Direct Mannich-Type Reactions Promoted by Frustrated Lewis Acid/Brønsted Base Catalysts
作者:Jessica Z. Chan、Wenzhi Yao、Brian T. Hastings、Charles K. Lok、Masayuki Wasa
DOI:10.1002/anie.201608583
日期:2016.10.24
Direct Mannich‐type reactions that afford both α‐ and β‐amino esters by the reaction of a broad range of carbonyl compounds and aldimines are disclosed. The transformation is promoted by a sterically frustrated Lewis acid/Brønsted base pair, which is proposed to operate cooperatively: Within the catalyst complex, an enolate is generated that then reacts with a hydrogen‐bond‐activated imine. Noncovalent
公开了直接曼尼希型反应,该反应通过多种羰基化合物和醛亚胺的反应提供α-和β-氨基酯。建议通过空间受阻的路易斯酸/布朗斯台德碱对促进转化,该碱对可协同操作:在催化剂配合物中生成烯醇盐,然后该烯醇盐与氢键活化的亚胺反应。反应物与催化剂之间的非共价相互作用为将来的催化剂设计提供了选择性和新的机会。