Unexpected cyclization of dipyrilydl-glycoluril in the presence of formaldehyde and strong acid : a new scaffold with a potential as a receptor and synthesis of vairous calixarene precursors

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2005
Cevheroğlu, Orkun
This thesis covers combination of two independent works accomplished throughout the study. One part research is about the unexpected cyclization of Dipyridyl-glycoluril, and the other part is about synthesis of precursor calix[4]arene derivatives. In an attempted synthesis of peripherally pyridine substituted cucurbituril, an unexpected cyclized product was obtained. A careful NMR analysis followed by mass spectrometry and preliminary crystallographic analyses, helped us in resolving the structure. The structure has two quaternized pyridine functionalities and a groove suitable as a potential receptor site. In addition, just like the parent glycoluril structure, two remaining urea-derived nitrogens can be alkylated by alkyl halides. Thus, we believe this high yielding reaction may become an entry point to a new class of anion receptors. In the second work, certain important calix[4]arene derivatives were synthesized. They are the building blocks of important potential molecular, anion and cation sensing, and enzyme mimics. For these precursor molecules, functionalizations both on lower and upper rim have been studied. A careful study on NMR data has been performed and detailed investigation on the NMR data was discussed herein. Applying further one or two step procedures produces important target molecules having potential as sensors or artificial enzymes.

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Citation Formats
O. Cevheroğlu, “Unexpected cyclization of dipyrilydl-glycoluril in the presence of formaldehyde and strong acid : a new scaffold with a potential as a receptor and synthesis of vairous calixarene precursors,” M.S. - Master of Science, Middle East Technical University, 2005.