Controllable Lewis Base-Catalyzed Three-Component Domino Reactions of Dioxazolones, Morita–Baylis–Hillman (MBH) Carbonates, and Alcohols/Amines

Herein, we develop a novel Lewis base-catalyzed three-component divergent domino reaction of dioxazolones, Morita–Baylis–Hillman (MBH) carbonates, and alcohols/amines. On one hand, tertiary amine (triethylamine) operates as a dual nucleophilic catalyst to activate MBH carbonates and concurrently triggers the Lossen rearrangement, yielding functionalized carbamates. On the other hand, primary and secondary amines serve as substrates to generate low-reactivity ring-opened intermediates that can be efficiently intercepted by MBH carbonates to afford O -carbamoyl hydroxamates via an interrupted Lossen rearrangement. Overall, this protocol features transition-metal-free conditions and a broad substrate scope.