title: Interconvertions between delta-lactam and delta-lactone derivatives initiated by unique transannular interactions of the rigid cyclohexane boat structure in pentacycloundecane.
abstract: The pentacycloundecane (PCU) cage structure resembles a perfect boat conformation, and for the first time unique lactam/lactone interconversions on the flagpole carbons of a cyclohexane boat structure are reported. The syntheses of a novel dihydroxy-PCU-delta-lactone and two novel N-substituted PCU-delta-lactams are reported. Hydrolysis of some of the PCU-delta-lactam compounds produced delta-lactones, and reaction of the lactones with ammonia or primary amines again produced delta-lactams. Reaction mechanisms to account for the unusual interconversion reactions induced by transannular interactions are proposed.
authors.affiliation: School of Chemistry, University of Kwazulu-Natal, Durban 4001, South Africa.
authors.forename: Hendrik G
authors.initials: HG
authors.lastname: Kruger
authors.forename: Frans J C
authors.initials: FJ
authors.lastname: Martins
authors.forename: Agatha M
authors.initials: AM
authors.lastname: Viljoen
mesh_terms: D002384:Catalysis; D003510:Cyclohexanes / Q000737:chemistry*; D007769:Lactams / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D003510:Cyclohexanes; D007769:Lactams; D007783:Lactones