butan-2-yl-(2,3-dimethylbutan-2-yl)-methoxyborane | 112398-78-4

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 硼酸衍生物
• 英文名称: butan-2-yl-(2,3-dimethylbutan-2-yl)-methoxyborane
• CAS: 112398-78-4
• 化学式: C₁₁H₂₅BO
• 分子量: 184.13
• InChiKey: HWSPZLMIRAWKKI-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.86
• 重原子数：
  13.0
• 可旋转键数：
  5.0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  9.23
• 氢给体数：
  0.0
• 氢受体数：
  1.0

反应信息

• 作为反应物：
  描述：

  butan-2-yl-(2,3-dimethylbutan-2-yl)-methoxyborane 、 三甲基乙炔基硅 生成 3-Methyl-1-(trimethylsilyl)-1-pentyne
  参考文献：
  名称：

  Chiral synthesis via organoboranes. 29. A general synthesis of .alpha.-chiral monosubstituted acetylenes and their trimethylsilyl derivatives from enantiomerically pure boronic esters

  摘要：

  The procedure for the synthesis of RC = CH by the iodination of [R3BC = CH]-Li+ is impractical for the synthesis of the corresponding chiral derivatives, R*C = CH, due to the unavailability of the required R*3B compounds. RThxBOMe and R*ThxBOCH3, now readily available by established procedures, serve handily for the syntheses of RC = CR' and R*C = CR respectively from LiC = CR, but fail for the syntheses of either RC = CH or R*C = CH, in reasonable yield, from LiC = CH. Fortunately, this difficulty can be circumvented by utilizing LiC = CSiMe3. Indeed, treatment of enantiomerically pure monoalkylthexylborinates, R*ThxBOCH3, readily prepared from enantionerically pure boronic esters, with LiC = CSiMe3 forms an ate complex which readily undergoes the desired iodine-induced rearrangement, forming alpha-chiral (trimethylsilyl)acetylenes, R*C = CSiMe3. The (trimethylsilyl)acetylenes are easily desilylated to afford the corresponding alpha-chiral terminal acetylenes, R*C = CH, in yields of approximately 70% and essentially 100% enantiomeric excess (greater-than-or-equal-to 99%). These intermediates, R*C = CSiMe3 and R*C = CH, can be readily converted by simple procedures into a wide variety of pure enantiomers: R*CH = CH2, R*CH2CHO, R*CO2H, R*CH2CO2H, R*COCO2R, etc. Since both (+)- and (-)-alkylboronic esters are now readily available in essentially 100% enantiomeric purity, it is now possible to synthesize (+)- and (-)-alpha-chiral monosubstituted acetylenes and their trimethylsilyl derivatives in very high enantiomeric purities. This provides the first general, efficient synthesis of these valuable synthons in such high enantiomeric purities.

  DOI：

  10.1021/jo00004a030