(2E,4R)-4-(4’,4',5',5'-tetramethyl-1',3',2’-dioxaboranyl)-3-methylpent-2-ene | 1428538-09-3

• 分子结构分类: 有机化合物 - 有机杂环化合物
• 英文名称: (2E,4R)-4-(4’,4',5',5'-tetramethyl-1',3',2’-dioxaboranyl)-3-methylpent-2-ene
• 英文别名: (R,E)-2-(2,4-dimethylhex-4-en-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane
• CAS: 1428538-09-3
• 化学式: C₁₄H₂₇BO₂
• 分子量: 238.178
• InChiKey: BTSZOWKCHJATPX-LMMOQWNQSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.07
• 重原子数：
  17.0
• 可旋转键数：
  3.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.86
• 拓扑面积：
  18.46
• 氢给体数：
  0.0
• 氢受体数：
  2.0

反应信息

• 作为反应物：
  描述：

  (2E,4R)-4-(4’,4',5',5'-tetramethyl-1',3',2’-dioxaboranyl)-3-methylpent-2-ene 、 苯甲醛 在 正丁基锂 、 三氟乙酸酐 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 16.75h， 以78%的产率得到(1S,2S,3E)-1-hydroxy-2,3,5-trimethyl-1-phenylhex-3-ene
  参考文献：
  名称：

  Highly Diastereo- and Enantioselective Allylboration of Aldehydes using α-Substituted Allyl/Crotyl Pinacol Boronic Esters via in Situ Generated Borinic Esters

  摘要：

  Readily available, alpha-substituted allyl/crotyl pinacol boronic esters often give low E/Z selectivity (with Z favored) in reactions with aldehydes. We found that addition of nBuLi to the pinacol boronic ester followed by trapping of the alkoxide with TFAA leads to an intermediate allyl borinic ester which undergoes allylboration with very high E selectivity. The substrate scope includes primary to tertiary alkyl alpha-substituents, crotyl substrates, and the previously unreported beta-methallyl pinacol boronic esters. The latter give very high Z selectivity under standard conditions which is completely reversed to high E selectivity under the new conditions. Monitoring the reaction by B-11 NMR confirmed that the reaction proceeds through a borinic ester intermediate.

  DOI：

  10.1021/ja401564z
• 作为产物：
  描述：

  频那醇硼烷 在 Schwartz's reagent 、 (2-methylpropyl)lithium 、 鹰爪豆碱 作用下， 以 乙醚 、 正己烷 、 二氯甲烷 、 环己烷 为溶剂， 反应 52.0h， 生成 (2E,4R)-4-(4’,4',5',5'-tetramethyl-1',3',2’-dioxaboranyl)-3-methylpent-2-ene
  参考文献：
  名称：

  Highly Diastereo- and Enantioselective Allylboration of Aldehydes using α-Substituted Allyl/Crotyl Pinacol Boronic Esters via in Situ Generated Borinic Esters

  摘要：

  Readily available, alpha-substituted allyl/crotyl pinacol boronic esters often give low E/Z selectivity (with Z favored) in reactions with aldehydes. We found that addition of nBuLi to the pinacol boronic ester followed by trapping of the alkoxide with TFAA leads to an intermediate allyl borinic ester which undergoes allylboration with very high E selectivity. The substrate scope includes primary to tertiary alkyl alpha-substituents, crotyl substrates, and the previously unreported beta-methallyl pinacol boronic esters. The latter give very high Z selectivity under standard conditions which is completely reversed to high E selectivity under the new conditions. Monitoring the reaction by B-11 NMR confirmed that the reaction proceeds through a borinic ester intermediate.

  DOI：

  10.1021/ja401564z

文献信息

• An Efficient Approach to Chiral Allyloxyamines by Stereospecific Allylation of Nitrosoarenes with Chiral Allylboronates
  作者：Yuanming Li、Shyamal Chakrabarty、Armido Studer

  DOI：10.1002/anie.201410188

  日期：2015.3.16

  A novel and efficient approach to allyloxyamines by the allylation of nitrosoarenes with α‐chiral allylboronates is described. CO bond formation occurs with high stereospecificity and the product allyloxyamines are easily transformed into valuable chiral building blocks such as isoxazolidines and allylic alcohols. The reaction features complete regioselectivity (O‐selectivity), high E/Z selectivity

  通过亚硝基芳烃与α-手性烯丙基硼酸酯的烯丙基化，提出了一种新颖有效的烯丙氧基胺方法。Ç  O键的形成具有高立体定向性和发生产品allyloxyamines很容易转化成有价值的手性结构单元如异恶唑烷和烯丙醇。该反应具有完全的区域选择性（O-选择性），高的E / Z选择性和出色的手性传递特性。