| This dissertation is concerned with the synthetic utility of aryl mesylates derived from phenols in various nickel (0) catalyzed homo- and cross-coupling reactions and their application to the polymer synthesis.; In PART I, highly selective nickel (0) catalyzed homo-coupling reaction of aryl mesylates is described. This reaction provides a convenient method for the synthesis of many functional symmetrical biaryls and was applied to the preparation of both well known and novel 2,2{dollar}spprime{dollar}-, 3,3{dollar}spprime{dollar}- and 4,4{dollar}spprime{dollar}-disubstituted biphenyls and other biaryls. In addition, the influence of the electronic and steric effects of substituents attached in the para, meta and ortho positions of phenols on the yield of homo-coupling of the corresponding mesylate is discussed.; The utility of this reaction is demonstrated by the efficient synthesis of four novel 2,2{dollar}spprime{dollar}-disubstituted-4,4{dollar}spprime{dollar}-dihydroxybiphenyls (i.e., 2,2{dollar}spprime{dollar}-dibenzoyl-4,4{dollar}spprime{dollar}-dihydroxybiphenyl, 2,2{dollar}spprime{dollar}-di(p-fluorobenzoyl)-4,4{dollar}spprime{dollar}-dihydroxybiphenyl, 2,2{dollar}spprime{dollar}-di(p-t- butylbenzoyl)-4,4{dollar}spprime{dollar}-dihydroxybiphenyl and 2,2{dollar}spprime{dollar}-diphenyl-4,4{dollar}spprime{dollar}-dihydroxybiphenyl). In all cases, the nickel (0) catalyzed homo-coupling of the aryl mesylates of 4-protected-2-substituted hydroquinones was used as the key reaction step.; In PART II, various nickel (0) catalyzed cross-coupling reactions based on aryl mesylates are described. These experiments also demonstrate that nickel catalysts can be used in place of the more expensive palladium catalysts in already known palladium catalyzed cross-coupling reactions.; The Ni(0) catalyzed Suzuki-type cross-coupling reaction of aryl mesylates with arylboronic acids in the presence of {dollar}rm Ksb3POsb4{dollar} is described. This novel reaction which yields unsymmetrical biaryls in good yields under mild conditions, is highly regiospecific and tolerates various functional groups.; The Ni(0) catalyzed cyanation of aryl mesylates is also described. It is demonstrated that aryl mesylates are converted to nitriles in high yields by reaction with KCN in the presence of nickel (0) catalyst in DMF. The influence of the electronic effects of para-substituents upon the yields of cyanation product and side reaction products are described. In addition, the influence of solvent, polarity, the type of catalyst, and the amount of added ligand are discussed.; The Ni(0) catalyzed cross-coupling reactions of aryl mesylates with various organometallic carbanion synthons (organotin, -magnesium and -zinc compounds) are also described. It is demonstrated that Stille-type coupling reaction based on organotin compounds results in low yields. Good to high yields of cross-coupled products are obtained by using more reactive organomagnesium and-zinc compounds as coupling partners. The Ni(0) catalyzed aromatic nucleophilic substitution reaction of aryl mesylates with heteroatom-nucleophilie (phenylthiolate anion) is also presented.; In PART III, the synthesis and characterization of functional poly(p-phenylene)s and other polyarylenes based on Ni(0) catalyzed homo-coupling of bismesylates derived from substituted hydroquinones and other dihydroxy arylenes are described. In addition, the synthetic procedures which lead to regioregular and regioirregular substituted poly(p-phenylene)s with high molecular weight are discussed. |
