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Aryl mesylates can be cross coupled with organometallic carbanions in the presence of nickel catalyst to generate nitriles from phenolic oxygen. The stille-type coupling reaction gives low yields due to the slow transmetalation step of the reaction mechanism, but high yields are obtained by using strong organometallic reagents. Triflates are useful in various cross-coupling reactions but are very expensive. The substitution reaction of aryl mesylates with benzenethiolate anion is also discussed.

A new simple method of synthesizing 2,2'-diaroyl-4,4'-dihydroxybiphenyls involves 2-substituted hydroquinones' aryl mesylates, which homocouple with Ni as a catalyst. The products are obtained in a good yield in this reaction, where the aryl mesylate is activated by the electron-withdrawing nature of the benzoyl group derivatives, resulting in oxidative addition.

Aryl arenesulfonates and arylmesylates cross-couple with arylboronic acids in the presence of K3PO4 to produce unsymmetric biaryls in a regioselective manner. This Suzuki-type of reaction involves the use of Ni(O) catalyst, which is obtained from Zn and NiCl2 (dppf). The quality of the end product depends on the substituents, solvent and leaving group. This reaction is cost-effective and the aryl mesylates are not hydrolyzed easily, making it a more preferred one.

Synthesis of symmetrical biaryls from phenol-derived aryl sulfonates involves homocoupling in the presence of catalytic amounts of in situ generated zero-valent nickel catalysts. This coupling procedure efficiently prepares 3,3'-, 2,2'-, and 4, 4'-disubstituted biphenyls. Examination of the influence of substituents on the yield reveals that presence of electron-withdrawing groups in the para position increases the yield. A comparative study suggests p-fluorobenzenesulfonate group as the most reactive leaving group.

Three models having more consistent structural resemblance to the quinone form (TPQ) of a protein found in mammalian copper amine oxidase active sites are synthesized. These models differ in the nature of alkyl substituent. These quinone forms deaminate benzylamine in aqueous CH3CN, both catalytically and stoichiometrically. The pH-dependent benzenetriol to hydroxyquinone autooxidation and amine reaction with benzenetriol forms are examined to analyze aerobic autorecycling deamination.

Examines the synthetic utility of aryl mesylates derived from phenols in various transition metal-catalyzed cross-coupling reactions. Reaction pathway; Ni(O)-catalyzed cross-coupling of aryl mesylates with (tri-n-butylphenyl) stannane; Ni(O)-catalyzed cyanation of aryl mesylates.

Studies the effect of mammalian copper amine oxidases on oxidative deamination of primary amines. `Active carbonyl' cofactor; Stoichiometric substitution; Structural characterization of hydroxyquinone arylhydrazine derivatives.