title: Triply Hydrogen-Bond-Directed Enantioselective Assembly of Pyrrolobenzo-1,4-diazine Skeletons with Quaternary Stereocenters.
abstract: Highly efficient synthesis of optically enriched pyrrolobenzo-1,4-diazines bearing quaternary stereocenters has been realized through the chiral Brønsted acid-catalyzed Pictet-Spengler reaction of 2-(1H-pyrrol-1-yl)anilines and α-ketoamides in good to excellent yields and enantioselectivities. Computational studies suggest an unprecedented phenomenon whereby the chiral phosphoric acid catalyst employs attractive arene C-H⋅⋅⋅N hydrogen bonding to activate the substrate and induce chirality through a triple hydrogen-bonding interaction.
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027 (P.R. China), Fax: (+86) 571-87952759.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Shen
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027 (P.R. China), Fax: (+86) 571-87952759.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027 (P.R. China), Fax: (+86) 571-87952759.
authors.forename: Tiandi
authors.initials: T
authors.lastname: Wu
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027 (P.R. China), Fax: (+86) 571-87952759.
authors.forename: Zhenjun
authors.initials: Z
authors.lastname: Mao
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027 (P.R. China), Fax: (+86) 571-87952759. lxfok@zju.edu.cn.
authors.forename: Xufeng
authors.initials: X
authors.lastname: Lin
keywords: Brønsted acids; Pictet-Spengler reaction; chirality; organocatalysis; phosphoric acids