Mass spectrometric study of some ortho- chloro benzene derivatives by electron impact

A mass spectrometer of the type Atals (CH-4) is used in combination with de convoluted first differential (DFD) technique in order to determine the ionization and appearance energies of the following ions: 1- (M)+, (M-Cl)+ and (M-HCl)+ ions produced from Chloro benzene. 2- (M+, (M-CO)+, (M-Cl)+ and (M-CO-Cl)+ ions produced from o-Chloro phenol. 3- (M+, (M-HNC)+, (M-Cl)+ and (M-HNC-Cl)+ ions produced from o-Chloro aniline. 4- (M+, (M-H)+, (M-H)+, (M-H-Cl)+ and (M-H-CO-Cl)+ ions produced from o-Chloro benzaldehyde. ;The relative intensities at different electron energies for the prominent ions in the mass spectra of the studied compounds are measured and discussed. The probable mechanistic pathways for the formation of the prominent ions obtained from the four precursors are also reported and discussed