5-Phenyl-1-methyl-6-methylene-1,2,3,6-tetrahydropyrazine | 141089-26-1

• 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: 5-Phenyl-1-methyl-6-methylene-1,2,3,6-tetrahydropyrazine
• 英文别名: 1-methyl-6-methylene-5-phenyl-1,2,3,6-tetrahydropyrazine；1-Methyl-6-methylidene-5-phenyl-2,3-dihydropyrazine
• CAS: 141089-26-1
• 化学式: C₁₂H₁₄N₂
• 分子量: 186.257
• InChiKey: WZTBIMYQQHHLHA-UHFFFAOYSA-N

物化性质

• 沸点：
  294.0±33.0 °C(Predicted)
• 密度：
  1.02±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.3
• 重原子数：
  14
• 可旋转键数：
  1
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  15.6
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  5-Phenyl-1-methyl-6-methylene-1,2,3,6-tetrahydropyrazine 在 重水 作用下， 以 氘代二甲亚砜 为溶剂， 生成 6-(Dideuteriomethylidene)-1-methyl-5-phenyl-2,3-dihydropyrazine
  参考文献：
  名称：

  5-甲基-2,3-二氢吡嗪的潜在烯胺官能团。

  摘要：

  从理论和经验上研究了甲基取代的二氢吡嗪（DHP）衍生物互变异构化为潜在的烯胺形式。在通过密度泛函理论计算模拟的两种类型的氢转移模型中，5,6-二甲基-2,3-二氢吡嗪（1）和5-甲基-6-苯基-2,3-的简单分子内氢转移机理二氢吡嗪（3）需要较高的活化能来实现互变异构，而水辅助分子间氢转移机理产生的活化能较小（约160 kJ / mol）。在50％（v / v）D（2）O /二甲基亚砜-d（6）溶液中进行3的氘交换反应的检查显示了5甲基基团的温度依赖性和逐步氘交换。化合物3与异氰酸苯酯在乙腈中反应，得到5-甲基的单加合物（7），和环状加合物（8）。这些结果表明了5-甲基-2,3-二氢吡嗪（亚胺形式）与潜在的烯胺互变异构体的互变异构现象，并表明在生理条件下，DHP可能在很大程度上表现为烯胺。

  DOI：

  10.1248/cpb.58.922
• 作为产物：
  描述：

  2-Phenyl-2-hydroxy-3-methyl-5,6-dihydro-1-methylpyrazine 生成 5-Phenyl-1-methyl-6-methylene-1,2,3,6-tetrahydropyrazine
  参考文献：
  名称：

  Reaction of .alpha.-diketones with 2-amino alcohols. Intramolecular competitive 6-exo-trig vs 5-endo-trig processes. A systematic and kinetic study

  摘要：

  2-Aminoethanol and C-substituted derivatives 1 react with diacetyl, benzil, and 1-phenyl-1,2-propanedione, models of alpha-diketones 2 to give with remarkable regio- and stereoselectivity 2-hydroxy-5,6-dihydro-2H-1,4-oxazines 3, cis-octahydro[1,4]oxazino[3,2-b]oxazines 4, alpha-imino ketones 6, 2-acetyl-1,3-oxazolidines 7, N,N'-bis(2-hydroxy-2-methylpropyl)-2,3-butanediimines 8, and 2,2'-dimethyl-2,2'-bioxazolidines 9 depending on the nature of the reagents and the reaction conditions. On the basis of isolated intermediates, a reasonable mechanism taking into account the stereoelectronic effects observed on the cyclization has been proposed for these processes. In addition, a kinetic study of the ring-chain-ring tautomeric equilibrium of oxazines 3a-c, 3i-k, and 3o-q has been studied by H-1 NMR and C-13 NMR. In solution, compounds 3a-c and 3i-k exhibit a three-component tautomeric equilibria consisting of the following: the beta-iminohemiacetal 3, the beta-hydroxyimino ketone 6, and the 2-acetyl- or 2-benzoyl-1,3-oxazolidine 7. The calculated rate constants for this process show that the equilibrium is shifted toward the formation of the five-membered ring by 0.4-4.8 kJ mol-1 over the six-membered ring depending on the substitution patterns. Compounds 3p-q exist in solution as equimolar mixtures of the ring and open-chain tautomers. Compound 3o exists predominantly in the open-chain form. In addition, 2-acylthiazolidines 13a-c do not evidence any dynamic processes in solution.

