2,6-dimethyl-4-(2-hydroxy-2-propyl)benzaldehyde

• 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: 2,6-dimethyl-4-(2-hydroxy-2-propyl)benzaldehyde
• 英文别名: 4-(2-Hydroxypropan-2-yl)-2,6-dimethylbenzaldehyde
• 化学式: C₁₂H₁₆O₂
• 分子量: 192.258
• InChiKey: DMLAPWNRKSREIE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.8
• 重原子数：
  14
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.42
• 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：

  2,6-dimethyl-4-(2-hydroxy-2-propyl)benzaldehyde 在 氯化亚砜 作用下， 以 吡啶 、 二氯甲烷 为溶剂， 反应 23.5h， 生成
  参考文献：
  名称：

  Electronic properties of the nitrone substituent. Stabilization of benzylic carbocations

  摘要：

  The nitrone substituent CH=N(O) t-Bu is electron-withdrawing with a Taft sigma (1) value of 0.20. It also retards the solvolysis rate of a cumyl chloride when placed in the meta-position (sigma (+) = 0.20). However, CH=N(O) t-Bu becomes weakly cation stabilizing when placed in the para-position of a cumyl cation (sigma (+) = -0.04). This weak cation stabilization is a result of a conjugative interaction which delocalizes charge and offsets the inductive effect of the nitrone. When the nitrone is placed in the para-position, but then twisted out of conjugation with the aromatic ring by incorporation of flanking 3,5-dimethyl groups, it again retards solvolysis rates. Computational studies (B3LYP/6-31G*) show that the nitrone substituent stabilizes a para-substituted benzyl cation relative to the meta-substituted analog by a conjugative interaction. However, the calculated stabilization greatly overestimates the cation stabilization seen in solvolytic reactions. Copyright (C) 2001 John Wiley & Sons, Ltd.

  DOI：

  10.1002/1099-1395(200102)14:2<97::aid-poc340>3.0.co;2-2

文献信息

• Foiled Conjugation in α-Oximino Carbocations
  作者：Xavier Creary、Ziqi Jiang

  DOI：10.1021/jo960073u

  日期：1996.1.1

  The 4-CHNOCH3 group is a cation-stabilizing group when placed in the para-position of a cumyl cation. The effect of this group on cumyl cations when flanked by adjacent methyl groups has now been determined. Solvolysis rates of 3,5-(CH3)(2)-4-(CHNOCH3)cumyl trifluoroacetates are somewhat slower than that of 3,5-dimethylcumyl trifluoroacetate. This is attributed to steric inhibition of the cation-stabilizing resonance effect of the p-oximino group. In a l-adamantyl system, where an alpha-oximino group has been placed directly adjacent to a developing cationic center, solvolysis rates relative to l-adamantyl mesylate are slowed by a factor of 10(8). This is attributed a cation-destabilizing inductive effect where geometric constraints prevent stabilizing orbital overlap of the cationic center with the adjacent alpha-oximino group. This cation-destabilizing effect fades in the homoadamantyl and the bicyclo[3.3.1]nonyl systems, where rate-retarding effects are 1.6 x 10(4) and 1.5 x 10(2), respectively. The behavior of geometrically constrained alpha-oximino cations parallels that of analogously constrained allylic cations. Computational studies at the HF/6-31G* level indicate that twisting the alpha-oximino group out of planarity with a tertiary cationic center into a perpendicular arrangement decreases stabilization by 21 kcal/mol. These studies suggest that conjugative interactions, and not ground state destabilization, are the most important factors in controlling rates of formation of alpha-oximino cations from mesylates and trifluoroacetates.
• Electronic properties of the nitrone substituent. Stabilization of benzylic carbocations
  作者：Xavier Creary、Kresna Hartandi

  DOI：10.1002/1099-1395(200102)14:2<97::aid-poc340>3.0.co;2-2

  日期：2001.2

  The nitrone substituent CH=N(O) t-Bu is electron-withdrawing with a Taft sigma (1) value of 0.20. It also retards the solvolysis rate of a cumyl chloride when placed in the meta-position (sigma (+) = 0.20). However, CH=N(O) t-Bu becomes weakly cation stabilizing when placed in the para-position of a cumyl cation (sigma (+) = -0.04). This weak cation stabilization is a result of a conjugative interaction which delocalizes charge and offsets the inductive effect of the nitrone. When the nitrone is placed in the para-position, but then twisted out of conjugation with the aromatic ring by incorporation of flanking 3,5-dimethyl groups, it again retards solvolysis rates. Computational studies (B3LYP/6-31G*) show that the nitrone substituent stabilizes a para-substituted benzyl cation relative to the meta-substituted analog by a conjugative interaction. However, the calculated stabilization greatly overestimates the cation stabilization seen in solvolytic reactions. Copyright (C) 2001 John Wiley & Sons, Ltd.