EVALUATION OF A NOVEL DECHLORINATION REACTION AS AN ANALYTICALLY USEFUL DERIVATIZATION REACTION .1. STOICHIOMETRY, MECHANISM AND YIELD OPTIMIZATION

A novel reaction for the dechlorination of polychlorinated biphenyls ( PCBs) as well as most other chlorinated aromatic and aliphatic compoun ds is evaluated and discussed in terms of its potential for analytical purposes. The active dechlorinating agent is prepared through the rea ction of molten sodium or potassium with polyethylene glycols (MW >200 ), in the absence of oxygen, to form the corresponding alkali metal gl ycolate, a powerful nucleophilic agent. Special emphasis is given to t he mechanistic aspects of the reaction and thier importance in terms o f achieving high and reproducible yields with analytical quantities of substrate, in short periods of time. The contribution of the techniqu es: ESR, NMR, IR, UV, MS, GC-ECD, LC-EC, CIDNP-NMR, conductimetry and chloride analysis (amperometric) in elucidating the reaction mechanism and providing valuable kinetic data is illustrated. This reaction can potentially be applied to the determination of PCBs in waste oils.