DABCO‐Mediated [4+1] Cycloaddition of β,β‐Dihalo Peroxides with Sodium Azide toward Isoxazoles

Abstract The isoxazole skeleton is one of key structural motifs, which displays widespread applications in drugs, agriculture, and synthetic intermediates. Herein, we disclose the DABCO‐mediated [4+1] cycloaddition of β,β‐dihalo peroxides and sodium azide for synthesis of multisubstituted isoxazoles. The cycloaddition proceeds through the formation of N−C and N−O bonds. This method shows excellent regioselectivity and good scalability.