Bromination reactions important in the mechanism of the Belousov-Zhabotinsky system

We investigate the kinetics of,bromination of malonic acid, bromomalonic ac id, tartronic acid, and ethanetetracarboxylic acid in 1 M sulfuric acid wit h bromine and hypobromous acid as brominating agents. In all cases the reac tion occurs via the enol form of the acid, and the reaction products are br ominated species. The possibility of bromide production in the reaction of malonic acid or bromomalonic acid with hypobromous acid can be ruled out. T hese results are important for the negative feedback loop in the Belousov-Z habotinsky reaction.