A copper-catalyzed
three-component reaction of methyl ketones,
organic azides, and various one-carbon (C1) donors was developed that
provides 4-acyl-1,2,3-triazoles in moderate to good yields. While
DMF, DMA, TMEDA, or DMSO can serve as the C1 donor, best yields were
obtained using DMF. The transformation is proposed to proceed via
an oxidative C–H/C–H cross-dehydrogenative coupling
followed by an oxidative 1,3-dipolar cycloaddition
