Copper-catalyzed three-component annulation toward pyrroles via the cleavage of two C-C bonds in 1,3-dicarbonyls.

The first copper-catalyzed three-component annulation of α,β-unsaturated ketoximes, 1,3-dicarbonyls and paraformaldehyde has been documented. This novel strategy achieved the two C-C bond cleavage of 1,3-dicarbonyl compounds directly as a single-carbon synthon and provided a new and highly efficient method for the synthesis of 2,3-disubstituted pyrroles in moderate to good yields with broad functional group compatibility.