Specific and random processes in the fragmentation of cyclohexanol

The mass spectra of cyclohexanol and eleven deuterated analogues have been studied. Detailed mechanisms, consistent with peak intensity and defocused metastable abundance data, have been proposed for the loss of water from the molecular ion and for the subsequent loss of a methyl radical. The importance of specific eliminations and the absence of any processes involving complete hydrogen atom scrambling in these fragmentations has been demonstrated. Scrambling has also been shown to be absent in the formation of the base peak m/e 57, the C₃H₅O]⁺ ion.