3-allyloxy-4,4,5,5-tetramethyl-3-phenyl-1,2-dioxolane

• 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: 3-allyloxy-4,4,5,5-tetramethyl-3-phenyl-1,2-dioxolane
• 英文别名: 3,3,4,4-Tetramethyl-5-phenyl-5-prop-2-enoxydioxolane
• 化学式: C₁₆H₂₂O₃
• 分子量: 262.349
• InChiKey: UMMKRCLJAPYOQX-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.6
• 重原子数：
  19
• 可旋转键数：
  4
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  27.7
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  3-allyloxy-4,4,5,5-tetramethyl-3-phenyl-1,2-dioxolane 以 氘代苯 为溶剂， 生成 频哪酮 、 苯甲酸烯丙酯
  参考文献：
  名称：

  Synthesis and Thermolysis of Ketal Derivatives of 3-Hydroxy-1,2-dioxolanes

  摘要：

  3-[(Trimethylsilyl)oxy]-3,4,4,5-tetramethyl-5-phenyl-1,2-dioxolane (2), 3-methoxy-3,4,4,5-tetra-methyl-5-phenyl-1,2-dioxolane (3), and 3-acetoxy-3,4,4,5-tetramethyl-5-phenyl-1 (4) were synthesized from the corresponding 3-hydroxy-1,2-dioxolane (1a) under basic conditions. 3-Acetoxy-4,4-dimethyl-3,5,5-triphenyl-1,2-dioxolane (5) was also synthesized via this approach. Under acidic conditions, 3-hydroxy-1,2-dioxolane la underwent quantitative decomposition to phenol and 3,3-dimethyl-2,4-pentanedione. This competing degradation was dependent on the nature of the substituents at position-5. Methyl groups at position-5 slowed the degradative rearrangement whereas phenyl groups favored it. 3-Methoxy- and 3-(allyloxy)-4,4,5,5-tetramethyl-3-pheny dioxolanes (6, 7) were synthesized under acidic conditions from the appropriate 1,2-dioxolane precursors and the corresponding alcohols. At 60 degrees C, derivatized 1,2-dioxolanes 2-7 were found to be more stable than the corresponding 3-hydroxy-1, 2-dioxolanes. The first order rate constants for the thermolysis of 1,2-dioxolanes 2-7 were determined. Product studies showed that thermolysis of 2-5 yielded pairs of ketones and derivatized carboxylic acids. In addition to R-group migration products, an acetoxy migration product was observed for the thermolysis of 4. Thermolysis of 6 at 60 degrees C in benzene yielded methyl benzoate and pinacolone, quantitatively. Thermolysis of 7 yielded products analogous to those for 6. No evidence for internal trapping of radicals by the carbon-carbon double bond of the allyloxy group in 7 was found. The thermolyis appeared to proceed with peroxy bond homolysis as the rate-determining step. Subsequent beta-scissions of the intermediate 1,5-oxygen diradical with interesting rearrangements that show a high preference for alkyl vs phenyl migration account for the observed product distributions. The results suggest that the beta-scission/ rearrangement mechanism may not be concerted but rather stepwise to yield 1,3-diradical and carbonyl fragments.

  DOI：

  10.1021/jo00101a030
• 作为产物：
  描述：

  3-hydroxy-4,4,5,5-tetramethyl-3-phenyl-1,2-dioxolane 在 盐酸 、 磷酸酐 作用下， 以 氯仿 为溶剂， 反应 4.5h， 生成 3-allyloxy-4,4,5,5-tetramethyl-3-phenyl-1,2-dioxolane
  参考文献：
  名称：

