The nickel complex in [Ni(TIM)]2+ where TIM is 2,3,9,10-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene macrocyclic ligand containing two conjugated N:C-C:N structural units, can serve as the oscillating catalyst in the titled system. A characteristic green color of Ni (III) species appeared periodically in the solution and the periodical changes in the optical d. were recorded. Belonsov-Zhalotinskii oscillating system, the initial concns. of the components influence the parameters and the shape of the oscillating waves. In the absence of organic substrate the catalyst itself cannot serve the organic substrate to produce oscillations. Acrylamide, acetonitrile, or H2O2 can inhibit the oscillating reaction.

Key words: REACTION MECHANISM, NITROGEN HETEROCYCLICS, OXALIC ACID, MALONIC ACID, NICKEL COMPLEX, BROMIC ACID, OSCILLATARY REACTION