404-28-4Relevant academic research and scientific papers
Unique para-effect in electron ionization mass spectra of bis(perfluoroacyl) derivatives of bifunctional aminobenzenes
Tretyakov, Kirill V.,Todua, Nino G.,Borisov, Roman S.,Zaikin, Vladimir G.,Stein, Stephen E.,Mikaia, Anzor I.
body text, p. 2529 - 2532 (2011/12/02)
A new kind of 'para-effect' under electron ionization (EI) conditions has been discovered for a series of bis(perfluoroacyl) derivatives of o-, m- and p-phenylenediamines, -hydroxybenzeneamines and -mercaptobenzeneamines of a common structure RCOX-C6H4-NHCOR (X=NH, S, O; R=CF3, C2F5, C3F7). Only the para-isomers showed successive loss of a radical RCO? and a molecule RCN, leading to very intense peaks in the EI spectra. The composition and the origin of the [M-COR-NCR]+ ions were confirmed by exactmassmeasurements and linked scan experiments. The proposedmechanism of their formation takes into account likely para-quinoid structures of the precursor ions. A similar rearrangement has not been observed for para-isomers in the series of bis(perfluoroacyl) derivatives of benzenediols, mercaptophenols and dimercaptobenzenes.
