Date of Award

2-1-1989

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Abstract

There have been several recent attempts to synthesize a one-dimensional graphite-like polymer, namely poly(peri-naphthalene) (PPN). All of these approaches involved pyrolysis of a substituted perylene monomer to yield a polymer that exhibited characteristics not unlike those expected for PPN. The process of going from a monomer directly to an intractable polymer raises questions regarding processibility. A potential means to avoid the question is to synthesize a soluble/processible precursor polymer and subsequently convert this polymer to the desired PPN. This is the goal of the research reported herein.To successfully approach such a project, studies with appropriate model compounds were deemed necessary. Binaphthyls and ternaphthyls appeared to meet the criterion for such compounds, since they resemble a precursor polymer to PPN. Three binaphthyls and three ternaphthyls were synthesized using Grignard aryl coupling promoters. These model compounds were then exposed to high and low temperature molten salts. The binaphthyls isomerized in the low temperature melts and cyclodehydrogenated to form perylene (a dimeric form of PPN) in the high temperature melts. 1,1$\sp\prime$:5$\sp\prime$,1$\sp{\prime\prime}$-Ternaphthyl yielded isomerization products upon treatment with the low temperature melt and terrylene and perylene in the high temperature melts. The presence of terrylene supports the binaphthyl studies, i.e., cyclodehydrogenation to yield perylene under high temperature molten salt conditions. The presence of perylene indicated that fragmentation of naphthyl moieties may occur in such media.Work then focused on polynaphthalenes, since they represent direct percursors to PPN. Many different isomers of polynaphthalene were prepared via Grignard aryl coupling routes including several isomers which employed an active form of magnesium in the preparation of the Grignard adduct. Two polynaphthalenes with different regiochemistry were prepared from the same monomer (i.e. a non-symmetric 1,6-dibromonaphthalene) by employing different Grignard aryl coupling promoters. 1,4-Polynaphthalene and 1,5-polynaphthalene were subsequently added to high temperature molten salts in order to obtain PPN. The product contained a benzene soluble portion that contained perylene, terrylene, and quaterrylene. The presence of these three compounds may well be the result of fragmentation, just as was observed with the ternaphthyls under similar conditions. The detection of the lower homologs, the high thermal stability as well as other factors strongly indicated that PPN or at least a material very similar to PPN had indeed been prepared.

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