methyl N-(1,1-dimethylethyl)benzenecarboximidate N-oxide | 118891-54-6

• 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: methyl N-(1,1-dimethylethyl)benzenecarboximidate N-oxide
• 英文别名: (E)-tert-butyl[methoxy(phenyl)methylene]azane oxide；N-tert-butyl-1-methoxy-1-phenylmethanimine oxide
• CAS: 118891-54-6；118949-64-7；135733-53-8
• 化学式: C₁₂H₁₇NO₂
• 分子量: 207.272
• InChiKey: WVQQDGYXHFBVOM-ACCUITESSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.3
• 重原子数：
  15
• 可旋转键数：
  3
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.42
• 拓扑面积：
  38
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  methyl N-(1,1-dimethylethyl)benzenecarboximidate N-oxide 以 丙酮 为溶剂， 生成 N-tert-butyl-1-methoxy-1-phenylmethanimine oxide
  参考文献：
  名称：

  Preferred geometry of unusual nitrones. A facile E-Z isomerization of a C-alkoxynitrone

  摘要：

  A detailed structural study was carried out on C-methoxy-C-aryl-N-tert-butylnitrones (1), members of a relatively new class of compounds (acyclic imidate N-oxides). By H-1 NMR chemical shifts it was shown that 1 exist exclusively as the E isomers in DCCl3 and the Z isomers in acetone-d6. NOE difference spectra confirm these assignments and indicate a preferred conformation in which O-methyl and C-phenyl are more syn periplanar than anti in both cases. Configurations and conformations were similarly determined for C-phenyl-N-tert-butylnitrone (PBN), as well as several nitrone salts. Rates of E to Z isomerization of the phenyl, p-methoxyphenyl, and p-nitrophenyl derivatives of 1 were measured in acetone from 266 to 280 K giving DELTA-H double-ended dagger values of 14.1, 16.9, and 14.2 kcal/mol and DELTA-S double-ended dagger values of -24.3, -14.5, and -25.5 eu, respectively. The unusually low values of DELTA-H double-ended dagger are interpreted in terms of ground-state destabilization due to steric repulsions that are relieved in going to the transition state by rotation about the C = N bond. The large negative DELTA-S double-ended dagger values suggest solvent reorganization to stabilize the charge-separated character of the transition state. Geometry-optimized MNDO calculations are in agreement with conformation results from NOE experiments and predict a large dipole moment difference between E and Z isomers.

  DOI：

  10.1021/jo00022a026
• 作为产物：
  描述：

  在 三乙胺 作用下， 以 氘代氯仿 为溶剂， 生成 methyl N-(1,1-dimethylethyl)benzenecarboximidate N-oxide
  参考文献：
  名称：

  .alpha.-Heteroatom-substituted nitrones. Synthesis and reactions of acyclic .alpha.-alkoxynitrones

  摘要：

  DOI：

  10.1021/jo00268a043

文献信息

• .alpha.-Heteroatom-substituted nitrones. Synthesis and reactions of acyclic .alpha.-alkoxynitrones
  作者：James A. Warshaw、David E. Gallis、Bruce J. Acken、Orestes J. Gonzalez、DeLanson R. Crist

  DOI：10.1021/jo00268a043

  日期：1989.3
• Preferred geometry of unusual nitrones. A facile E-Z isomerization of a C-alkoxynitrone
  作者：David E. Gallis、James A. Warshaw、Bruce J. Acken、DeLanson R. Crist

  DOI：10.1021/jo00022a026

  日期：1991.10

  A detailed structural study was carried out on C-methoxy-C-aryl-N-tert-butylnitrones (1), members of a relatively new class of compounds (acyclic imidate N-oxides). By H-1 NMR chemical shifts it was shown that 1 exist exclusively as the E isomers in DCCl3 and the Z isomers in acetone-d6. NOE difference spectra confirm these assignments and indicate a preferred conformation in which O-methyl and C-phenyl are more syn periplanar than anti in both cases. Configurations and conformations were similarly determined for C-phenyl-N-tert-butylnitrone (PBN), as well as several nitrone salts. Rates of E to Z isomerization of the phenyl, p-methoxyphenyl, and p-nitrophenyl derivatives of 1 were measured in acetone from 266 to 280 K giving DELTA-H double-ended dagger values of 14.1, 16.9, and 14.2 kcal/mol and DELTA-S double-ended dagger values of -24.3, -14.5, and -25.5 eu, respectively. The unusually low values of DELTA-H double-ended dagger are interpreted in terms of ground-state destabilization due to steric repulsions that are relieved in going to the transition state by rotation about the C = N bond. The large negative DELTA-S double-ended dagger values suggest solvent reorganization to stabilize the charge-separated character of the transition state. Geometry-optimized MNDO calculations are in agreement with conformation results from NOE experiments and predict a large dipole moment difference between E and Z isomers.