Site of Chlorine Interaction With a Cation-Exchange Resin (Chelex-100)

Abstract

X-Ray photoelectron spectroscopy, ¹³C and ¹H solution-state n.m.r., and ¹³C solid-state n.m.r. were used in chlorination studies on compounds, which act as models for the exchange group and the styrene divinylbenzene copolymer backbone of Chelex-100, to determine the site and mechanism of chlorine attack. Results indicate that the resin cleaves upon chlorination, and a cleavage mechanism, involving initial attack by chlorine on the exchange group imine nitrogen electron lone pairs, is proposed. The N-halo quaternary species formed loses a molecule of hydrogen chloride to give a Schiff base, which undergoes hydrolysis to an aldehyde and an ammonium salt.