Templated Synthesis of Glycoluril Oligomers and Monofunctionalized Cucurbit[6]uril Derivatives
| dc.contributor.advisor | Isaacs, Lyle D | en_US |
| dc.contributor.author | Lucas, Derick | en_US |
| dc.contributor.department | Chemistry | en_US |
| dc.contributor.publisher | Digital Repository at the University of Maryland | en_US |
| dc.contributor.publisher | University of Maryland (College Park, Md.) | en_US |
| dc.date.accessioned | 2012-02-17T06:54:26Z | |
| dc.date.available | 2012-02-17T06:54:26Z | |
| dc.date.issued | 2011 | en_US |
| dc.description.abstract | The molecular recognition properties exhibited by molecular containers have inspired supramolecular chemists to generate diverse and specialized macrocycles. The family of hosts known as cucurbiturils (CB[n]) have become a popular platform for molecular recognition due to their high binding affinities and selectivity in water. As CB[n] branch into increasingly complex applications it becomes important to find efficient pathways to prepare monofunctionalized CB[n] derivatives bearing reactive functional groups. Chapter 1 presents a literature review of the synthesis, properties, mechanism of formation, and applications of the CB[n] family. We use this background information to explain our key hypothesis, that templated reactions offer potential routes to obtain glycoluril oligomer building blocks that allow the preparation of monofunctionalized CB[n] compounds. Chapter 2 describes the templated synthesis of glycoluril hexamer (<bold>6C</bold>) in a one step synthetic procedure on the gram scale using the <italic>p</italic>-xylylenediammonium ion (<bold>II-11</bold>). Hexamer <bold>6C</bold> undergos cyclization with (substituted) phthalaldehdyes <bold>II-12</bold>, <bold>II-14</bold>, <bold>II-15</bold>, <bold>II-18</bold> under acidic conditions at room temperature to deliver monofunctionalized CB[6] derivatives <bold>II-13</bold>, <bold>II-15</bold>, <bold>II-16</bold>, and <bold>II-19</bold>. Furthermore, the reaction kinetics for CB[6] cyclization between hexamer and formaldehyde or phthalaldehyde is influenced by the size and shape of ammonium ion templates. The larger size of the <italic>p</italic>- xylylenediammonium ion (<bold>II-11</bold>) allows it to act as a negative template by discouraging transformation of hexamer and paraformaldehyde to form CB[6]. However, <bold>II-11</bold> and hexanediammonium ion (<bold>II-20</bold>) act as positive templates during the reaction of <bold>6C</bold> and phthalaldehyde <bold>II-12</bold> by giving (±)-<bold>II-21</bold> as an intermediate along the mechanistic pathway to CB[6] derivative <bold>II-13</bold>. Finally, a fluorescence turn-on assay was investigated using the fluorophore and metal-ion binding (e.g., Eu3+) of naphthalene- CB[6] derivative <bold>II-19</bold>. The synthesis of monofunctionalized CB[6] derivatives in high yields has broad implications toward tailor-made approaches to CB[n] derived functional systems in the future. Chapter 3 describes the high yield synthesis of glycoluril pentamer (<bold>5C</bold>) by the 3,5- dimethylphenol induced fragmentation of bis-ns-CB[10] under acid conditions. The access to large quantities of 5C and 6C and previously reported tetramer <bold>III-4</bold> allowed for a comparison of host-guest recognition properties of acyclic CB[n]-type receptors toward alkaneammonium ions in water. | en_US |
| dc.identifier.uri | http://hdl.handle.net/1903/12303 | |
| dc.subject.pqcontrolled | Organic chemistry | en_US |
| dc.subject.pqcontrolled | Chemistry | en_US |
| dc.subject.pquncontrolled | Cucurbituril | en_US |
| dc.subject.pquncontrolled | glycoluril oligomers | en_US |
| dc.subject.pquncontrolled | host-guest systems | en_US |
| dc.subject.pquncontrolled | Macrocycles | en_US |
| dc.subject.pquncontrolled | Supramolecular | en_US |
| dc.subject.pquncontrolled | template | en_US |
| dc.title | Templated Synthesis of Glycoluril Oligomers and Monofunctionalized Cucurbit[6]uril Derivatives | en_US |
| dc.type | Dissertation | en_US |
Files
Original bundle
1 - 1 of 1