Fragmentation of Enamides Derived from 6,7-Dimethoxy-4-methyl-2H-1,3-benzothiazin and 3,4-Dihydro-6,7-dimethoxy-1-methylisoquinoline

Article abstract of DOI:10.1002/oms.1210240918

The elctron impact mass spectra of several enamides have been examined.The enamides were prepared by reaction of aroyl halides with 6,7-dimethoxy-4-methyl-1,3-benzothiazin, and with 3,4-dihydro-6,7-dimethoxy-1-metylisoquinoline.The fragmentation pathways that have been proposed are supported by ion composition determinations and by mass-analysed ion kinetic energy spectrometry experiments carried out on the molecular ions and major fragment ions.The spectra are characterized by a loss of carbon monoxide from the molecular ion of each compound, a process which is accompanied by migration of the aryl group.