Diastereoselective Synthesis of N-Aryl Tetrahydroquinolines and N-Aryl Indolines by the Tandem Reaction of Arynes

A tandem reaction of arynes with alpha- or beta-amino ketones has been revealed. Arynes react with beta-amino ketones through a cascade insertion cyclization process to afford N-aryl tetrahydroquinolines in good yield with excellent anti-selectivity. Meanwhile, the coupling of arynes with alpha-amino ketones produces multisubstituted indolines in high yield with syn-selectivity. A quaternary carbon center can be constructed in this process, and the reaction can be easily scaled up.