Enantioselective Synthesis of Tetrahydropyrano[3,4-b]indoles Catalyzed by Chiral N-Triflyl Phosphoramide via Intramolecular Friedel-Crafts Alkylation Reaction - Zhang, Jun-Wei; Cai, Quan; Shi, Xiao-Xin; Zhang, Wei; You, Shu-Li (Synlett, 2011)