MASS-SPECTROMETRY OF SOME C6F13-COMPOUNDS AND THEIR C6H13-ANALOGS

The 70 eV electron ionization mass spectrometric behaviour of some C6F13-compounds has been studied in detail by means of mass-analyzed ion kinetic energy spectroscopy and compared with that of the CH13-analogs. As a general trend, the incorporation of fluorine leads to a strengthening of the alkyl chain; in fact the extensive primary fragmentation processes related to the chain cleavages observed for hydrocarbon derivatives are strongly suppressed in the case of the corresponding fluorocarbons. Moreover, the interaction of fluorine with functional groups leads to unexpected decomposition processes. The -CH2-CF2- bond, often considered in condensed-phase chemistry as a weak point in the molecule, never undergoes fragmentation.