Synthesis of five-membered cyclic nitrones based on the Lewis acid-catalysed [3+2]-annulation reaction of donor–acceptor cyclopropanes with 1,4,2-dioxazoles†
Abstract
A novel synthesis of five-membered cyclic nitrones has been developed based on the Lewis acid-catalysed [3+2]-annulation reaction of D–A cyclopropanes with 1,4,2-dioxazoles. Broad substrate scope and generally good yield make this reaction useful in the preparation of nitrones. When a suitable 1,4,2-dioxazole was used, nitrone and tetrahydrofuran could be prepared in one pot with high atom economy.