Behaviour of 1,4,5-substituted tetrazolines under electron impact: unambiguous identification of tetrazolium ions by CAD/MIKE spectrometry

Abstract

The mass spectra of some 1,4,5-substituted tetrazolines were studied in order to establish the structure of the compounds. An unusual cleavage of the molecular ion of the 5-phenyl-substituted tetrazolines was observed, i.e. the loss of a phenyl radical leading to a tetrazolium ion. The tetrazolium ions undergo one or two cycloreversions, depending on whether the tetrazoline bears two similar or two different substituents on the cyclic nitrogen atoms, thus leading to the formation of one or two nitrilium ions.