Dealkylation of chemical weapon agents and pesticides with group 13 salen compounds

Group 13 chelates incorporating boron and aluminum deactivated the chemical warfare agents (CWAs) VX, sarin (GB), soman (GD), and the pesticide, diazinon, under mild conditions. The deactivation occured through elimination of alkyl bromide resulting in solid products containing a robust Al-O-P or B-O-P linkage. The Group 13 chelate deactivation methodology produces non-toxic, easily disposable solid proudcts after combination with CWAs. In previous studies the group 13 chelates were found to be active for a wide range of organophosphates, organophosphonates, and organophosphinates (OPs). Thus, the compounds could be used as a deactivating agent for a wide range of problematic compounds possessing P-O-C linkages, including, CWAs, pesticides, and plasticizers. The majority of the chelate compounds are of the general formula: LBX, L(BX ₂)₂ and LA1X where L = an inexpensive, easily prepared Schiff base chelate and X = Cl and Br. This article will describe the range of compounds that can be used in the dealkylation reaction. The primary focus will be on chelates of the Salen class (Salen=N,N′- alkylene(or arylene)bis(salicylideneimine)), but a wider of range of chelates could be used for the reaction as this review will demonstrate.