由氧基烯复合物促进的Z-选择性烯基基解剖反应
Dmitry V Peryshkov1, Richard R Schrock, Michael K Takase
1Department of Chemistry 6-331, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|November 24, 2011
概括
一种新型的烯催化剂促进Z选择性烯酸合,实现高产量和立体选择性. 用化合物激活可增强热力学产物形成的催化活性.
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.
- 有机合成 有机合成
背景情况:
- 氧复合物在各种催化转化中至关重要.
- 在有机合成中,开发用于烯酸合的选择性催化剂仍然是一个重大挑战.
研究的目的:
- 为了合成和表征新的氧复合物.
- 评估这些复合体在Z选择性烯酸合反应中的催化活性.
- 为了研究易斯酸激活对催化性能的影响.
主要方法:
- 通过连接剂添加反应合成氧复合物.
- 使用光谱技术进行表征 (摘要中没有提供细节).
- 在Z选择性烯酸合与终端烯酸的催化试验.
- 路易斯酸激活使用tris(pentafluorophenyl) ..
主要成果:
- 合成了一种新的氧复合物,W ((O) ((CH-t-Bu) ((OHMT) ((Me ((2) Pyr) ((PMe ((2) Ph) (5),是可以合成的.
- 复合物5证明了作为终端烯酸的Z选择性合的催化剂的高效性,在0.2%的负载下产生>75%的产品,具有>99%的Z配置.
- 用B的复合体5的激活产生了一个高度活跃的催化剂 (5·B的C的F的5) 的3)),产生了热力学产物 (~20%的Z).
结论:
- 合成的氧复合体5是Z选择性烯酸合的高效催化剂.
- 易斯酸激活B (C) (6) (F) (5)) (3) 改变了催化剂的活性和选择性.
- 这项研究为立体选择性烯酸转换提供了一个新的催化系统.
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