Mass spectra of 1- and 2a-substituted 1,3,5,7-tetramethyl-2,4,6,8-tetrathiaadamantanes

A comparative analysis was made of the mass spectra of monosubstituted 1,3,5,7-tetramethyl-2,4,6,8-tetrathiaadamantanes (TMITA). It is shown that the pathways of monomolecular fragmentation depend on the character of the substituent and the isomeric form of the TMTTA. The principal lines in the mass spectra of the investigated compounds indicate the occurrence of competitive processes of fragmentation of the molecular ions (M⁺) with detachment of the substituent from the M⁺ ion or with cleavage of the cellular structure. The first process makes it possible to form a judgement regarding the mechanism of the fragmentation of the molecular ion and the site of primary localization of the charge on the fragment ions as a function of the donor—acceptor properties of the substituents, and the second process enables one to form a judgement regarding the character of the fragmentation of the cellular structures of the various isomeric forms.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 748–752, June, 1978.