Modification of Pseudo-C3-Symmetric Trisoxazoline and Its Application to the Friedel-Crafts Alkylation of Indoles and Pyrrole with Alkylidene Malonates

New pseudo-C3-symmetric hetero-trisoxazoline can be easily prepared on a gram scale in good yield. Its combination with copper(II) triflate exhibits high enantiomeric induction in the asymmetric Friedel-Crafts alkylation between indoles and alkylidene malonates, with up to 97% ee and good to excellent yields. The catalyst loading can be lowered to 0.5 mol% without loss of the enantiomeric excess.