ELECTRON IMPACT MASS SPECTROMETRIC STUDIES OF 3-METHYL-1A-PHENYL-1,1-DICHLORO-1A,2,3,4-TETRAHYDRO-AZIRINO2,1-D1,5BENZOTHIAZEPINES

The mass spectrometric behaviour of five 3 -methyl-la-phenyl - 1, 1 -dichloro- la. 2,3,4- tetrahydro-azirino2, 1 -q1,5benzothiazepines has been studied with The aid of mass-analysed ion kinetic energy spectrometry. All compounds show a tendency to eliminate a chlorine atom from aziridine ring, and Then eliminate a neutral propene from The thiazepine ring to yield l,4-benzothiazine ions, or furTher eliminate a chlorine to yield 1,6-benzothiazocine ions. They could also eliminate consecutively a chlorine atom and hydrogen chloride in The samle time to undergo a ring enlargement rearrangement to yield 1,6-benzothiazocine ions, which furTher lose small molecular fragments or propyne and undergo rearrangement to give 1,4- benzothiazine ions.