2,2,6,6-tetraethoxy-2,6-disilaoxacyclohexane

• 分子结构分类: 有机化合物 - 有机金属化合物 - 有机类金属化合物
• 英文名称: 2,2,6,6-tetraethoxy-2,6-disilaoxacyclohexane
• 英文别名: 2,2,6,6-Tetraethoxy-1,2,6-oxadisilinane
• 化学式: C₁₁H₂₆O₅Si₂
• 分子量: 294.495
• InChiKey: KKKPFJFSFMOWLR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.43
• 重原子数：
  18
• 可旋转键数：
  8
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  46.2
• 氢给体数：
  0
• 氢受体数：
  5

反应信息

• 作为产物：
  描述：

  烯丙基三乙氧基硅烷 在 盐酸 、 dihydrogen hexachloroplatinate 、 水 作用下， 以 乙醇 、 苯 为溶剂， 反应 48.0h， 生成 2,2,6,6-tetraethoxy-2,6-disilaoxacyclohexane
  参考文献：
  名称：

  Cyclization Phenomena in the Sol−Gel Polymerization of α,ω-Bis(triethoxysilyl)alkanes and Incorporation of the Cyclic Structures into Network Silsesquioxane Polymers

  摘要：

  Intramolecular cyclizations during acid-catalyzed sol-gel polymerizations of alpha,omega-bis(triethoxysilyl)-alkanes substantially lengthen gel times for monomers with ethylene (1), propylene (2), and butylene (3) bridging groups. These cyclization reactions were found, using mass spectrometry and Si-29 NMR spectroscopy, to lead preferentially to monomeric and dimeric products based on six- and seven-membered disilsesquioxane rings. 1,2-Bis(triethoxysilyl)ethane (1) reacts under acidic conditions to give a bicyclic dimer (5) that is composed of two annelated seven-membered rings. Under the same conditions, 1,3-bis(triethoxysilyl)propane (2), 1,4-bis(triethoxysilyl)butane (3), and Z-1,4-bis(triethoxysilyl)but-2-ene (10) undergo an intramolecular condensation reaction to give the six- and seven-membered cyclic disilsesquioxanes 6, 7, and 11. Subsequently, these cyclic monomers slowly react to form the tricyclic dimers 8, 9, and 12. With NaOH as polymerization catalyst, these cyclic silsesquioxanes readily reacted to afford gels that were shown by CP MAS Si-29 NMR and infrared spectroscopies to retain some cyclic structures. Comparison of the porosity and microstructure of xerogels prepared from the cyclic monomers 6 and 7 with those of gels prepared directly from their acyclic precursors 2 and 3 indicates that the final pore structure of the xerogels is markedly dependent on the nature of the precursor. In addition, despite the fact that the monomeric cyclic disilsesquioxane species cannot be isolated from 1-3 under basic conditions due to their rapid rate of gelation, spectroscopic techniques also detected the presence of the cyclic structures in the resulting polymeric gels.

  DOI：

  10.1021/ja982751v

文献信息

• Intramolecular Condensation Reactions of α,ω-Bis(triethoxysilyl)alkanes. Formation of Cyclic Disilsesquioxanes
  作者：Douglas A. Loy、Joseph P. Carpenter、Sharon A. Myers、Roger A. Assink、James H. Small、John Greaves、Kenneth J. Shea

  DOI：10.1021/ja961409k

  日期：1996.1.1

  alkylene-bridging groups had a pronounced effect on the competition between cyclization and polymerization of alpha},omega}-bis(triethoxysilyl)alkanes and on the formation of polymeric gels. While the intramolecular reaction clearly slows gelation, the cyclic disilsesquioxanes are still tetrafunctional monomers theoretically capable of forming polymeric gels. If the ring structures, which bear a striking resemblence

  在本文中，我们使用质谱和 sup 29}Si NMR 光谱发现亚烷基桥连基团的长度对 alpha},omega}-bis(triethoxysilyl )烷烃和聚合物凝胶的形成。虽然分子内反应明显减缓了凝胶化，但环状二倍半硅氧烷仍然是理论上能够形成聚合物凝胶的四官能单体。如果通过聚合保留与碳水化合物惊人相似的环结构，则所得聚（环状二倍半硅氧烷）凝胶可能与支链或交联碳水化合物（如纤维素或壳聚糖）具有结构相似性。在碱催化的溶胶-凝胶聚合条件下，3 和 4（六元和七元环状二倍半硅氧烷、分别）快速反应以产生具有显着开环的凝胶，这由 sup 29}Si 化学位移在固态 (CP MAS) NMR 光谱中确定。然而，在酸性条件下制备的凝胶表明聚合物中保留了部分或全部环状二倍半硅氧烷官能团。13 参考，1 图。
• Cyclization Phenomena in the Sol−Gel Polymerization of α,ω-Bis(triethoxysilyl)alkanes and Incorporation of the Cyclic Structures into Network Silsesquioxane Polymers
  作者：Douglas A. Loy、Joseph P. Carpenter、Todd M. Alam、Raef Shaltout、Peter K. Dorhout、John Greaves、James H. Small、Kenneth J. Shea

  DOI：10.1021/ja982751v

  日期：1999.6.1

  Intramolecular cyclizations during acid-catalyzed sol-gel polymerizations of alpha,omega-bis(triethoxysilyl)-alkanes substantially lengthen gel times for monomers with ethylene (1), propylene (2), and butylene (3) bridging groups. These cyclization reactions were found, using mass spectrometry and Si-29 NMR spectroscopy, to lead preferentially to monomeric and dimeric products based on six- and seven-membered disilsesquioxane rings. 1,2-Bis(triethoxysilyl)ethane (1) reacts under acidic conditions to give a bicyclic dimer (5) that is composed of two annelated seven-membered rings. Under the same conditions, 1,3-bis(triethoxysilyl)propane (2), 1,4-bis(triethoxysilyl)butane (3), and Z-1,4-bis(triethoxysilyl)but-2-ene (10) undergo an intramolecular condensation reaction to give the six- and seven-membered cyclic disilsesquioxanes 6, 7, and 11. Subsequently, these cyclic monomers slowly react to form the tricyclic dimers 8, 9, and 12. With NaOH as polymerization catalyst, these cyclic silsesquioxanes readily reacted to afford gels that were shown by CP MAS Si-29 NMR and infrared spectroscopies to retain some cyclic structures. Comparison of the porosity and microstructure of xerogels prepared from the cyclic monomers 6 and 7 with those of gels prepared directly from their acyclic precursors 2 and 3 indicates that the final pore structure of the xerogels is markedly dependent on the nature of the precursor. In addition, despite the fact that the monomeric cyclic disilsesquioxane species cannot be isolated from 1-3 under basic conditions due to their rapid rate of gelation, spectroscopic techniques also detected the presence of the cyclic structures in the resulting polymeric gels.