title: Piperazine bridged resorcinarene cages.
abstract: The one-pot Mannich condensation of resorcinarenes with piperazine and an excess of formaldehyde under high dilution conditions results in a helical cage, namely, a covalently linked dimer of two resorcinarenes connected via four piperazine bridges in yields ranging from 20 to 40%. The compounds were analyzed by NMR spectroscopy, ESI mass spectrometry, and single crystal X-ray diffraction. The helical cages can encapsulate small guest molecules by adapting the cavity volume by changing the helical pitch according to the guest size.
authors.affiliation: NanoScience Center, Department of Chemistry, University of Jyväskylä, P.O.Box 35, 40014 Jyväskylä, Finland.
authors.forename: N Kodiah
authors.initials: NK
authors.lastname: Beyeh
authors.forename: Arto
authors.initials: A
authors.lastname: Valkonen
authors.forename: Kari
authors.initials: K
authors.lastname: Rissanen
mesh_terms: D047250:Calixarenes / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008968:Molecular Conformation; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D000077489:Piperazine; D010879:Piperazines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D010879:Piperazines; C466160:resorcinarene; D047250:Calixarenes; D000077489:Piperazine; D010649:Phenylalanine