An efficient silver catalyzed annulation reaction of aryne with nitriles to generate quinazolines is described. Arynes generated from triynes or tetraynes through a hexadehydro Diels-Alder reaction readily participated in an [A + 2B] mode of annulation with nitriles in the presence of AgSbF catalyst. The mechanism was explored by DFT calculations, which supports the silver-catalyzed formation of nitrilium ion as a key intermediate. This annulation generates an array of polysubstituted novel quinazoline derivatives with excellent regioselectivity.
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