一种轻微的C-O键形成,由氧复合物催化
Benjamin D Sherry1, Alexander T Radosevich, F Dean Toste
1Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley 94720, USA.
Journal of the American Chemical Society
|June 6, 2003
概括
一种新的催化方法使得能够轻度和区域选择性合成甲基乙烯. 这种高效的过程使用氧复合物形成碳氧键,耐受多种功能组.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 甲基乙烯是有价值的合成中间体.
- 现有的合成方法通常需要恶劣的条件或先前的激活步骤.
研究的目的:
- 开发一种温和和区域选择性方法来合成基乙烯.
- 为了利用耐空气和耐湿性催化剂形成C-O键.
主要方法:
- 甲基酒精与各种酒精的合.
- 使用氧复合物 ((dppm) ReOCl3) 的催化.
- 不需要先前激活propargyl酒精或核爱体的deprotonation.
主要成果:
- 在温和条件下成功地进行了propargyl的区域选择性合成.
- 氧催化剂显示出对空气和水分的耐受性.
- 宽泛的功能组耐受性,包括烯化物,烯,,乙,初级基化物和合.
- 酒精在其他电友上具有优越的排位.
结论:
- 已经建立了一种新的,温和的,区域选择性的催化方法来合成甲基以太.
- 氧复合物为sp3碳氧键的形成提供了高效和强大的催化剂.
- 该方法对各种功能组的耐受性和化学选择性使其在有机合成中广泛适用.
相关概念视频
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Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Properties of Organometallic Compounds
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C–C Bond Cleavage: Retro-Aldol Reaction
The reverse of the aldol addition reaction is called the retro-aldol reaction. Here, the carbon–carbon bond in the aldol product is cleaved under acidic or basic conditions to form two molecules of carbonyl compounds. The mechanism of the reaction consists of three steps.
In the first step, as depicted in Figure 1, the base deprotonates the β-hydroxy ketone at the hydroxyl group to form an alkoxide ion.
In the first step, as depicted in Figure 1, the base deprotonates the β-hydroxy ketone at the hydroxyl group to form an alkoxide ion.


