A study of rearrangement processes in the mass spectra of substituted diphenyl‐ethers

An investigation of the mass spectra of a number of substituted diphenyl ethers has shown that the major fragment ions are commonly due to cleavage of the molecule into the two benzene ‘half’ fragments although in many cases the molecular ion is the most abundant species observed. Little evidence is seen of MCO or MCHO peaks in these molecules but a large number of different rearrangement processes have been observed which involve ortho‐substituents. These rearrangement ions, although in some cases not very abundant, can be diagnostic in the problem of locating substituents in the diphenyl ether nucleus.