p-xylylene | 502-86-3

• 分子结构分类: 有机化合物 - 碳氢化合物衍生物 - 醌二甲烷类
• 英文名称: p-xylylene
• 英文别名: 1,4-quinonedimethane；1,4-quinodimethane；benzoquinodimethane；p-quinodimethane；3,6-dimethylene-cyclohexa-1,4-diene；3,6-Dimethylen-cyclohexa-1,4-dien；3,6-Dimethylidenecyclohexa-1,4-diene
• CAS: 502-86-3
• 化学式: C₈H₈
• 分子量: 104.152
• InChiKey: NRNFFDZCBYOZJY-UHFFFAOYSA-N

物化性质

• 沸点：
  156.8±7.0 °C(Predicted)
• 密度：
  0.87±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.4
• 重原子数：
  8
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为反应物：
  描述：

  p-xylylene 在 氧气 、 丙酮 作用下， 生成 对苯二甲醛
  参考文献：
  名称：

  Preparation of aromatic aldehydes and alcohols

  摘要：

  公开号：

  US02864865A1
• 作为产物：
  描述：

  4-methylbenzyl radical 生成 p-xylylene
  参考文献：
  名称：

  Mechanism of Formation of the Quinonoid Hydrocarbon CH₂:C₆H₄:CH₂

  摘要：

  Para-xylyl radicals were generated by pyrolysing para-xylyl bromide in the presence of toluene or of para-xylene. Investigation of their behavior led to the conclusion that the quinonoid hydrocarbon CH2:C6H4:CH2 is formed by the disproportionation process. Further information about this reaction was secured by studying the pyrolysis of ω, ω′ dibromo para-xylene (Br·CH2·C6H4·CH2·Br). Semiquantitative treatment of the data indicates that the activation energy of the dissociation process CH2·C6H4·CH3→CH2:C̀6H6:CH2+His of the order 70 kcal/mole. Consequently, the dissociation process is too slow to account for the formation of the quinonoid hydrocarbon, at temperatures below 1100°K. We therefore attribute the formation of the quinonoid hydrocarbon to the disproportionation reaction. Reinvestigation of the pyrolysis of benzyl bromide confirmed the past results and particularly the value for D(C6H5·CH2–Br). It was shown that the rate constant for the decomposition of para-xylyl bromide is essentially equal to the rate constant for the decomposition of benzyl bromide, and it appears that the rate constant for the decomposition of ω, ω′ dibromo para-xylene is higher by statistical factor of 2 from the rate constant of the decomposition of para-xylyl bromide.

  DOI：

  10.1063/1.1739937

文献信息

• Rearrangements of the isomeric tolylmethylenes
  作者：Orville L. Chapman、Jeffery W. Johnson、Robert J. McMahon、Paul R. West

  DOI：10.1021/ja00210a032

  日期：1988.1

  Obtention de styrene et de benzocyclobutene. Un seul mecanisme decrit les processus de transposition thermique et photochimique

  获得苯乙烯和苯并环丁烯。Un seul mecanisme decrit les processus de transposition thermique et photochimique
• Polymer Fibers as Carriers for Homogeneous Catalysts
  作者：Michael Stasiak、Armido Studer、Andreas Greiner、Joachim H. Wendorff

  DOI：10.1002/chem.200601555

  日期：2007.7.16

  This paper describes a polymer fiber-based approach for the immobilization of homogeneous catalysts. The goal is to generate products that are free of catalysts which would be of great importance for the development of optoelectronic or pharmaceutical compounds. Electrospinning was employed to prepare the non-woven fiber assembly composed of polystyrene. The homogeneous catalyst scandium triflate was

  本文介绍了一种基于聚合物纤维的均相催化剂固定化方法。目的是产生不含催化剂的产物，这对于光电子或药物化合物的开发非常重要。使用静电纺丝来制备由聚苯乙烯组成的非织造纤维组件。在静电纺丝过程中，均一催化剂三氟甲磺酸scan固定在聚苯乙烯纤维上，并使用纤维模板方法固定在相应的核壳纤维上。每个纤维催化体系都进行了亚氨基羟醛和氮杂-狄尔斯-阿尔德模型反应。
• The pyrolysis of p-xylene
  作者：John R. Schaefgen

  DOI：10.1002/pol.1955.120157917

  日期：1955.1

  A quantitative study of the pyrolysis of p-xylene at temperatures from 795° to 920° at low pressures has been made using a flow system at low contact times. A mechanism is postulated to account for the principal products. The primary rate controlling reactions are the dissociation of either a CH bond in the methyl side chain or a CC bond from the ring to the methyl group, the activation energies of

  对二甲苯在 795° 至 920° 温度下在低压下的热解进行了定量研究，该研究使用流动系统在低接触时间进行。假设有一个机制来解释主要产品。主要的速率控制反应是甲基侧链中的 CH 键或从环到甲基的 CC 键的解离，其活化能分别为 79 和 82 kcal。有证据表明中间体对二甲苯分子的存在，以及它通过从最初形成的对甲基苄基自由基的歧化而形成。描述了对二甲苯与马来酸酐或氯丁二烯的共聚。
• Mechanistic studies on the photogeneration of o- and p-xylylenes from α,α′-dichloroxylenes
  作者：Miguel A. Miranda、Enrique Font-Sanchis、Julia Pérez-Prieto、J. C. Scaiano

  DOI：10.1039/a802016g

  日期：——

  Two-colour two-laser techniques have unambiguously proved that photolysis of the o-/p-(chloromethyl)benzyl radical leads to the sequential two-photon generation of o-/p-xylylene from α,α′-dichloro-o-/p-xylene.

  双色双激光技术明确证明，邻/对（氯甲基）苄基自由基的光解导致从δ,δâ²-二氯-/对二甲苯依次生成邻/对二甲苯。
• Formation of p-xylylene from p-xylene by a two-photon process and hexamethyl Dewar benzene from hexamethylbenzene by a one-photon process at 193nm
  作者：Naoya Mitsubayashi、Tomoyuki Yatsuhashi、Nobuaki Nakashima

  DOI：10.1016/j.jphotochem.2011.02.031

  日期：2011.4

  While studying a series of methyl-substituted benzenes, C6H6−n(CH3)n with n = 2, 3, 4, 6, and perfluorobenzene in the gas phase using 193-nm laser flash photolysis, we observed the formation of p-xylylene (benzoquinodimethane) due to the elimination of two hydrogen atoms as a result of a two-photon process. The results were explained in terms of an intermediate hot molecule formed by internal conversion

  虽然研究一系列甲基取代的苯，C 6 ħ 6- Ñ（CH 3）ñ与Ñ  = 2，3，4，6，和使用193纳米的激光闪光光解气相全氟苯，我们观察到形成的p-二甲苯（苯并醌二甲烷）是由于两次光子过程而消除了两个氢原子。用内部转化形成的中间热分子解释了结果，该中间热分子最终导致了基态电子状态。在存在外来气体的情况下，观察到甲苯，二甲苯，均三甲苯和全氟苯对光产物的二次依赖性，而对丁二烯和六甲基苯则观察到线性依赖性。从六甲基苯的光解中检测到杜瓦瓶型苯。