Activated sterically strained C=N bond in N-arylsulfonyl-p-quinone mono- and diimines - VIII. Mass spectra of N-arylsulfonyl-p-quinone mono- and diimines

Mass spectra of N,N'-bisarylsulfonyl-1,4-benzoquinone diimines, N-arylsulfo nyl-1,4-benzoquinone monoimines, and N-arylsulfonyl-1,4-naphthoquinone mono imines were investigated. The mass spectra of N-arylsulfonyl-1,4-quinone mo no- and diimines containing a sterically shielded nitrogen, and consequentl y an activated C=N bond, have an important feature differing from the mass spectra of common quinone imines: In the spectra of the activated quinone i mines appear [M+](+) ions due to addition of a hydrogen atom to the molecul ar ion of the quinone imine with formation of sterically unstrained ion of quinolide structure.