强的C-H键的直接结合
Ian B Perry1, Thomas F Brewer1, Patrick J Sarver1
1Merck Center for Catalysis at Princeton University, Princeton, NJ, USA.
Nature
|August 3, 2018
概括
这项研究引入了一种新的双催化方法,用于直接的C ((sp3) 结合. 它有效地将丰富的形C-H键与基合,在温和条件下产生有价值的C-sp3-C-sp2键.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 过渡金属催化在功能化sp3混合碳原子方面存在局限性.
- 直接的C-H键功能化是理想的,但对于强的中性C ((sp3) -H键具有挑战性.
- 现有的方法通常需要预先功能化的基板或恶劣的条件.
研究的目的:
- 开发一个温和的和一般的协议直接C ((sp3) 结合的C-H纽带.
- 通过使用易于获得的原材料来形成C(sp3) -C(sp2) 键.
- 为复杂的药物分子提供新合成途径.
主要方法:
- 一个双催化系统,结合光驱动的原子转移 (HAT) 和催化.
- 聚氧甲光催化剂使HAT从强的中性C-H键产生以碳为中心的基因.
- 催化剂介导这些基因与基的交叉合.
主要成果:
- 不同的异形框架的成功直接C ((sp3) 结合.
- 在温和条件下形成C ((sp3) -C ((sp2) 交联产物.
- 已证明适用于天然产品和化学原料.
结论:
- 开发的协议提供了前所未有的单步访问复杂的分子.
- 这种方法克服了sp3混合碳的传统交叉合反应的局限性.
- 这项技术可以在以前没有反应的场所实现功能化,扩大合成的可能性.
相关概念视频
Titration Calculations: Strong Acid - Strong Base
34.0K
Calculating pH for Titration Solutions: Strong Acid/Strong Base
A titration is carried out for 25.00 mL of 0.100 M HCl (strong acid) with 0.100 M of a strong base NaOH. The pH at different volumes of added base solution can be calculated as follows:
(a) Titrant volume = 0 mL. The solution pH is due to the acid ionization of HCl. Because this is a strong acid, the ionization is complete and the hydronium ion molarity is 0.100 M. The pH of the solution is then:
A titration is carried out for 25.00 mL of 0.100 M HCl (strong acid) with 0.100 M of a strong base NaOH. The pH at different volumes of added base solution can be calculated as follows:
(a) Titrant volume = 0 mL. The solution pH is due to the acid ionization of HCl. Because this is a strong acid, the ionization is complete and the hydronium ion molarity is 0.100 M. The pH of the solution is then:
34.0K
Covalent Bonds
163.1K
Overview
163.1K
Hydrogen Bonds
133.9K
Hydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
133.9K
Crossed Aldol Reaction Using Strong Bases: Directed Aldol Reaction
2.8K
The reaction between two different carbonyl compounds comprising α hydrogen in the presence of a strong base like lithium diisopropylamide (LDA) to form a crossed aldol product is known as a directed aldol reaction. The directed aldol reaction is depicted in Figure 1.
2.8K
Bond Energies and Bond Lengths
31.5K
Stable molecules exist because covalent bonds hold the atoms together. The strength of a covalent bond is measured by the energy required to break it, that is, the energy necessary to separate the bonded atoms. Separating any pair of bonded atoms requires energy — the stronger a bond, the greater the energy required to break it.
31.5K
Peptide Bonds
83.2K
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
83.2K


