Mass spectra of chloro‐substituted benzophenones

Publisher Website
Google Scholar
Abstract
The mass spectra of all three monochloro‐, seven of the dichloro‐ and two of the trichloro‐substituted benzophenones are reported. The major fragments in the spectra are due to α‐fission to oxonium ions followed by the well‐known subsequent fragmentations. The ring bearing the greater number of chlorine atoms appears to cleave more readily, with 2‐chloro substituents enhancing this tendency. There is evidence for the formation of the biphenylene ion in all monochloro and all dichloro compounds studied and for the formation of the chloro biphenylene ion in both trichloro compounds studied. In the case of 2,2′‐, 2,4‐ and 3,4‐dichlorobenzophenones evidence exists for hydrogen transfer between rings.
Keywords