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

Highly functionalized 1,5,2-dioxazinanes could be smoothly produced a Sc(OTf)-catalyzed chemoselective [3 + 3] cycloaddition of various -arylnitrones with a series of donor-acceptor oxiranes. This reaction involves generation of 1,3-dipoles through Sc(OTf)-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.