Chiral Bronsted acid-catalyzed direct Mannich reactions via electrophilic activation
Chiral Bronsted acid-catalyzed direct Mannich reactions via electrophilic activation
复制标题
DOI：
10.1021/ja0491533
复制
发表时间：
2004-05-05
影响因子：
15
通讯作者：
Terada, M
中科院分区：
文献类型：
--
作者：
Uraguchi, D;Terada, M
结果表明，结构式1的磷酸衍生物对乙酰丙酮与N-叔丁氧羰基保护的芳基亚胺的直接加成反应具有很高的催化活性。催化剂中的3，3 ′-二芳基取代基对反应的对映选择性有很大的影响，是一种优良的催化剂。本文提出的Brønsted酸催化的直接Mannich反应提供了一种在极其温和的条件下构建β-氨基酮的有吸引力的方法。通过Boc-（S）-苯甘氨酸甲酯的合成，确定了该反应的立体化学过程。由此证明的转化适用于合成各种苯甘氨酸衍生物的有用方法。
It was found that the phosphoric acid derivatives of general structure1serve as highly effective catalysts for the direct addition of acetyl acetone toN-Boc-protected arylimines. The beneficial effects of the 3,3‘-bisaryl substituents of the catalysts on the enantioselectivity are greatly appreciated, and thus1dfunctions as an excellent catalyst. The Brønsted acid-catalyzed direct Mannich reactions presented herein provide an attractive way to construct β-aminoketones under extremely mild conditions. The stereochemical course of this reaction was established through the synthesis of Boc-(S)-phenylglycine methylester. The transformation thus demonstrated is applicable to a useful method for the synthesis of various phenylglycine derivatives.