Exchange of chlorine atoms during the reaction of hypochlorous acid with 2,3-dichloropropene

Abstract

2,3-Dichloropropene reacts with [36Cl]hypochlorous acid in water in the presence of mineral acid and an excess of silver ions to give 1,3-dichloroacetone (major product) and 1,2,3-trichloropropene, both with specific activity only ca. 65% of that of the [36Cl]hypochlorous acid. 2,3-[2-36Cl]Dichloropropene reacted with inactive hypochlorous acid to give 1,3-dichloroacetone, with specific activity ca. 35% of that of the olefin. Addition of potassium [36Cl]chloride solution during the reaction with inactive substrates resulted in appreciable radioactivity in the product, whereas in the presence of freshly precipitated silver [36Cl]chloride negligible activity appeared in the product. Addition of sodium [36Cl]chloride to hypochlorous acid containing an excess of silver nitrate immediately produced radioactivity in solution. The extent of this activity depended markedly on the silver ion concentration and hardly at all on the acidity of the medium. The results are interpreted in terms of an exchange reaction involving silver chloride ion-pair aggregates.