3-Methylene-4-amido-1,2-diazetidine as a Formal 1,4-Dipole Precursor: Lewis Acid-Catalyzed Nucleophilic Addition with Silylated Nucleophiles.

3-Methylene-4-amido-1,2-diazetidine (MADA) was prepared for the first time via formal [2 + 2] cycloaddition of an allenamide and an azodicarboxylate. MADA worked as a formal 1,4-dipole precursor toward nucleophilic addition with various silyl enol ethers and allyltrimethylsilanes.