((4R,4aS,7aS)-1,1-Dioxo-octahydro-1λ⁶-cyclopenta[b]thiopyran-4-yloxy)-trimethyl-silane | 134451-87-9

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 硫杂环戊烷
• 英文名称: ((4R,4aS,7aS)-1,1-Dioxo-octahydro-1λ⁶-cyclopenta[b]thiopyran-4-yloxy)-trimethyl-silane
• 英文别名: [(4R,4aS,7aS)-1,1-dioxo-2,3,4,4a,5,6,7,7a-octahydrocyclopenta[b]thiopyran-4-yl]oxy-trimethylsilane
• CAS: 134451-87-9
• 化学式: C₁₁H₂₂O₃SSi
• 分子量: 262.445
• InChiKey: BWMCAWITVWDIPO-AXFHLTTASA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.19
• 重原子数：
  16
• 可旋转键数：
  2
• 环数：
  2.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  51.8
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  (E)-thiacyclonon-4-ene 在 potassium tert-butylate 、 三乙胺 、 间氯过氧苯甲酸 作用下， 以 二氯甲烷 为溶剂， 反应 10.25h， 生成 ((4R,4aS,7aS)-1,1-Dioxo-octahydro-1λ⁶-cyclopenta[b]thiopyran-4-yloxy)-trimethyl-silane
  参考文献：
  名称：

  Desilylative transannular cyclization of nine-membered .alpha.-silyl (E)-.gamma.-epoxy sulfones

  摘要：

  Anionic desilylation of alpha-silylated (E)-4,5-epoxythiacyclononane 1,1-dioxides results in formation of transannular cyclization products whose distribution is independent of the stereochemistry of the starting material. Unlike the species formed by direct BuLi metalation,1 the intermediate arising from the 9-sily regioisomer rapidly and indiscriminately attacks either epoxidic carbon forming both cis- and trans-joined bicyclic products. This lack of selectivity suggests the reactive intermediate is not a hypervalent silicon species, but is more likely a carbanion which, being associated to a large cation (K+ or Bu4N+) is less discriminating than that arising from BuLi metalation. The intermediate formed by desilylation of the 2-silyl regioisomer appears to cyclize relatively slowly, such that transfer of the carbanionic functionality from C-2 to C-9 becomes competitive with cyclization. With this substrate an unexpected phenomenon has emerged, namely that t-BuOK may act as a base or a desilylating agent depending on the temperature.

  DOI：

  10.1021/jo00031a024

文献信息

• Medium-ring .gamma.-epoxy sulfones. Regio- and stereochemistry of the butyllithium-promoted transannular epoxide ring opening
  作者：Vanda Cere、Claudio Paolucci、Salvatore Pollicino、Edda Sandri、Antonino Fava

  DOI：10.1021/jo00014a035

  日期：1991.7

  Cyclic 8- and 9-membered E and Z gamma-epoxy sulfones yield bicyclic hydroxy sulfones stereospecifically upon treatment with BuLi in THF. The distribution of regioisomeric products markedly depends on the metalation mode, portionwise or at once. This suggests that the metal/proton exchange between the two positions alpha to the sulfone function is slow, relative to transannular cyclization, under conditions of complete metalation, but becomes fast in the presence of unmetalated sulfone (probably acting as a H+-transfer agent). The product distribution also depends, though to a lesser extent, on temperature, perhaps in relation to changes in the aggregation of the organolithium intermediate. An unexpected phenomenon was observed with the 8-membered Z epoxy sulfone at -70-degrees-C, where the time dependence of the transannular cyclization is consistent with an equilibrium being reached at 2/3 conversion. However, at -40-degrees-C or higher the reaction proceeds to completion without difficulty. A low-temperature metastable equilibrium is suggested involving some kind of aggregate of the lithio sulfone with the lithioalkoxide product.