Chemoselectivity issues of the asymmetric interaction between cyclohexanone, β‐nitrostyrene, and benzoic acid under 5‐aryl prolinate's organocatalysis
作者:Polina M. Ivantcova、Konstantin V. Kudryavtsev
DOI:10.1002/chir.23212
日期:2020.6
4‐l‐menthyloxycarbonyl 5‐aryl prolinates were studied as organocatalysts of a novel three‐component reaction of cyclohexanone, benzoic acid, and β‐nitrostyrene. The presence of ortho‐halogen atom in 5‐aryl fragment of the catalyst is favored for driving the formation of chiral 7a‐hydroxyoctahydro‐2H‐indol‐2‐one scaffold. 5‐(o‐Chlorophenyl) prolinate selectively afforded 3‐phenyl‐7a‐hydroxyoctahydro‐2H‐indol‐2‐one
4-升-menthyloxycarbonyl 5-芳prolinates进行了研究如环己酮,苯甲酸,和β硝基苯乙烯的一种新颖的三组分反应的有机催化剂。催化剂5-芳基片段中存在邻卤素原子有助于推动手性7a-羟基八氢-2 H-吲哚-2-酮骨架的形成。脯氨酸5-(邻-氯苯基)选择性提供ee 63%的3-苯基-7a-羟基八氢-2 H-吲哚-2-酮,而脯氨酸5-苯基导致β-硝基苯乙烯与环己酮结合(迈克尔加合物) 。可能的氯作用是过渡态的5-芳基脯氨酸脯氨酸烯胺中间体与β-硝基苯乙烯之间特定相互作用的原因。