1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-1,2-C-(dibromomethylene)-D-glycero-D-gulo-hexitol

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-1,2-C-(dibromomethylene)-D-glycero-D-gulo-hexitol
• 英文别名: (1S,3R,4S,5R,6R)-7,7-dibromo-4,5-bis(phenylmethoxy)-3-(phenylmethoxymethyl)-2-oxabicyclo[4.1.0]heptane
• 化学式: C₂₈H₂₈Br₂O₄
• 分子量: 588.336
• InChiKey: XBNHVWYWTSLHGQ-ACFIUOAZSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.7
• 重原子数：
  34
• 可旋转键数：
  10
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.36
• 拓扑面积：
  36.9
• 氢给体数：
  0
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-1,2-C-(dibromomethylene)-D-glycero-D-gulo-hexitol 在 silver(I) acetate 作用下， 以 甲苯 为溶剂， 反应 22.0h， 以38%的产率得到1,7-anhydro-4,5-di-O-benzyl-2-bromo-2,3-dideoxy-β-D-arabinohept-2-enoseptanose
  参考文献：
  名称：

  从1,2- 2-C-支链吡喃糖苷和oxepines发散合成宝石-dibromocyclopropyl碳水化合物

  摘要：

  开环的1,2-（宝石二溴）环丙基碳水化合物由两种不同的模式导致要么2- Ç - （溴亚甲基）吡喃糖苷（使用碱）或2- bromooxepines（使用银盐），如我们之前显示一d -glucal衍生环丙烷。碱促进的开环扩展到涵盖其他醇，硫醇和胺亲核试剂以及非对映异构体环丙烷前体。2- C-（溴亚甲基）吡喃糖苷的交叉偶联导致扩展的2- C-支化吡喃糖苷。描述了在各种醇的存在下银促进的环丙基碳水化合物的环扩环。生成的苄基2-溴氧杂环丁烷的交叉偶联得到2- C取代的奥沙平。

  DOI：

  10.1016/j.tet.2014.06.069
• 作为产物：
  描述：

  3,4,6-三苄氧基-D-葡萄烯糖 、 三溴甲烷 在 potassium fluoride 、 sodium hydroxide 、 苄基三乙基氯化铵 作用下， 反应 48.0h， 以79%的产率得到1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-1,2-C-(dibromomethylene)-D-glycero-D-gulo-hexitol
  参考文献：
  名称：

  Synthesis and Reactions of 1,2-Cyclopropanated Sugars

  摘要：

  Diastereospecific cyclopropanation of glycals 1, 2, 3, 4, and 41 was carried out using either dihalocarbene addition or zinc-carbenoid addition to yield 1,2-cyclopropanated sugars. Dichloro- and dibromocarbenes added stereoselectively anti to the C-3 benzyloxy group, whereas (under Simmons-Smith conditions) the cyclopropanes were formed syn to the same substituent. The reactions of these 1,2-cyclopropanated sugars to provide either ring expanded glycosides or C-2-branched chain glycosides were explored. Solvolytic ring expansion of 1,2-dibromocyclopropanated sugars with K2CO3 in refluxing methanol yielded the corresponding chiral oxepins 20-22. Electrophilic ring openings of parent cyclopropanes (14 and 17 derived from glucal 1) were carried out with different electrophiles to give functionalized 2-deoxy-2-C-branched chain glycosides. The ring openings of 14 in different solvents resulted in both alpha- and beta-anomers, whereas 17 gave exclusively the alpha-anomer.

  DOI：

  10.1021/jo970948k

文献信息

• Mechanistic Studies on the Base-Promoted Ring Opening of Glycal-Derived <i>gem</i>-Dibromocyclopropanes
  作者：Romain J. Lepage、Peter W. Moore、Russell J. Hewitt、Paul H. Teesdale-Spittle、Elizabeth H. Krenske、Joanne E. Harvey

  DOI：10.1021/acs.joc.1c02366

  日期：2022.1.7

  deprotonation step. The roles of the formed alcohol molecule and the bulk (co)solvent are demonstrated by isotope-labeling studies performed with deuterated solvents. The acid-promoted isomerization of the E-bromoalkene product into the corresponding Z-bromoalkene is also described. The mechanistic knowledge gained in this investigation sheds light on the unusual chemistry of this system and facilitates its future

  在存在亲核碱的情况下，衍生自d -glycals的稠环偕二溴环丙烷进行开环以产生 2-deoxy-2-( E - bromethylene)glycosides。环外环丙烷键的这种断裂与发生环内键断裂的更常见的银促进的扩环反应形成对比。报告了实验和理论研究，这些研究提供了对反应机理及其对E的动力学选择性的起源的见解-配置溴烯烃产品。密度泛函理论计算 (M06-2X) 预测该反应开始于醇盐诱导的 HBr 从二溴环丙烷中消除以形成溴环丙烯。然后开环得到构型稳定的两性离子（氧代碳鎓阳离子/乙烯基碳负离子）中间体，该中间体经过亲核加成和质子化得到溴烯烃。在最后一步中，质子有两种相互竞争的来源：一种是醇（共）溶剂，另一种是在初始去质子化步骤中产生的醇分子。用氘代溶剂进行的同位素标记研究证明了形成的醇分子和本体（共）溶剂的作用。E的酸促进异构化还描述了将-溴代烯烃产物转化为相应的Z-溴代烯烃。在这项研
• Synthesis of C-furanosides from a<scp>d</scp>-glucal-derived cyclopropane through a ring-expansion/ring-contraction sequence
  作者：Russell J. Hewitt、Joanne E. Harvey

  DOI：10.1039/c0cc02244f

  日期：——

  gem-Dibromocyclopropane 1, prepared from tri-O-benzyl-D-glucal, undergoes thermal and silver-promoted ring expansion in the presence of alcohols to give substituted oxepines. With further heating, ring contraction to highly substituted tetrahydrofurans follows. These represent C-furanosides, potentially useful as precursors to C-nucleosides and other carbohydrate mimics.

  偕二溴环丙烷 1，由三-O-苄基-D-葡萄糖制备，在醇存在下经历热和银促进的环扩展，得到取代的氧杂环庚烷。随着进一步加热，环收缩成高度取代的四氢呋喃。这些代表 C-呋喃糖苷，可能用作 C-核苷和其他碳水化合物模拟物的前体。
• Synthesis of Oxepines and 2-Branched Pyranosides from a <scp>d</scp>-Glucal-Derived <i>gem</i>-Dibromo-1,2-cyclopropanated Sugar
  作者：Russell J. Hewitt、Joanne E. Harvey

  DOI：10.1021/jo902306a

  日期：2010.2.5

  The conversion of cyclopropane-fused carbohydrates into oxepines is an attractive method for accessing diverse members of the septanoside family of carbohydrate mimetics. 2-Bromooxepines are obtained through silver(I)-promoted thermal ring expansion of a D-glucal-derived gem-dihalocyclopropanated sugar. In contrast, cyclopropane ring cleavage under basic conditions leads to 2-C-branched pyranosides, not the 2-bromooxepine structures assigned in an earlier report.