基催化剂用于用硫胺和弱基anilin用硫胺和弱基anilin进行olefin的胺化
Dmitry Karshtedt1, Alexis T Bell, T Don Tilley
1Department of Chemistry and Chemical Engineering, University of California, Berkeley, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|September 8, 2005
概括
电友 (((II) 复合物有效地利用硫胺和氨酸催化烯酸胺化. 这项研究确定了基质的pKa切断点,并阐明了催化机制,揭示了Pt激活的烯通路.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 合成化学 合成化学
背景情况:
- 胺化反应对于合成含化合物至关重要.
- 在有机合成中,开发高效的胺化催化剂仍然是一个重大挑战.
研究的目的:
- 为了研究电友复合物在催化氨酸胺化中的有效性.
- 为了确定这种催化过程的基质范围和机械细节.
主要方法:
- 使用 (Pt) 复合物,包括 (COD) Pt (OTf) 2,作为催化剂.
- 作为源使用替代的阿尼林和阿里硫胺.
- 使用NMR光谱学 (19F,195Pt) 和质谱学特征反应中间体.
- 进行了动力学研究以确定速率定律.
主要成果:
- 通过在90°C时与烯硫胺进行烯酸胺化,获得了高产率 (>95%) .
- 确定了含基板的经验pKa截止值 (<1).
- 在烯胺化中证明了马尔科夫尼科夫的选择性,表明Pt-olefin激活.
- 鉴定和描述了一个关键的催化中间体,[(COD) Pt(norbornene) [2][OTf]2.2.
- 确定速率定律为速率=k(obs) [Pt][硫胺].
结论:
- 电性Pt(II) 复合物是用硫胺和弱基anilin来胺化烯酸的有效催化剂.
- 催化机制涉及Pt激活的烯物种和硫胺攻击作为速度决定的步骤.
- 这项工作为催化胺化反应的范围和机制提供了宝贵的见解.
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