IDENTIFICATION AND DETERMINATION OF THE ISOMERIC BROMOSUBSTITUTED ANDOR CHLOROSUBSTITUTED 1,3-DIHALO-5,5-DIMETHYLHYDANTOINS USED IN DISINFECTANTS AND MOLLUSCICIDES/

Proton nuclear magnetic resonance spectrometry (H-1 NMR) was used to i dentify and quantitate the 4 isomeric bromo- and/or chloro-substituted 1,3-dihalo-5,5-dimethylhydantoins in technical-grade materials used t o prepare commercial disinfectants and molluscicides. We found that th e technical grades of bromo/chloro-substituted 1,3-dihalo-5,5-dimethyl hydantoins are mixtures of the 4 possible isomers, that interconversio n among isomers occurs in solution and can be detected by H-1 NMR, and that isomer interconversion occurs over times greater than those of t he NMR timescale.