Highly Enantioselective Michael Addition of 2-Oxindole- 3-carboxylate Esters to Nitroolefins Promoted by Cinchona Alkaloid-Thiourea-Brønsted Acid Cocatalysts
作者:Xianjie Chen、Wei Zhu、Wangke Qian、Enguang Feng、Yu Zhou、Jinfang Wang、Hualiang Jiang、Zhu-Jun Yao、Hong Liu
DOI:10.1002/adsc.201200206
日期:2012.8.13
A highly efficient organocatalyzed Michael addition of 2-oxindole-3-carboxylate esters to nitroolefins using a Cinchona alkaloid-thiourea and an achiral Brønsted acid as cooperative organocatalysts is reproted that affords significantly improved enantioselectivity and diastereoselectivity. It also provides an efficient approach to the synthesis of spirooxindole derivatives with high enantioselectivity
使用金鸡纳生物碱-硫脲和非手性布朗斯台德酸作为协同有机催化剂,可以高效地将2-氧吲哚-3-羧酸酯的迈克尔加成到硝基烯烃上,从而大大提高了对映选择性和非对映选择性。它还为合成具有高对映选择性的螺并恶吲哚衍生物提供了一种有效的方法。