cis-3-bromo-4-hydroxytetrahydrothiopyran

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 噻烷
• 英文名称: cis-3-bromo-4-hydroxytetrahydrothiopyran
• 英文别名: (3S,4S)-3-bromothian-4-ol
• 化学式: C₅H₉BrOS
• 分子量: 197.096
• InChiKey: FVKXPGQLIGGDFE-UHNVWZDZSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.2
• 重原子数：
  8
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  45.5
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  5-(benzylthio)-3-hydroxy-1-pentene 在 溴 作用下， 以 氘代氯仿 为溶剂， 生成 cis-3-bromo-4-hydroxytetrahydrothiopyran 、 (2R,3S)-2-Bromomethyl-tetrahydro-thiophen-3-ol
  参考文献：
  名称：

  Regiochemical and stereochemical studies on halocyclization reactions of unsaturated sulfides

  摘要：

  The regiochemistry and stereochemistry for the halocyclization reactions of unsaturated benzyl sulfides have been examined as a function of tether length, type of unsaturation (carbon-carbon double bond versus carbon-carbon triple bond), substituents, and halogenating agent. Alkenyl sulfides were found to react with iodine or bromine at room temperature to give five-membered ring cycloadducts exclusively over those having four-membered rings, while for larger systems, six-membered ring products are formed preferentially over their five-membered ring isomers and exclusively over the seven-membered ring adducts. The endo- versus exo-regioselectivity of these alkenyl sulfide ring closures most likely reflects the difference in thermodynamic stabilities of the beta-halo sulfide cycloadducts, which are able to equilibrate via a common episulfonium intermediate. The efficiency of the cyclization process markedly drops off for these alkenyl sulfides as the tether length increases beyond four intervening carbon centers. Thus, while the halogenations of 3-butenyl sulfides and 4-pentenyl sulfides give high yields of cycloadducts, those of 5-hexenyl sulfides afford only small amounts of cyclized products and large quantities of acyclic dibromides. Conversely the reactions of acetylenic sulfides with iodine give uniformly high yields and regiochemical control regardless of the tether length. Thus, 3-butynyl and 4-pentynyl sulfides cyclize cleanly to the five-membered ring while 5-hexynyl sulfides give exclusively the six-membered ring, The products arising from these alkynyl sulfide ring closures are believed to be formed under kinetic control. The methodology has been applied to the synthesis of unusual bicyclic beta-lactams related to the penicillin family of antibiotics.

  DOI：

  10.1021/jo00125a038

文献信息

• Regiochemical and stereochemical studies on halocyclization reactions of unsaturated sulfides
  作者：Xiao-Feng Ren、Edward Turos、Charles H. Lake、Melvyn Rowen Churchill

  DOI：10.1021/jo00125a038

  日期：1995.10

  The regiochemistry and stereochemistry for the halocyclization reactions of unsaturated benzyl sulfides have been examined as a function of tether length, type of unsaturation (carbon-carbon double bond versus carbon-carbon triple bond), substituents, and halogenating agent. Alkenyl sulfides were found to react with iodine or bromine at room temperature to give five-membered ring cycloadducts exclusively over those having four-membered rings, while for larger systems, six-membered ring products are formed preferentially over their five-membered ring isomers and exclusively over the seven-membered ring adducts. The endo- versus exo-regioselectivity of these alkenyl sulfide ring closures most likely reflects the difference in thermodynamic stabilities of the beta-halo sulfide cycloadducts, which are able to equilibrate via a common episulfonium intermediate. The efficiency of the cyclization process markedly drops off for these alkenyl sulfides as the tether length increases beyond four intervening carbon centers. Thus, while the halogenations of 3-butenyl sulfides and 4-pentenyl sulfides give high yields of cycloadducts, those of 5-hexenyl sulfides afford only small amounts of cyclized products and large quantities of acyclic dibromides. Conversely the reactions of acetylenic sulfides with iodine give uniformly high yields and regiochemical control regardless of the tether length. Thus, 3-butynyl and 4-pentynyl sulfides cyclize cleanly to the five-membered ring while 5-hexynyl sulfides give exclusively the six-membered ring, The products arising from these alkynyl sulfide ring closures are believed to be formed under kinetic control. The methodology has been applied to the synthesis of unusual bicyclic beta-lactams related to the penicillin family of antibiotics.