Abstract: The electron impact mass spectra of the series of title compounds, double Schiff base, has been studied.Owing to the common parent molecular structure, they undergo certain subsequence cleavage paths.All of these cleavages were discussed in detail.Among which the most interesting one was the cleavage, from molecule (OE⁺) ion to an OE⁺ fragment ion, in which several processes concomitantly took place with r-Hrearrangement, electron transfer, double bond migration and ion reconstruction.The evidences of the mentioned cleavages were investigated by monitoring the product ions via experiments of high resolution MS, isotopic exchanging operation, link scan technology and coilission induced dissociation (CID).

Key words: Double Schiff bases, Molecular structure rearrangement, Electron impact MS, Link scan, Collisional induced dissociation