由离子催化的选择性伊降解
Travis Lundrigan1, Erin N Welsh1, Toren Hynes1
1Department of Chemistry , Dalhousie University , Halifax , Nova Scotia , Canada B3H 4R2.
Journal of the American Chemical Society
|August 24, 2019
概括
酸在不对称催化中用于有效的循环 imines 的水解和水化. 这种方法甚至可以在具有挑战性的基质中产生高反选择性的有价值的皮罗利丁和皮佩里丁.
科学领域:
- 有机金属化学
- 不对称的催化
- 合成有机化学
背景情况:
- 酸是有反应性的物种.
- 不对称的催化对于合成性分子至关重要.
- 开发具有挑战性的新催化剂仍然是一个活跃的研究领域.
研究的目的:
- 报告在不对称催化中第一次应用酸.
- 开发一个用于循环 imines 的 enantioselective 化和化的催化系统.
- 合成功能化皮罗利丁和皮佩里丁.
主要方法:
- 在多克尺度上制备三催化剂.
- 催化不对称的水解和循环 imines 的水化.
- 合成产品的特征
主要成果:
- 酸三酸盐催化了高达97:3的反分子比率.
- 低于0.2%的催化剂负荷是有效的.
- 合成了22种烯/异烯和烯.
- 这种方法成功地减少了具有具有挑战性的功能群的 imines,
结论:
- 酸是不对称合成的新型有效催化剂.
- 这种方法提供了一种通用的途径,用于奇拉 pyrrolidines 和 piperidines.
- 开发的系统克服了某些基质的传统过渡金属催化剂的局限性.
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