Cycloaddition of N-arylnitrones with donor–acceptor oxiranes via C–C bond cleavage to construct 1,5,2-dioxazinanes

Abstract

Highly functionalized 1,5,2-dioxazinanes could be smoothly produced via a Sc(OTf)₃-catalyzed chemoselective [3 + 3] cycloaddition of various N-arylnitrones with a series of donor–acceptor oxiranes. This reaction involves in situ generation of 1,3-dipoles through Sc(OTf)₃-catalyzed C–C bond cleavage of oxiranes and moderate to high yields were obtained for most substrates. This transformation features C–C bond cleavage of donor–acceptor oxiranes, accessible starting materials and mild reaction conditions.