Triarylaminium Salt-Initiated Aerobic Double Friedel-Crafts Reaction of Glycine Derivatives with Indoles

A novel and efficient stable radical cation triarylaminium salt-catalyzed aerobic double Friedel-Crafts alkylation reaction of glycine derivatives with indoles has been developed. The reaction was performed in the absence of any other additives under mild conditions and only requires an air atmosphere (or oxygen, 1 atm) as co-oxidant.