title: Supramolecular assembly of 2,7-dimethyldiazapyrenium and cucurbit[8]uril: a new fluorescent host for detection of catechol and dopamine.
abstract: The formation of a highly stable inclusion complex between 2,7-dimethyldiazapyrenium (Me(2)DAP(2+)) and the cucurbit[8]uril host (CB8) was demonstrated by X-ray crystallography; MALDI-TOF mass spectrometry; and (1)H NMR, electronic absorption, and emission spectroscopy. The equilibrium association constant was determined to be 8.9(+/-0.2)x10(5) L mol(-1) from UV-visible data and 8.4(+/-1.5) x 10(5) L mol(-1) from fluorescence data. The Me(2)DAP(2+).CB8 inclusion complex acted as a host to bind compounds containing aromatic pi-donor moieties (D), such as catechol and dopamine. This point was demonstrated by (1)H NMR spectroscopy, and electrochemical and emission measurements. Fluorescence detection of the Me(2)DAP(2+).D.CB8 ternary complexes was evident in aqueous solution and on the surface of silica particles, to which fluorescent diazapyrenium units had been covalently immobilized.
authors.affiliation: Center for Supramolecular Science, Department of Chemistry, University of Miami, Coral Gables, FL 33124-0431, USA.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Sindelar
authors.forename: Mabel A
authors.initials: MA
authors.lastname: Cejas
authors.forename: Françisco M
authors.initials: FM
authors.lastname: Raymo
authors.forename: Weizhong
authors.initials: W
authors.lastname: Chen
authors.forename: Samantha E
authors.initials: SE
authors.lastname: Parker
authors.forename: Angel E
authors.initials: AE
authors.lastname: Kaifer
mesh_terms: D001952:Bridged-Ring Compounds / Q000737:chemistry*; D002396:Catechols / Q000032:analysis*; D018360:Crystallography, X-Ray; D004298:Dopamine / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D011721:Pyrenes / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D001952:Bridged-Ring Compounds; D002396:Catechols; D004298:Dopamine; D005456:Fluorescent Dyes; D007093:Imidazoles; D011721:Pyrenes; C515252:2,7-dimethyldiazapyrenium; C507198:cucurbit(8)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils; C034221:catechol