2,6-Dimethoxyphenol anion | 113947-82-3

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: 2,6-Dimethoxyphenol anion
• 英文别名: 2,6-Dimethoxyphenolate
• CAS: 113947-82-3
• 化学式: C₈H₉O₃
• 分子量: 153.158
• InChiKey: KLIDCXVFHGNTTM-UHFFFAOYSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  1.8
• 重原子数：
  11
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  41.5
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  2,6-Dimethoxyphenol anion 、 Uric acid radical 以 水 为溶剂， 生成 2,6-二甲氧基苯氧基 、 urate
  参考文献：
  名称：

  尿酸的抗氧化机制

  摘要：

  尿酸的单电子氧化产生尿酸盐自由基，通过脉冲辐射分解和氧摄取测量在水溶液中进行研究。测定尿酸自由基的酸碱性质，即pK{sub a1} = 3.1 {plus minus} 0.1 和pK {sub a2} = 9.5 {plus minus} 0.1。自由基与氧的反应太慢而无法测量，k < 10{sup {minus}2} dm{sup 3} mol{sup {minus}1} s{sup {minus}1}。单电子氧化还原电位与 NHE 的关系，E{sub 7} = 0.59 V，源自氧化还原电位的 pH 依赖性，该电位通过在 pH 7 和 8.9 下测量的值以及先前在 pH 13 下确定的值拟合。尿酸与氧化物质和过氧自由基的快速反应表明尿酸可能是一种水溶性生理抗氧化剂。

  DOI：

  10.1021/ja00197a042
• 作为产物：
  描述：

  2,6-二甲氧基苯氧基 在 ferrocenedicarboxylate 作用下， 以 水 为溶剂， 生成 2,6-Dimethoxyphenol anion
  参考文献：
  名称：

  Use of the Hammett correlation and .delta.+ for calculation of one-electron redox potentials of antioxidants

  摘要：

  Spectral, acid-base, and redox properties of methoxyphenoxyl radicals were determined in aqueous solutions by pulse radiolysis. Except for 2,6-dimethoxyphenoxyl, with lambda(max) < 300 nm, methoxyphenoxyl radicals absorb in the visible spectrum, with high molar absorptivities. From the effect of ionic strength on the rate of radical decay, a pK(a) < 2 was estimated for the deprotonation of phenolic radical cations. The oxidation potentials of methoxyphenols were determined from the electron-transfer equilibria with inorganic redox standards. The largest effect of methoxy groups on oxidation potential was observed for 2,6-dimethoxyphenol, E7 = 0.58 V vs NHE, whereas the effect of meta substitution was minimal for 3,5-dimethoxyphenol, E7 = 0.85 V, yet this was 0.12 V lower than the measured E7 of 0.97 V for unsubstituted phenol. The reduction potential E7 of methoxyphenoxyl radicals satisfies the Hammett correlation using Brown sigma+ substituent constants, as do other monosubstituted phenoxyls if the additivity of sigma+ values is assumed and the state of protonation of the substituents is taken into consideration. The derived sigma+(CH3O)m value of -0.14, in contrast to reported positive values, indicates the contribution of the methoxy group, even in the meta position, to charge delocalization and resonant stabilization of the phenoxyl radical. The contribution of the ring structure to more negative sigma+ values was observed, as expected. Use of the Hammett correlation is suggested for rapid estimation and accurate calculation of the redox potentials of polysubstituted phenolic antioxidants.

  DOI：

  10.1021/j100179a054

文献信息

• Use of the Hammett correlation and .delta.+ for calculation of one-electron redox potentials of antioxidants
  作者：Slobodan V. Jovanovic、Mihajilo Tosic、Michael G. Simic

  DOI：10.1021/j100179a054

  日期：1991.12

  Spectral, acid-base, and redox properties of methoxyphenoxyl radicals were determined in aqueous solutions by pulse radiolysis. Except for 2,6-dimethoxyphenoxyl, with lambda(max) < 300 nm, methoxyphenoxyl radicals absorb in the visible spectrum, with high molar absorptivities. From the effect of ionic strength on the rate of radical decay, a pK(a) < 2 was estimated for the deprotonation of phenolic radical cations. The oxidation potentials of methoxyphenols were determined from the electron-transfer equilibria with inorganic redox standards. The largest effect of methoxy groups on oxidation potential was observed for 2,6-dimethoxyphenol, E7 = 0.58 V vs NHE, whereas the effect of meta substitution was minimal for 3,5-dimethoxyphenol, E7 = 0.85 V, yet this was 0.12 V lower than the measured E7 of 0.97 V for unsubstituted phenol. The reduction potential E7 of methoxyphenoxyl radicals satisfies the Hammett correlation using Brown sigma+ substituent constants, as do other monosubstituted phenoxyls if the additivity of sigma+ values is assumed and the state of protonation of the substituents is taken into consideration. The derived sigma+(CH3O)m value of -0.14, in contrast to reported positive values, indicates the contribution of the methoxy group, even in the meta position, to charge delocalization and resonant stabilization of the phenoxyl radical. The contribution of the ring structure to more negative sigma+ values was observed, as expected. Use of the Hammett correlation is suggested for rapid estimation and accurate calculation of the redox potentials of polysubstituted phenolic antioxidants.
• Antioxidation mechanisms of uric acid
  作者：Michael G. Simic、Slobodan V. Jovanovic

  DOI：10.1021/ja00197a042

  日期：1989.7

  One-electron oxidation of uric acid generates the urate radical, which was studied in aqueous solution by pulse radiolysis and oxygen-uptake measurements. Acid-base properties of the uric acid radical were determined, i.e., pKsub a1} = 3.1 plus minus} 0.1 and pKsub a2} = 9.5 plus minus} 0.1. The reaction of the radical with oxygen was too slow to be measured, k < 10sup minus}2} dmsup 3} molsup minus}1}

  尿酸的单电子氧化产生尿酸盐自由基，通过脉冲辐射分解和氧摄取测量在水溶液中进行研究。测定尿酸自由基的酸碱性质，即pKsub a1} = 3.1 plus minus} 0.1 和pK sub a2} = 9.5 plus minus} 0.1。自由基与氧的反应太慢而无法测量，k < 10sup minus}2} dmsup 3} molsup minus}1} ssup minus}1}。单电子氧化还原电位与 NHE 的关系，Esub 7} = 0.59 V，源自氧化还原电位的 pH 依赖性，该电位通过在 pH 7 和 8.9 下测量的值以及先前在 pH 13 下确定的值拟合。尿酸与氧化物质和过氧自由基的快速反应表明尿酸可能是一种水溶性生理抗氧化剂。