title: Synthesis and structure of oxacalix[2]arene[2]triazines of an expanded π-electron-deficient cavity and their interactions with anions.
abstract: Novel macrocyclic anion receptors based on the principle of anion-π interactions were reported. By means of both post-macrocyclization modification protocol and the stepwise fragment coupling approach, functionalized oxacalix[2]arene[2]triazines bearing two other electron-deficient (hetero)aromatic rings on the lower rim were efficiently synthesized. The resulting oxacalix[2]arene[2]triazine macrocyclesadopt 1,3-alternate conformation, yielding therefore an expanded electron-deficient cavity or space consisting of two triazine rings and two appending aromatic rings. Spectroscopic titration study showed the selective interaction of the pentafluorophenyl-substituted oxacalix[2]arene[2]triazine with azide and fluoride in solution with the binding constants (K(1:1)) ranging from 1.33 × 10(3) to 3.52 × 10(3) M(-1).
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Sen
authors.initials: S
authors.lastname: Li
authors.forename: Shi-Xin
authors.initials: SX
authors.lastname: Fa
authors.forename: Qi-Qiang
authors.initials: QQ
authors.lastname: Wang
authors.forename: De-Xian
authors.initials: DX
authors.lastname: Wang
authors.forename: Mei-Xiang
authors.initials: MX
authors.lastname: Wang
mesh_terms: D000838:Anions / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D047250:Calixarenes / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D003500:Cyclization; D004583:Electrons; D005459:Fluorides / Q000737:chemistry*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics; D014227:Triazines / Q000138:chemical synthesis*
chemical_list: D000838:Anions; D001386:Azides; D012996:Solutions; D014227:Triazines; D047250:Calixarenes; D005459:Fluorides