Electron impact studies. XLVIII. Specific hydrogen-rearrangements in the mass spectra of ortho-alkoxyanils.

The mass spectra of anils with ortho-alkoxyl substituents in the aromatic ring derived from the aldehyde contain pronounced peaks prod- uced by C=N bond cleavage accompanied by one and/or two hydrogen transfers to the nitrogen-containing fragment. Deuterium-labelling studies show that the hydrogen atoms involved are those attached to the α-carbon (α to oxygen) of the alkoxyl group. The extent of the hydrogen rearrangements may be altered by the addition of further substituents to the aromatic rings.