School of Chemistry & Chemical Engineering, Jiangsu Normal University, Xuzhou, 221116, China.
J Org Chem. 2012 Aug 17;77(16):6970-9. doi: 10.1021/jo301174g. Epub 2012 Aug 2.
An organocatalytic asymmetric three-component Povarov reaction involving 2-hydroxystyrenes has been established to provide an efficient method to access structurally diverse cis-disubstituted tetrahydroquinolines in high stereoselectivities of up to >99:1 dr and 97% ee. This protocol also provides an easy access to tetrahydroquinolines with chiral quaternary stereocenters upon using α-alkyl 2-hydroxystyrenes as substrates. The theoretical studies revealed that the Povarov reaction proceeded through a sequential vinylogous Mannich reaction and an intramolecular Friedel-Crafts reaction, wherein the phosphoric acid acted as bifunctional catalyst to activate 2-hydroxystyrene and aldimine simultaneously.
建立了一种涉及 2-羟基苯乙烯的有机催化不对称三组分 Povarov 反应，为在高立体选择性（高达＞99:1 dr 和 97%ee）下获得结构多样的顺式二取代四氢喹啉提供了一种有效方法。该方案还提供了一种使用α-烷基 2-羟基苯乙烯作为底物轻松获得具有手性季碳中心的四氢喹啉的方法。理论研究表明，Povarov 反应通过顺序的乙烯基曼尼希反应和分子内傅克反应进行，其中磷酸作为双功能催化剂同时激活 2-羟基苯乙烯和亚胺。
