Date of Graduation

2017

Document Type

Dissertation

Degree Type

PhD

College

Eberly College of Arts and Sciences

Department

Chemistry

Committee Chair

Kung K Wang

Committee Co-Chair

Robert K Griffith

Committee Member

Jeffrey L Petersen

Committee Member

Brian V Popp

Committee Member

Bjorn C G Soderberg

Abstract

Synthetic pathways for preparing furan-containing cycloparaphenylenes (CPPs) bearing 10, 12, and 15 aromatic units in the macrocyclic ring structures were developed. Several important steps used in these syntheses are the Suzuki--Miyaura cross-coupling reaction between the L-shaped building block and 2-furanylboronic ester the nickel-mediated homocoupling reaction to incorporate two and three 2,2'-bifuran-5,5'-diyl units into functionalized [6]- and [9]cycloparaphenylene (CPP) precursors. Oxidative aromatization of the precursors with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) under mild conditions led to the formation of fully aromatized furan-containing cycloparaphenylenes (CPPs).;The Diels--Alder reaction between the parent benzyne or 3,6-dimethoxybenzyne with furan-2,5-diyl units incorporated into functionalized [8]CPP macrocycle followed by reductive deoxygenation of the Diels--Alder adducts with diiron nonacarbonyl, Fe2(CO)9 led to the formation of functionalized [12]CPP macrocyclic precursors. Oxidative aromatization with DDQ produced functionalized [12]cycloparaphenylenes bearing four evenly spaced biphenyl and naphthyl units. Additionally, a synthetic pathway for preparing a functionalized [10]CPP has been developed. Tetrahydro[10]CPP was used to investigate the effect of macrocyclic ring size on the reaction rate of oxidative aromatization with DDQ.;Finally, a synthetic pathway for the construction of fused molecular nanohoops bearing two macrocyclic rings with different ring sizes by using two different 1,3-butadienes for the Diels--Alder reactions with 1,4-benzoquinone has been developed. The key intermediate in this strategy involves having four phenyl groups in cis position to one another after the second Diels--Alder reaction. This intermediate led to the formation of a fused carbon nanohoop bearing a tetrahydro[6]cycloparaphenylene (4H[6]CPP) fused to a 4H[10]CPP and a macrocycle bearing a 4H[6]CPP fused to a [6]CPP inserted with two 2,2'-bithiophene-5,5'-diyl units.

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