Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan.
Org Lett. 2018 Feb 2;20(3):526-529. doi: 10.1021/acs.orglett.7b03609. Epub 2018 Jan 14.
A direct catalytic Mannich-type reaction of α-oxygen-functionalized amides was achieved. The use of 7-azaindoline amide was crucial to facilitate direct enolization and subsequent stereoselective addition to imines in a cooperative catalytic system comprising a soft Lewis acid and Brønsted base. The operationally simple room-temperature protocol furnished a syn-Mannich adduct with high stereoselectivity. Divergent functional group transformation of the amide moiety of the product allowed for expeditious access to enantioenriched syn-configured α-hydroxy-β-amino carboxylic acid derivatives, highlighting the synthetic utility of the present catalysis.
实现了α-氧官能化酰胺的直接催化曼尼希型反应。在包含软路易斯酸和布朗斯特碱的协同催化体系中,7-氮茚酰胺的使用对于促进直接烯醇化和随后对亚胺的立体选择性加成至关重要。该操作简单的室温方案提供了具有高立体选择性的顺式-Mannich 加合物。产物中酰胺部分的不同官能团转化允许快速获得对映富集的顺式构型α-羟基-β-氨基羧酸衍生物,突出了本催化的合成实用性。