Bifunctional Ion Exchange Resin with Thiol and Quaternary Ammonium Groups for the Sorption of Arsenate

A bifunctional resin with thiol and quaternary ammonium groups was prepared from a macroporous strongly basic anion exchange resin of the styrene-divinylbenzene type. The key step of the synthesis is the reaction of the quaternary benzyltrimethylammonium group of the ion exchange resin with suitable sulfur-containing nucleophiles. Three synthetic routes are described: direct conversion to thiol with sodium sulfide, reaction with potassium O-ethyl dithiocarbonate followed by decomposition of the dithiocarbonate with ammonia or acid and conversion to polymeric isothiuronium salt by the reaction with thiourea and subsequent alkaline hydrolysis to thiol. Sorption of arsenate on thiol resin and its Fe(III) complex was studied.

An Application of the Amidomethylation (Tscherniac-Einhorn) Reaction in Dye Synthesis

The amidomethylation (Tscherniac-Einhorn) reaction of the anthraquinones I-III (R = II) was examined in an attempt to introduce 3-halogenopropionamidomethyl groups into dyes for subsequent conversion into isothiuronium salt dyes. Methods described in the literature using 3-halogenopropionamides or propionitriles and various formaldehyde sources gave poor yields due to the reaction of formaldehyde with the anthraquinones. Satisfactory methods have been developed using bis(chloromethyl)ether to amidoalkylate I-III (R = H). Reaction of the 3-bromo- or 3-iodopropionamido-methyl derivatives of I-III (R = H) with thiourea or tetramethylthiourea gave poor yields of unstable isothiuronium salts, which were unsatisfactory wool dyes.