• CAS: 143245-62-9
• 化学式: C₁₃H₁₇O₂
• 分子量: 205.277
• InChiKey: XVGSVHQXVNBLIE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.47
• 重原子数：
  15.0
• 可旋转键数：
  0.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.54
• 拓扑面积：
  29.13
• 氢给体数：
  0.0
• 氢受体数：
  1.0

反应信息

• 作为产物：
  描述：

  2,2,4,6,7-pentamethylcoumaran-5-ol 在 苯酚 作用下， 以 乙腈 为溶剂， 生成
  参考文献：
  名称：

  The Surprisingly High Reactivity of Phenoxyl Radicals

  摘要：

  Rate constants have been measured in nonaqueous media for hydrogen atom abstraction by the phenoxyl radical from some biologically important phenols and related compounds. Although the thermochemistry for these reactions must be very similar to the thermochemistry for H atom abstraction from the same substrate by a peroxyl radical, the phenoxyl rate constants, k(5), are ca. 100-300 times greater than the (already well-known) peroxyl rate constants, k(1). For example, with alpha-tocopherol in benzene/di-tert-butyl peroxide (1:3, v/v) k(5)(293K) = 1.1 X 10(9) M(-1) s(-1) vs k(1)(303K) = 3.2 X 10(6) M(-1) s(-1) in a similar nonpolar medium, and with ubiquinol-10 in the same solvent mixture k(5)(293K) = 8.4 X 10(7) M(-1) s(-1), while the corresponding value for k(1) is 3.5 X 10(5) M(-1) s(-1). The greater reactivity of the phenoxyl radical has been traced to the fact that the Arrhenius preexponential factors are much larger than for the corresponding peroxyl radical reactions, i.e., A(5) similar to 10(2)A(1). For example, with alpha-naphthol log(A(5)/M(-1) s(-1)) = 8.9 and E(5) = 2.2 kcal/mol vs log(A(1)/M(-1) s(-1)) = 6.4 and E(1) = 1.7 kcal/mol. The preexponential factors for II-atom donors more reactive than alpha-naphthol are even greater; for example, with alpha-tocopherol in CH3CN/di-tert-butyl peroxide (1:2, v/v) log(A(5)/M(-1) s(-1)) = 10.0 and E(5) 2.0 kcal/mol, and with ubiquinol-0 in benzene/di-tert-butyl peroxide (1:3, v/v) log(A(5)/M(-1) s(-1)) = 10.5 and E(5) = 3.5 kcal/mol. The role that intermediate hydrogen-bonded complexes between the reacting radical and the phenolic hydrogen donor may play in these reactions is discussed, and it is pointed out that our results are likely to be relevant to in vivo radical chemistry.

  DOI：

  10.1021/ja00100a005

文献信息

• Synthesis and stopped-flow investigation of antioxidant activity of tocopherols. Finding of new tocopherol derivatives having the highest antioxidant activity among phenolic antioxidants
  作者：Kazuo Mukai、Kazuya Okabe、Hironobu Hosose

  DOI：10.1021/jo00264a011

  日期：1989.2