Silver Triflate Catalyzed Reaction of 2-Alkynylbenzaldoxime with Aryne

A novel and unexpected reaction of 2-alkynylbenzaldoxime with aryne in the presence of silver triflate (10 mol %) under mild conditions is discovered. This reaction proceeds through 6-endo-cyclization, [3 + 2] cycloaddition, and rearrangement, leading to 2-oxa-6-aza-bicyclo[3.2.2]nona-6,8-diene derivatives in moderate to good yields.