Sequential One-Pot Synthesis of β-Amino-γ-keto-malonates from Nitro-Substituted Donor-Acceptor Cyclopropanes

A sequential one-pot procedure has been developed for the access of β-Amino-γ-keto-malonates from nitro-substituted donor-acceptor cyclopropanes and four different N-compounds. The reaction proceeds through in situ generation of aroylmethylidenemalonates from the nitro cyclopropanes via Kornblum type ring-opening oxidation using DMSO and subsequent aza-Michael addition with the N-compounds. To prove the synthetic utility of the resulting products, one of them was transformed into a pyridazinone derivative.