1-(4,5-dichloro-2-hydroxyphenyl)propan-1-one | 288401-09-2

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 1-(4,5-dichloro-2-hydroxyphenyl)propan-1-one
• 英文别名: 4'',5''-Dichloro-2''-hydroxypropiophenone
• CAS: 288401-09-2
• 化学式: C₉H₈Cl₂O₂
• 分子量: 219.067
• InChiKey: WTIDMFFQSYNHMT-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.5
• 重原子数：
  13
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.22
• 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：

  1-(4,5-dichloro-2-hydroxyphenyl)propan-1-one 在 sodium hexamethyldisilazane 、 N-氟苯磺酰胺 作用下， 以 四氢呋喃 为溶剂， 反应 1.5h， 以69%的产率得到1-(4,5-dichloro-2-hydroxyphenyl)-2-fluoropropan-1-one
  参考文献：
  名称：

  Rate of Enolate Formation Is Not Very Sensitive to the Hydrogen Bonding Ability of Donors to Carboxyl Oxygen Lone Pair Acceptors; A Ramification of the Principle of Non-Perfect Synchronization for General-Base-Catalyzed Enolate Formation

  摘要：

  Two series of structures (1 and 2) possessing intramolecular hydrogen bonds to the lone-pair electrons of carbonyl oxygens have been examined to reveal the influence of the pK(a) of the hydrogen-bond donor on the rate of general -base -catalyzed enolate formation. The geometry of the hydrogen bonds is well accepted to be appropriate for intramolecular hydrogen-bond formation. Yet, as revealed by Bronsted plots, both series show very little dependence of the rate of enolate formation on the hydrogen-bond donor ability. The intramolecular hydrogen bonds give rate enhancements only on the order of 10-100-fold, and corrected Bronsted alpha-values are slightly below 0.1. The results can be understood by interpreting them in light of the Principle of Non-Perfect Synchronization. The results are consistent with the proton transfer occurring through an asynchronous transition state with the developing negative charge localized on carbon. We postulate that catalysts of enolate formation will be most effective if the binding groups are focused on stabilizing negative charge that is forming on the enolate carbon rather than on the enolate oxygen.

  DOI：

  10.1021/ja0306011
• 作为产物：
  描述：

  3,4-二氯苯酚 在 sodium hydroxide 、 三氯化铝 作用下， 以 乙腈 为溶剂， 反应 20.25h， 生成 1-(4,5-dichloro-2-hydroxyphenyl)propan-1-one
  参考文献：
  名称：

  Rate of Enolate Formation Is Not Very Sensitive to the Hydrogen Bonding Ability of Donors to Carboxyl Oxygen Lone Pair Acceptors; A Ramification of the Principle of Non-Perfect Synchronization for General-Base-Catalyzed Enolate Formation

  摘要：

  Two series of structures (1 and 2) possessing intramolecular hydrogen bonds to the lone-pair electrons of carbonyl oxygens have been examined to reveal the influence of the pK(a) of the hydrogen-bond donor on the rate of general -base -catalyzed enolate formation. The geometry of the hydrogen bonds is well accepted to be appropriate for intramolecular hydrogen-bond formation. Yet, as revealed by Bronsted plots, both series show very little dependence of the rate of enolate formation on the hydrogen-bond donor ability. The intramolecular hydrogen bonds give rate enhancements only on the order of 10-100-fold, and corrected Bronsted alpha-values are slightly below 0.1. The results can be understood by interpreting them in light of the Principle of Non-Perfect Synchronization. The results are consistent with the proton transfer occurring through an asynchronous transition state with the developing negative charge localized on carbon. We postulate that catalysts of enolate formation will be most effective if the binding groups are focused on stabilizing negative charge that is forming on the enolate carbon rather than on the enolate oxygen.

  DOI：

  10.1021/ja0306011

文献信息

• Letcher, Roy M., Journal of Chemical Research, Miniprint, 1989, # 12, p. 2901 - 2929
  作者：Letcher, Roy M.

  DOI：——

  日期：——
• Rate of Enolate Formation Is Not Very Sensitive to the Hydrogen Bonding Ability of Donors to Carboxyl Oxygen Lone Pair Acceptors; A Ramification of the Principle of Non-Perfect Synchronization for General-Base-Catalyzed Enolate Formation
  作者：Zhenlin Zhong、Timothy S. Snowden、Michael D. Best、Eric V. Anslyn

  DOI：10.1021/ja0306011

  日期：2004.3.1

  Two series of structures (1 and 2) possessing intramolecular hydrogen bonds to the lone-pair electrons of carbonyl oxygens have been examined to reveal the influence of the pK(a) of the hydrogen-bond donor on the rate of general -base -catalyzed enolate formation. The geometry of the hydrogen bonds is well accepted to be appropriate for intramolecular hydrogen-bond formation. Yet, as revealed by Bronsted plots, both series show very little dependence of the rate of enolate formation on the hydrogen-bond donor ability. The intramolecular hydrogen bonds give rate enhancements only on the order of 10-100-fold, and corrected Bronsted alpha-values are slightly below 0.1. The results can be understood by interpreting them in light of the Principle of Non-Perfect Synchronization. The results are consistent with the proton transfer occurring through an asynchronous transition state with the developing negative charge localized on carbon. We postulate that catalysts of enolate formation will be most effective if the binding groups are focused on stabilizing negative charge that is forming on the enolate carbon rather than on the enolate oxygen.