Ankara : The Department of Chemistry and the Graduate School of Engineering and Science of Bilkent University, 2011.Thesis (Master's) -- Bilkent University, 2011.Includes bibliographical references leaves 68-74.The general objective of this thesis is to explore the ability of cucurbit[n]uril (CB[n])
(n= 6,7,8) homologues to form nano-structured supramolecular assemblies with
various organic guests through self-sorting, self-assembly and recognition.
In the first part of the thesis, the selectivity and recognition properties of
CB[n] homologues towards a ditopic guest have been investigated. The guest was
synthesized through Cu(I)-catalyzed click reaction between the salts of N,N'-bis-(2-
azido-ethyl)-dodecane-1,12-diamine and propargylamine and contain two chemically
and geometrically distinct recognition sites, namely, a flexible and hydrophobic
dodecyl spacer and a five-membered triazole ring terminated with ammonium ions.
Complex formation between the guest and CB[6], CB[7] and CB[8] in the ratios of
1:2, 1:1 and 1:1, respectively, was confirmed by 1H NMR spectroscopy and mass
spectrometry. It was also revealed that CB[n] homologues have ability to self-sort
and recognise the guests according to their chemical nature, size and shape. Kinetic
formation of a hetero[4]pseudorotaxane via sequence-specific self-sorting was
confirmed and controlled by the order of the addition.
In the second part, the effect of CB[n] homologues on the dissolution and the
photophysical properties of non-ionic conjugated polymers in water were
investigated. A fluorene-based polymer, namely, poly[9,9-bis{6(N,N
dimethylamino)hexyl}fluorene-co-2,5-thienylene (PFT) was synthesized via Suzuki
coupling and characterization was performed by spectroscopic techniques including
1D and 2D NMR(Nuclear Magnetic Resonans), UV–vis, fluorescent spectroscopy,
and matrix-assisted laser desorption mass spectrometry (MALDI-MS)(Matrix
Assisted Laser Desorption/Ionization Mass Spectroscopy ). The interaction of CB[6],
CB[7] and CB[8] with PFT have been investigated and it was observed that only CB[8] among other CB homologues forms a water-soluble inclusion complex with
PFT. Furthermore, upon complex formation a considerable enhancement in the
fluorescent quantum yield of PFT in water was observed. The structure of resulting
PFT@CB[8] complex was characterized through 1H-NMR and selective 1DNOESY(The
Nuclear Overhauser Enhancement Spectroscopy) and further
investigated by imaging techniques (e.g. AFM(Atomic Force Microscopy),
SEM(Scanning Electron Microscopy), TEM(Transmission Electron Microscopy) and
fluorescent optical microscopy) to reveal the morphology. The results suggested that
through CB[8]-assisted self-assembly of PFT polymer chains vesicle-like
nanostructures formed. The sizes of nanostructures were also determined using
dynamic light scattering (DLS(Dynamic Light Scattering)) measurements.Artar, MügeM.S
