Organocatalyst-Controlled Divergent Asymmetric Aza-Friedel-Crafts Reactions of Indol-3-ones with 1-and 2-Naphthols

Indol-3-ones are readily available reaction substrates, but their utility in asymmetric reactions is underdeveloped. Herein, we describe the organocatalytic asymmetric aza-Friedel-Crafts-type reaction of indol-3-ones with 1- and 2-naphthols. By using spirocyclic chiral phosphoric acids and quinine-incorporated squaramides as the organocatalysts, two classes of structurally distinct chiral compounds, namely 2-(hydroxylnaphthyl)-indolin-3-ones and tetrahydrofuroindoles, are formed respectively. These quaternary centre-containing indoline derivatives may find use in the synthesis of biologically active molecules.

Automated summary

In this study, the organocatalytic asymmetric aza-Friedel-Crafts-type reaction of indol-3-ones with 1- and 2-naphthols was performed using spirocyclic chiral phosphoric acids and quinine-incorporated squaramides as the organocatalysts. Two classes of structurally distinct chiral compounds, namely 2-(hydroxylnaphthyl)-indolin-3-ones and tetrahydrofuroindoles, were formed. These quaternary centre-containing indoline derivatives may have applications in the synthesis of biologically active molecules.