  Synthesis and Thermolysis of Ketal Derivatives of 3-Hydroxy-1,2-dioxolanes

  摘要：

  3-[(Trimethylsilyl)oxy]-3,4,4,5-tetramethyl-5-phenyl-1,2-dioxolane (2), 3-methoxy-3,4,4,5-tetra-methyl-5-phenyl-1,2-dioxolane (3), and 3-acetoxy-3,4,4,5-tetramethyl-5-phenyl-1 (4) were synthesized from the corresponding 3-hydroxy-1,2-dioxolane (1a) under basic conditions. 3-Acetoxy-4,4-dimethyl-3,5,5-triphenyl-1,2-dioxolane (5) was also synthesized via this approach. Under acidic conditions, 3-hydroxy-1,2-dioxolane la underwent quantitative decomposition to phenol and 3,3-dimethyl-2,4-pentanedione. This competing degradation was dependent on the nature of the substituents at position-5. Methyl groups at position-5 slowed the degradative rearrangement whereas phenyl groups favored it. 3-Methoxy- and 3-(allyloxy)-4,4,5,5-tetramethyl-3-pheny dioxolanes (6, 7) were synthesized under acidic conditions from the appropriate 1,2-dioxolane precursors and the corresponding alcohols. At 60 degrees C, derivatized 1,2-dioxolanes 2-7 were found to be more stable than the corresponding 3-hydroxy-1, 2-dioxolanes. The first order rate constants for the thermolysis of 1,2-dioxolanes 2-7 were determined. Product studies showed that thermolysis of 2-5 yielded pairs of ketones and derivatized carboxylic acids. In addition to R-group migration products, an acetoxy migration product was observed for the thermolysis of 4. Thermolysis of 6 at 60 degrees C in benzene yielded methyl benzoate and pinacolone, quantitatively. Thermolysis of 7 yielded products analogous to those for 6. No evidence for internal trapping of radicals by the carbon-carbon double bond of the allyloxy group in 7 was found. The thermolyis appeared to proceed with peroxy bond homolysis as the rate-determining step. Subsequent beta-scissions of the intermediate 1,5-oxygen diradical with interesting rearrangements that show a high preference for alkyl vs phenyl migration account for the observed product distributions. The results suggest that the beta-scission/ rearrangement mechanism may not be concerted but rather stepwise to yield 1,3-diradical and carbonyl fragments.

  DOI：

  10.1021/jo00101a030

文献信息

• Baumstark A. L., Vasquez P. C., Chen Y.-X., J. Org. Chem, 59 (1994) N 22, S 6692-6696
  作者：Baumstark A. L., Vasquez P. C., Chen Y.-X.

  DOI：——

  日期：——
• Synthesis and Thermolysis of Ketal Derivatives of 3-Hydroxy-1,2-dioxolanes
  作者：A. L. Baumstark、P. C. Vasquez、Y.-X. Chen

  DOI：10.1021/jo00101a030

  日期：1994.11

  3-[(Trimethylsilyl)oxy]-3,4,4,5-tetramethyl-5-phenyl-1,2-dioxolane (2), 3-methoxy-3,4,4,5-tetra-methyl-5-phenyl-1,2-dioxolane (3), and 3-acetoxy-3,4,4,5-tetramethyl-5-phenyl-1 (4) were synthesized from the corresponding 3-hydroxy-1,2-dioxolane (1a) under basic conditions. 3-Acetoxy-4,4-dimethyl-3,5,5-triphenyl-1,2-dioxolane (5) was also synthesized via this approach. Under acidic conditions, 3-hydroxy-1,2-dioxolane la underwent quantitative decomposition to phenol and 3,3-dimethyl-2,4-pentanedione. This competing degradation was dependent on the nature of the substituents at position-5. Methyl groups at position-5 slowed the degradative rearrangement whereas phenyl groups favored it. 3-Methoxy- and 3-(allyloxy)-4,4,5,5-tetramethyl-3-pheny dioxolanes (6, 7) were synthesized under acidic conditions from the appropriate 1,2-dioxolane precursors and the corresponding alcohols. At 60 degrees C, derivatized 1,2-dioxolanes 2-7 were found to be more stable than the corresponding 3-hydroxy-1, 2-dioxolanes. The first order rate constants for the thermolysis of 1,2-dioxolanes 2-7 were determined. Product studies showed that thermolysis of 2-5 yielded pairs of ketones and derivatized carboxylic acids. In addition to R-group migration products, an acetoxy migration product was observed for the thermolysis of 4. Thermolysis of 6 at 60 degrees C in benzene yielded methyl benzoate and pinacolone, quantitatively. Thermolysis of 7 yielded products analogous to those for 6. No evidence for internal trapping of radicals by the carbon-carbon double bond of the allyloxy group in 7 was found. The thermolyis appeared to proceed with peroxy bond homolysis as the rate-determining step. Subsequent beta-scissions of the intermediate 1,5-oxygen diradical with interesting rearrangements that show a high preference for alkyl vs phenyl migration account for the observed product distributions. The results suggest that the beta-scission/ rearrangement mechanism may not be concerted but rather stepwise to yield 1,3-diradical and carbonyl fragments.