Date of Graduation
Eberly College of Arts and Sciences
Kung K. Wang
Jeffrey L Petersen
Brian V. Popp
A synthetic pathw ay o f preparing functionalized cycloparaphenylene (CPP) bearing three evenly spaced 5,8-dim ethyoxynaphth-l,4-diyl units and tw o m acrocyclic CPP precursors has been developed. The key steps included the D iels-A ld er reaction betw een (E,E)-1,4-bis(4-brom ophenyl)- 1,3-butadiene and 1,4-benzoquinone followed by m ethylation to produce an L-shaped building block w ith tw o 4-brom ophenyl groups cis to each other exclusively, the nickel-m ediated hom ocoupling reactions to construct the m acrocyclic dim ers and trim ers, and m ild, efficient oxidative arom atization by 2,3- dichloro-5,6-dicyano- 1,4-benzoquinone (D D Q ) to furnish the functionalized CPP. A synthetic pathw ay for constructing fused carbon nanohoops w ith the two nanohoops in nanotube-like connection has also been developed. The key interm ediate with all four 4-brom ophenyl groups cis to one another in an L-shaped building block was prepared by two consecutive D iels-A ld er reactions, followed by m ethylation. The Ni(cod)2 -m ediated hom ocoupling reactions produced the m olecules that contained either tw o hydrogenated CPP, or tw o hydrogenated CPPs fused through 1,4- dim ethoxybenzene m oieties and other bent and fused nanostructures with subunits o f differing sizes o f CPPs. The structure o f a fused carbon nanohoop containing two hydrogenated CPP units was established by X -ray structure analysis and a stepw ise synthetic sequence. The structure o f a m olecule containing tw o fused carbon nanohoops com prised o f tw o hydrogenated CPPs was also established by a sim ilar stepw ise synthesis. In addition, a synthetic sequence to a functionalized [10JCPP has also been established. This synthetic pathw ay is being explored for the construction o f fused carbon nanohoops containing tw o fully arom atized CPPs.
Huang, Changfeng, "Syntheses and Structures of Functionalized Cycloparaphenylenes and Fused Cycloparaphenylene Precursors." (2016). Graduate Theses, Dissertations, and Problem Reports. 8177.