β-Carbon activation of saturated carboxylic esters through N-heterocyclic carbene organocatalysis
β-Carbon activation of saturated carboxylic esters through N-heterocyclic carbene organocatalysis
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DOI：
10.1038/nchem.1710
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发表时间：
2013-10-01
期刊：
影响因子：
21.8
通讯作者：
Chi, Yonggui Robin
中科院分区：
文献类型：
--
作者：
Fu, Zhenqian;Xu, Jianfeng;Chi, Yonggui Robin
羧酸酯和相关羰基化合物的α -碳活化生成烯酸酯等价物作为亲核试剂是有机合成中最有效的策略之一。我们认为，如果饱和酯的典型惰性碳可以用作亲核试剂，化学合成的范围将大大扩大。然而，尽管具有相当重要的基础和实用价值，直接利用饱和羰基化合物的β -碳作为亲核试剂仍然是难以实现的。在这里，我们报告了用n -杂环碳有机催化剂催化活化简单饱和酯碳作为亲核试剂（β碳活化）。催化生成的亲核-碳与亲电试剂如烯酮和亚胺发生对映选择反应。考虑到酯-碳的丰富化学性质，我们期望饱和酯-碳的这种催化活化模式为新的和有用的反应和合成策略开辟一个有价值的新领域。
The activation of the alpha-carbons of carboxylic esters and related carbonyl compounds to generate enolate equivalents as nucleophiles is one of the most powerful strategies in organic synthesis. We reasoned that the horizons of chemical synthesis could be greatly expanded if the typically inert beta-carbons of saturated esters could be used as nucleophiles. However, despite the rather significant fundamental and practical values, direct use of the beta-carbons of saturated carbonyl compounds as nucleophiles remains elusive. Here we report the catalytic activation of simple saturated ester b-carbons as nucleophiles (beta-carbon activation) using N-heterocyclic carbene organocatalysts. The catalytically generated nucleophilic beta-carbons undergo enantioselective reactions with electrophiles such as enones and imines. Given the proven rich chemistry of ester alpha-carbons, we expect this catalytic activation mode for saturated ester beta-carbons to open a valuable new arena for new and useful reactions and synthetic strategies.