Rapid degradation of cyclic peroxides by titanium and antimony chlorides

Abstract

First responders face extraordinary risks when dealing with organic peroxides such as TATP due to the extreme sensitivity of this class of explosives, and to a lack of a robust chemical means of safe and rapid neutralisation. The Lewis acids TiCl4 and SbCl3 have been found to demonstrate a novel degradation mechanism, with TiCl4 degrading a model cyclic peroxide in minutes when used in a two-fold excess, or ∼3 hours at half equivalence. The products cannot re-form peroxide compounds as is the case with acid degradation, suggesting the two mechanisms are fundamentally different. The Lewis acids mediate a rearrangement reaction in the cyclic peroxide backbone leading to relatively innocuous products through deactivation of oxidising O. Sub-stoichiometric TiCl4 reactions highlight a secondary reaction pathway that also leads to some oxidative chlorination products, possibly mediated by an unconfirmed titanium-oxychloride species. SbCl3 was found to exhibit similar reactivity to TiCl4, although at a slower rate. A mechanism is proposed, consistent with the observations for both stoichiometric and sub-stoichiometric quantities of TiCl4.

Peroxide Based Organic Explosives

“…The experiments showed that SbCl 3 exhibits similar reactivity to TiCl 4 , although at a slower rate. In the article also a mechanism is proposed, consistent with the observations for both stoichiometric and sub-stoichiometric quantities of TiCl 4 [28].…”

“…Pioneers of the field faced extraordinary risks when dealing with organic peroxides such as TATP due to the extreme sensitivity of this class of explosives, and to a lack of a robust chemical means of safe and rapid neutralization. Bali et al, studied degradation reactions of some peroxide compounds [28]. The Lewis acids TiCl 4 and SbCl 3 have been found to demonstrate a novel degradation mechanism.…”

Enhanced electrospray ionization mass spectrometric detection of hexamethylene triperoxide diamine (HMTD) after oxidation to tetramethylene diperoxide diamine dialdehyde (TMDDD)

“…Due to slow decomposition they should be used immediately and not stored in the laboratory. Remains should be disposed of using an appropriate procedure …”