[2+2] Cycloaddition of Electron-Poor Acetylenes to Enaminones

Microwave-assisted [2+2] cycloadditions of (E)-3-dimethylamino-1-substituted prop-2-en-1-ones, prepared from carbocyclic, aromatic and heteroaromatic methyl ketones, ethyl acetate, diethyl malonate, ethyl methoxyacetate, methyl phenoxyacetate and dietyl acetylenedicarboxylate give substituted dimethyl 2-[(dimethylamino)methylene]succinates.