p-methyl-N-methylbenzohydroxamate | 53875-16-4

• 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: p-methyl-N-methylbenzohydroxamate
• 英文别名: N,4-dimethyl-N-oxidobenzamide
• CAS: 53875-16-4
• 化学式: C₉H₁₀NO₂
• 分子量: 164.184
• InChiKey: OOQDJLCHSBEQGD-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.2
• 重原子数：
  12
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.22
• 拓扑面积：
  43.4
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  p-methyl-N-methylbenzohydroxamate 、 4-硝基苯基乙酸酯 以 水 、 乙腈 为溶剂， 生成 4-硝基苯酚阴离子 、
  参考文献：
  名称：

  Effect of Solvent on the α-Effect:  Nucleophilic Substitution Reactions of p-Nitrophenyl Acetate with m-Chlorophenoxide and Benzohydroxamates in MeCN−H₂O Mixtures of Varying Compositions

  摘要：

  Second-order rate constants have been measured spectrophotometrically for the reactions of p-nitrophenyl acetate (PNPA) with three alpha-effect nucleophiles, benzohydroxamate (BHA(-)), p-methylbenzohydroxamate (MBHA(-)), and p-methyl-N-methylbenzohydroxamate (M(2)BHA(-)), and a corresponding normal nucleophile, m-chlorophenoxide (CIPhO-), in MeCN-H2O mixtures of varying compositions at 25.0 degrees C. The reactivity of CIPhO- and M(2)BHA(-) toward PNPA decreases upon additions of MeCN into the reaction medium up to near 30-40 mol % MeCN and is followed by a gradual increase upon further additions of MeCN. BHA(-) and MBHA(-) also exhibit initial rate decreases upon the addition of MeCN up to near 40 mol % MeCN. However, unlike the CIPhO- and M(2)BKA(-) systems, the rate enhancement beyond 40 mol % MeCN is negligible for the BHA(-) and MBHA(-) systems. The present benzohydroxamates exert a large alpha-effect H2O. Interestingly, BHA(-) and MBHA(-) show a decreasing alpha-effect trend with increasing mol % MeCN, while M(2)BHA(-) exhibits an increasing alpha-effect trend, indicating that the magnitude of the alpha-effect is significantly solvent dependent. Based on the results of the kinetic study and relative basicity measurements, the decreasing alpha-effect trend shown by BHA(-) and MBHA(-) has been attributed to an equilibrium shift of these hydroxamates (I) toward their isomeric structures (II or III) upon the addition of MeCN. The solvent dependent alpha-effect has led a conclusion that the solvent effect on the alpha-effect is significant; however, the ground state contribution is not solely responsible for the alpha-effect in the present system.

  DOI：

  10.1021/jo970665s