  DOI：

  10.1021/jo00034a046

文献信息

• Reaction of .alpha.-diketones with 2-amino alcohols. Intramolecular competitive 6-exo-trig vs 5-endo-trig processes. A systematic and kinetic study
  作者：Benito Alcaide、Joaquin Plumet、Ignacio M. Rodriguez-Campos、Severino Garcia-Blanco、Sagrario Martinez-Carrera

  DOI：10.1021/jo00034a046

  日期：1992.4

  2-Aminoethanol and C-substituted derivatives 1 react with diacetyl, benzil, and 1-phenyl-1,2-propanedione, models of alpha-diketones 2 to give with remarkable regio- and stereoselectivity 2-hydroxy-5,6-dihydro-2H-1,4-oxazines 3, cis-octahydro[1,4]oxazino[3,2-b]oxazines 4, alpha-imino ketones 6, 2-acetyl-1,3-oxazolidines 7, N,N'-bis(2-hydroxy-2-methylpropyl)-2,3-butanediimines 8, and 2,2'-dimethyl-2,2'-bioxazolidines 9 depending on the nature of the reagents and the reaction conditions. On the basis of isolated intermediates, a reasonable mechanism taking into account the stereoelectronic effects observed on the cyclization has been proposed for these processes. In addition, a kinetic study of the ring-chain-ring tautomeric equilibrium of oxazines 3a-c, 3i-k, and 3o-q has been studied by H-1 NMR and C-13 NMR. In solution, compounds 3a-c and 3i-k exhibit a three-component tautomeric equilibria consisting of the following: the beta-iminohemiacetal 3, the beta-hydroxyimino ketone 6, and the 2-acetyl- or 2-benzoyl-1,3-oxazolidine 7. The calculated rate constants for this process show that the equilibrium is shifted toward the formation of the five-membered ring by 0.4-4.8 kJ mol-1 over the six-membered ring depending on the substitution patterns. Compounds 3p-q exist in solution as equimolar mixtures of the ring and open-chain tautomers. Compound 3o exists predominantly in the open-chain form. In addition, 2-acylthiazolidines 13a-c do not evidence any dynamic processes in solution.
• Latent Enamine Functionality of 5-Methyl-2,3-dihydropyrazines
  作者：Shigeru Ito、Tomoya Hirano、Akiko Sugimoto、Hiroyuki Kagechika、Shinji Takechi、Tadatoshi Yamaguchi

  DOI：10.1248/cpb.58.922

  日期：——

  Tautomerization of methyl-substituted dihydropyrazine (DHP) derivatives to their latent enamine form was investigated theoretically and empirically. Among two types of hydrogen transfer model simulated by means of density functional theory calculation, a simple intramolecular hydrogen shift mechanism for 5,6-dimethyl-2,3-dihydropyrazine (1) and 5-methyl-6-phenyl-2,3-dihydropyrazine (3) required high

  从理论和经验上研究了甲基取代的二氢吡嗪（DHP）衍生物互变异构化为潜在的烯胺形式。在通过密度泛函理论计算模拟的两种类型的氢转移模型中，5,6-二甲基-2,3-二氢吡嗪（1）和5-甲基-6-苯基-2,3-的简单分子内氢转移机理二氢吡嗪（3）需要较高的活化能来实现互变异构，而水辅助分子间氢转移机理产生的活化能较小（约160 kJ / mol）。在50％（v / v）D（2）O /二甲基亚砜-d（6）溶液中进行3的氘交换反应的检查显示了5甲基基团的温度依赖性和逐步氘交换。化合物3与异氰酸苯酯在乙腈中反应，得到5-甲基的单加合物（7），和环状加合物（8）。这些结果表明了5-甲基-2,3-二氢吡嗪（亚胺形式）与潜在的烯胺互变异构体的互变异构现象，并表明在生理条件下，DHP可能在很大程度上表现为烯胺。