Vinyl azide with a pendent diene can undergo thermal decomposition to a related azirine intermediate, which was used immediately in an intramolecular aza-Diels–Alder reaction to furnish an aziridine-containing trans-fused tricyclic core structure with excellent stereoselectivity. The method provides a facile entry to complex polycyclic alkaliods which can be further elaborated by ring-opening reactions and ring expansion of the aziridine moiety, as well as by dihydroxylation of the alkene group.

Vinyl azide with a pendent diene can undergo thermal decomposition to a related azirine intermediate, which was used immediately in an intramolecular aza-Diels–Alder reaction to furnish an aziridine-containing trans-fused tricyclic core structure with excellent stereoselectivity. The method provides a facile entry to complex polycyclic alkaliods which can be further elaborated by ring-opening reactions and ring expansion of the aziridine moiety, as well as by dihydroxylation of the alkene group.

N-Aryl-N-allyl-bis-functionalized amino-1-sulfonyl-1,2,3-trizoles undergo rhodium-catalyzed cyclization reactions and subsequent hydrolytic cleavage of the sulfonyl imine to give two structurally distinct N-heterocycles, 3-indolyl aldehydes and 3-azabicyclo[3,1,0]hexyl aldehydes. The product ratio can be tuned by varying the electronic properties of the two functional groups attached to the N atom. Based on these findings, two efficient and general methods for the synthesis of highly valuable 3-indolyl aldehydes and 3-azabicyclo[3,1,0]hexyl aldehydes have been developed.

An efficient and convenient synthesis of α-allyl cyclic amidines has been achieved by applying a novel cascade reaction. Copper(I)-mediated in situ N-sulfonyl ketenimine formation from the reaction of a terminal alkyne with sulfonyl azide is followed by an intramolecular nucleophilic attack on the central carbon atom by an allylic tertiary amine, and then an aza-Claisen rearrangement takes place through a chair transition state to furnish the titled amidines with complete stereocontrol.

An efficient and convenient synthesis of α-allyl cyclic amidines has been achieved by applying a novel cascade reaction. Copper(I)-mediated in situ N-sulfonyl ketenimine formation from the reaction of a terminal alkyne with sulfonyl azide is followed by an intramolecular nucleophilic attack on the central carbon atom by an allylic tertiary amine, and then an aza-Claisen rearrangement takes place through a chair transition state to furnish the titled amidines with complete stereocontrol.