Determination of the Characteristics of the Molecular Structure of Trialkyl Phosphates by the Joint Application of Electronic Ionization Mass Spectra with Registration of Positive Ions and Negative Ions of Resonance Coupling

Trialkylphosphates are of considerable interest from the military-chemical point of view as precursors of highly toxic organophosphorus toxicants, possible products of their decontamination, complexing agents in processes of reprocessing of used nuclear fuel, etc. Meanwhile, the development of ways to identify these substances is still in its infancy. In addition, trialkylphosphates are an interesting subject for the search of a solution to the analytical problem of establishing the structure of O-alkyl fragments in molecules of M(O) (OR)_n esters of multibasic acids, where M is the central atom (central core), n is the basicity of the acid, R are alkyl radicals with an unknown and in general case different number of carbon atoms in each of them. No general solution to this problem could be found in the book sources. The aim of this work is to develop an algorithm for in-depth identification of trialkyl phosphates, which includes establishing the belonging of the investigated substance to this class, as well as a general and reliable method for determining the number of carbon atoms in each of the O-alkyl radicals of the investigated substances. On the basis of the revealed regularities of the decay of positive molecular ions of trialkyl phosphates, as well as negative ions of resonant capture of electrons of the same compound obtained under conditions of electron ionization, an algorithm for in-depth identification of trialkyl phosphates is proposed, which includes establishing the belonging of the investigated substance to this class, as well as a general and reliable method determining the number of carbon atoms in each of the O-alkyl radicals of the substance molecule.

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