Date of Award
Doctor of Philosophy (PhD)
Richard D. Gandour
In order to study intramolecular enzyme catalysis, chemical models have been designed to quantify the proximity and orientation effects which occur in carboxylate catalyzed hydrolyses. As part of this broader study, various 2,2$\sp\prime$,7,7$\sp\prime$-tetrasubstituted 1,1$\sp\prime$-ethynylenedinaphthalenes are synthesized from 2,7-dihydroxynaphthalene. Two different strategies are used to obtain the title compounds. The first strategy involves palladium-mediated couplings between electron-poor aryl iodides and electron-rich arylethynes and allows synthesis of unsymmetrical binaphthylethynes. The second approach couples two 2,7-disubstituted naphthalenes with tetrachlorocyclopropene in the presence of aluminum chloride, but only symmetrical binaphthylethynes are obtained. During the course of this work, a number of 1,2,7-trisubstituted naphthalenes, some of them previously unknown, have been prepared. Several new or improved procedures have also been developed, most notably the monomethylation of 2,7-naphthalenediol in a two solvent system, a new three-step preparation of methyl 7-methoxy-2-naphthoate, and a new two-step synthetic method for the acyl $\to$ ethynyl conversion in electron-rich aromatic rings. Both strategies produce several new binaphthylethynes, two of which are unsymmetrical. These two compounds represent the first examples of this type of molecule. Through NMR spectroscopic techniques and X-ray diffraction, a large amount of spectral and structural data on naphthalenes has been assembled and discussed. In addition, a literature review of the previous syntheses of dinaphthylethynes is included.
Prince, Philippe, "Syntheses, Structures, and Characterizations of 2,2',7,7'-Tetrasubstituted 1,1'-Ethynylenedinaphthalenes." (1993). LSU Historical Dissertations and Theses. 5539.