Enantioselective Friedel–Crafts reaction of indoles with arylidene malonates catalyzed by iPr-bisoxazoline–Cu(OTf)2

Abstract

The cheap and simple ⁱPr-bisoxazoline–Cu(OTf)₂ proves to be an efficient catalyst in the asymmetric Friedel–Crafts reaction of indole with arylidene malonates. In ⁱBuOH, the S-enantiomer was obtained in up to 97% ee, while the opposite enantiomer was obtained in up to 78% ee in CH₂Cl₂ or TTCE.