Facile hydrolysis-based chemical destruction of the warfare agents VX, GB, and HD by alumina-supported fluoride reagents.

A facile solvent-free hydrolysis (chemical destruction) of the warfare agents VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate), GB (O-isopropyl methylphosphonofluoridate or sarin), and HD (2,2'-dichloroethyl sulfide or sulfur mustard) upon reaction with various solid-supported fluoride reagents is described. These solid reagents include different alumina-based powders such as KF/Al(2)O(3), AgF/KF/Al(2)O(3), and KF/Al(2)O(3) enriched by so-called coordinatively unsaturated fluoride ions (termed by us as ECUF-KF/Al(2)O(3)). When adsorbed on these sorbents, the nerve agent VX quickly hydrolyzed (t(1/2) range between 0.1-6.3 h) to the corresponding nontoxic phosphonic acid EMPA as a major product (>90%) and to the relatively toxic desethyl-VX (<10%). The latter byproduct was further hydrolyzed to the nontoxic MPA product (t(1/2) range between 2.2-161 h). The reaction rates and the product distribution were found to be strongly dependent on the nature of the fluoride ions in the KF/Al(2)O(3) matrix and on its water content. All variations of the alumina-supported fluoride reagents studied caused an immediate hydrolysis of the highly toxic GB (t(1/2) < 10 min) to form the corresponding nontoxic phosphonic acid IMPA. A preliminary study of the detoxification of HD on these catalyst supports showed the formation of the nontoxic 1,4-thioxane as a major product together with minor amounts of TDG and vinylic compounds within a few days. The mechanisms and the efficiency of these processes were successfully studied by solid-state (31)P, (13)C, and (19)F MAS NMR.