Copper(I)-Catalyzed [ 3+ 2] Cycloaddition of 3-Azidoquinoline-2,4(1H,3H)-diones with Terminal Alkynes

3-Azidoquinoline-2,4(1H,3H)-diones 1, which are readily available from 4-hydroxyquinolin-2(1H)-ones 4 via 3-chloroquinoline-2,4(1H,3H)-diones 5, afford, in copper(I)-catalyzed [3 + 2] cycloaddition reaction with terminal acetylenes, 1,4-disubstituted 1,2,3-triazoles 3 in moderate to excellent yields. The structures of compounds 3 were confirmed by 1H and 13C-NMR spectroscopy, combustion analyses and mass spectrometry