durosemiquinone radical | 22311-37-1

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: durosemiquinone radical
• 英文别名: 4-Hydroxy-2,3,5,6-tetramethyl-phenoxyl；Tetramethyl-p-benzosemichinon；Durosemichinon-Radikal；Durosemichinonradikal；Durochinon-Radikal；Durosemichinon
• CAS: 22311-37-1
• 化学式: C₁₀H₁₃O₂
• 分子量: 165.212
• InChiKey: ADMYSSDKFCJUDT-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.6
• 重原子数：
  12
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.4
• 拓扑面积：
  37.3
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  durosemiquinone radical 以 乙腈 为溶剂， 生成 四甲基氢醌 、 杜醌
  参考文献：
  名称：

  Becker, H. G. O.; Jirkovsky, J.; Fojtik, A., Journal fur praktische Chemie (Leipzig 1954), 1982, vol. 324, # 4, p. 505 - 511

  摘要：

  DOI：
• 作为产物：
  描述：

  四甲基氢醌 在 air 作用下， 生成 durosemiquinone radical
  参考文献：
  名称：

  Paramagnetic Resonance of Methyl‐ and Chloro‐Substitutedp‐Benzosemiquinones

  摘要：

  Detailed measurements, made under conditions of high resolution, of the paramagnetic resonance spectra of the negative radical ions of all the methyl- and chloro-substituted p-benzosemiquinones are reported. All the spectra exhibited hyperfine structure which is accounted for in terms of interactions between the unpaired electron and all the protons in the radicals; no chlorine hyperfine splittings were observed. In some of the chlorine compounds anomalous lines, not attributable to the chloro-substituted p-benzosemiquinone ion, appeared; these presumably arise from radicals produced by side reactions. Microwave power saturation was encountered in all the spectra examined. Line widths of all the spectra were observed to depend markedly on the microwave power and on the concentration of the hydroquinone from which the semiquinone was prepared. Separations of the hyperfine components were measured to a high degree of accuracy and splitting constants for individual protons were calculated from the measurements using the method of least squares. Proton splitting constants ranged from a minimum of 1.714 gauss for the methyl group protons in 2,3-dimethyl semiquinone ion to a maximum of 2.595 gauss for the ring protons in that same compound. The variation of the splitting constants with chlorine and methyl group substitutions are shown to obey a nearly additive relation.

  DOI：

  10.1063/1.1730073

文献信息

• Photoreduction of p-Benzoquinones: Effects of Alcohols and Amines on the Intermediates and Reactivities in Solution¶
  作者：Helmut Görner

  DOI：10.1562/0031-8655(2003)078<0440:popeoa>2.0.co;2

  日期：——

  2,6-dimethyl-, chloro-, 2,5-dichloro-1,4-benzoquinone, duroquinone and chloranil, was studied in nonaqueous solvents by UV–vis spectroscopy using nanosecond laser pulses at 308 nm. The reactivity of the triplet state (3Q*) of the quinones with 2-propanol in the absence of water is largest for BQ and depends mainly on the quinone structure, whereas the rate constant of electron transfer from amines,

  摘要 1,4-苯醌 (BQ) 和烷基-、Cl- 和相关衍生物的光化学，例如甲基-、2,6-二甲基-、氯-、2,5-二氯-1,4-苯醌、duroquinone 和使用 308 nm 纳秒激光脉冲通过紫外-可见光谱在非水溶剂中研究了氯苯醌。在没有水的情况下，醌与 2-丙醇的三重态 (3Q*) 的反应性对于 BQ 最大，主要取决于醌结构，而来自胺的电子转移速率常数，例如三乙胺 (TEA)或 1,4-二氮杂双环 [2.2.2] 辛烷，接近 BQ 和大多数衍生物的扩散控制极限。时间分辨电导率测量支持电子从胺转移到 3Q* 后的光致电荷分离以及随后的电荷重组或中和。半醌自由基 (•QH/Q•–) 衰变动力学的半衰期在很大程度上取决于供体和介质。在各种条件下测量到对苯二酚的光转化，量子产率 λirr = 254 nm，随着 2-丙醇和 TEA 浓度的增加而增加。概述了 3Q*、•QH/Q•– 自由基和光
• An electron spin resonance and time-resolved CIDEP study of the oxidation of ascorbic acid by pyruvic acid, duroquinone, and vitamin K₁
  作者：M. Catherine Depew、Babatunde B. Adeleke、Jeffrey K. S. Wan

  DOI：10.1139/v81-390

  日期：1981.9.15

  The photooxidation of vitamin C by pyruvic acid and its derivatives, duroquinone, and vitamin K1, is systematically studied by the combined esr and time-resolved CIDEP technique. Because of the unique property of the triplet pyruvic acid which is different from that of the duroquinone triplet, the choice of these model systems allowed the CIDEP observations of the initial polarization of the ascorbate

  通过结合 esr 和时间分辨 CIDEP 技术系统地研究了丙酮酸及其衍生物、duroquinone 和维生素 K1 对维生素 C 的光氧化。由于三线态丙酮酸与杜罗醌三线态不同的独特性质，这些模型系统的选择允许 CIDEP 观察抗坏血酸根阴离子的初始极化及其反初级自由基在增强的吸收性或发射模式。结果表明，三联体维生素 K1 对维生素 C 进行了有效的光氧化，并且后者具有与三联体醌类相似的特性。在涉及维生素 C 和丙酮酸的光氧化系统中，调节水溶液的 pH 值为观察丙酮酸阴离子和抗坏血酸阴离子这两种阴离子之间的光化学反应提供了机会。有观点支持电子转移机制用于维生素 C 的氧化...
• Bridges; Porter, Proceedings of the Royal Society of London, Series A: Mathematical, Physical and Engineering Sciences, 1958, vol. 244, p. 259,271
  作者：Bridges、Porter

  DOI：——

  日期：——
• Primary photochemical processes in aromatic molecules. Part 4.—Side-chain photolysis in rigid media
  作者：G. Porter、E. Strachan

  DOI：10.1039/tf9585401595

  日期：——
• Triplet mechanism of CIDNP in the photolysis of benzoquinones as studied by dynamic nuclear polarization
  作者：Qing Xiang Meng、Kouei Suzuki、Kiminori Maeda、Masahide Terazima、Tohru Azumi

  DOI：10.1021/j100109a005

  日期：1993.2

  CIDNP and CIDNP-detected ESR spectra are observed in the photolysis of benzoquinone and its methyl derivatives. In low concentrations of solutions, the sign of the CIDNP of the ring and methyl protons of benzoquinones is in accord with the prediction from the Kaptein rule; however, at high concentrations, the sign is reversed. From the sign of the dynamic nuclear polarization that is observed as a component of the CIDNP-detected ESR spectrum, the mechanism of the cross-relaxation in free radicals is determined. From the correlation between the sign of the dynamic nuclear polarization and the sign of the CIDNP, the anomalous sign of the CIDNP observed at high concentrations is ascribed to generation of an electron spin polarization by the anisotropy in the intersystem crossing (triplet mechanism) and subsequent transfer of this polarization to the nuclei by the cross-relaxation in free radicals. Thus, the triplet mechanism of CIDNP is well substantiated.