催化酶选择性Friedel-Crafts 艾利化 催化酶选择性艾利化
Priyotosh Das1, Debangshu Ghosh1, Santanu Mukherjee1
1Department of Organic Chemistry, Indian Institute of Science, Bangalore 560 012, India.
Angewandte Chemie (International ed. in English)
|August 7, 2024
概括
这项研究引入了第一个enantioselectiveFriedel-Crafts基化,使用raceme的基醇制造了中央性. 该方法有效地合成了具有高反净度和区域控制的奇拉性艾伦基甲.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 合成方法论 合成方法论
背景情况:
- 弗里德尔-克拉夫茨反应是有机合成的基础.
- 开发用于创建奇拉中心的enantioselective方法至关重要.
- 化反应提供了独特的合成途径.
研究的目的:
- 开发了第一个enantioselectiveFriedel-Crafts基化反应.
- 使用随时可用的racemicallenylic酒精来创建中心的奇拉性.
- 建立一种合成高丰富的基甲的方法.
主要方法:
- 使用 (I) 和胺/烯联体的合作催化.
- 采用易斯酸催化剂与种族性艾伦醇作为电友.
- 利用富含电子的和异作为核友.
主要成果:
- 实现了第一个enantioselectiveFriedel-Crafts全基结.
- 合成的1,1-非替代的艾伦基甲,具有高达99.5%的反体比率 (e.r.r. ) 的情况.
- 在 (异质) 场和基碎片上都表现出完全的区域控制.
- 展示了成功的合成加工方法,用于整形和元选择性基化.
- 在分子内变体中观察到有前途的反选择性.
结论:
- 开发了一种强大的协议,用于对抗选择性弗里德尔-克拉夫特斯基化.
- 反应通过动态动力学非对称转换 (DyKAT) 进行.
- 这种方法允许对四碳链进行对抗选择性引入,并创建基立体中心.
相关概念视频
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Friedel–Crafts reactions were developed in 1877 by the French chemist Charles Friedel and the American chemist James Crafts. Friedel–Crafts alkylation refers to the replacement of an aromatic proton with an alkyl group via electrophilic aromatic substitution. A Lewis acid catalyst such as aluminum chloride reacts with an alkyl halide to form a carbocation. The resulting carbocation then reacts with the aromatic ring and undergoes a series of electron rearrangements before giving the...
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01:26Limitations of Friedel–Crafts Reactions
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01:11Electrophilic Aromatic Substitution: Friedel–Crafts Acylation of Benzene
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