The room temperature chemistry of organo-sulfur esters with NaX zeolite

Abstract

Small organo-sulfur esters, which are common alkylating agents, are highly toxic compounds and have been proposed as possible chemical warfare agents. Previous studies have shown that dry, high Al content, X type zeolites have tetrahedral Al centers that exhibit nucleophilic properties that are of interest in chemical decontamination. This work examines the nucleophilic chemistry of representative small organo-sulfur esters with tetrahedral Al centers in NaX zeolite. Two sulfite esters and a sulfate and sulfonate ester were chosen as representatives. The chemistries of all representatives with the tetrahedral Al centers of NaX were found to be remarkably similar, namely the alkylation of the O atoms of the Al tetrahedra on the supercage surface of the zeolite to form a framework alkoxy species and the sodium salt of the acid of the corresponding organo-sulfur ester. Partial hydrolysis of the products was found, with the formation of the alcohol from the framework alkoxy specie and a Brønsted acid tetrahedral Al site in the zeolite. No hydrolysis of the anions of the salts was observed.