Products of low potential energy in mass spectra as a consequence of ion–dipole attractions: some neopentyl compounds

Abstract

The 12.0 eV mass spectra of five neopentyl derivatives [(CH₃)₃CCH₂Z;Z = OH, OCH₃, NH₂, NHCH₃, and N(CH₃)₂] are reported. The competition between simple α-cleavage, single, and double hydrogen transfer reactions is discussed in mechanistic and energetic terms. Double hydrogen transfer occurs for Z = OCH₃ and NH₂, giving rise to the unusual daughter ions (CH₃)₂OH⁺ and CH₃NH₃⁺, respectively. The behaviour of the ionised neopentyl compounds is compared with that of the homologous isobutyl species, for which similar rearrangements have been previously reported.