Diazoacetoacetate enones are a new class of Michael acceptors that enable the efficient construction of natural product-like scaffolds. Through their Michael addition reactions, including those with silyl enol ethers, indoles, pyrroles, and amines, δ-functionalized diazoacetoacetates are formed in high yield and with overall operational efficiency. Subsequent catalytic dinitrogen extrusion reactions provide access to a diverse series of natural product-like carbo- and heterocyclic ring systems in only three steps from commercial materials.