title: Copper(I) catalyzed diastereoselective multicomponent synthesis of spiroindolo-pyrrolidines/-imidazolidines/-triazolidines from diazoamides via azomethine ylides.
abstract: Investigations of regio-, chemo- and diastereoselective studies on three- as well as four-component reactions using diazooxindoles, imines, aldehydes, amines, alkenes, alkynes or diazenes in the presence of copper(I) thiophene-2-carboxylate are performed to furnish spiroindolo-pyrrolidine/-imidazolidine/-triazolidine ring systems in good yields. A mixture of products was obtained when unsymmetrical alkenes were used as dipolarophiles. This study demonstrates the successful generation of intermolecular azomethine ylides from copper(I) carbenoids and their subsequent 1,3-dipolar cycloaddition reactions with various dipolarophiles, such as olefins (C=C), imines (C=N), diazenes (N=N) in a stereoselective manner. Single-crystal X-ray analyses were performed to establish unambiguously the structure and stereochemistry of spiroheterocyclic ring systems.
authors.affiliation: School of Chemistry, Bharathidasan University, Tiruchirappalli - 620024, India. muthu@bdu.ac.in.
authors.forename: Sengodagounder
authors.initials: S
authors.lastname: Muthusamy
authors.forename: Singaravelan Ganesh
authors.initials: SG
authors.lastname: Kumar