Effects of halogen atoms on the mass spectra of some 3-phenylpropionyl halides

The mass spectra of the title compounds have been studied by use of deuterium labelling. The character of the halogen atom appears to have a marked influence on the fragmentation pathways. It is shown that the acyl halide group may react with the different active atoms in the molecular ion—the α- and β-hydrogen atoms—as well as with the phenyl ring.