tailieunhanh - Mass spectra of some azomethines of 5-amino-2-phenylindole series

The mass spectra of some azomethines of 5-amino-2-phnylindole have been recorded and their structures have been elucidated. The general fragmentations of these azomethines in mass spectra were suggested and discussed. It has shown that the main direction of fragmentation was the cleavage of C–N bond between indole ring and azomethine bond –CH=N– lead to form fragment ion at m/z 192 (direction A). | Journal of Chemistry Vol. 45 6 P. 785 - 780 2007 MASS SPECTRA OF SOME AZOMETHINES OF 5-AMINO-2-PHENYLINDOLE SERIES Received 17 April 2007 DANG NHU TAI1 NGUyEN DINH THANH1 PHAM Duy NAM2 HOANG THANH Duc3 1Faculty of Chemistry Hanoi University of Science VNU 2Vietnam-Russia Tropical Center institute of Industrial Chemistry SUMMARy The mass spectra of some azomethines of 5-amino-2-phnylindole have been recorded and their structures have been elucidated. The general fragmentations of these azomethines in mass spectra were suggested and discussed. It has shown that the main direction of fragmentation was the cleavage of C-N bond between indole ring and azomethine bond -CH N- lead to form fragment ion at m z 192 direction A . I - INTRODUCTION In the previous articles 1 - 3 we have reported about the synthesis of some azomethines of 5-amino-2-phenylindole series and the study on their IR- NMR-spectra. The metallic corrosion inhibition properties on some metals have been investigated. In order to estimate the structure of these compounds the mass spectra have been recorded and elucidated through their fragmentations. II - EXPERIMENTAL Azomethines of 5-amino-2-phenylindole series what were used in this research have been synthesized in according to the method described 1 . Their structures have the following formulas where R were m-NO2 I p-Cl II H III 3 4 -O2CH2 IV p-OCH3 V p-OH VI p-N cH3 2 VII o-OH VIII 3-oH-oCH3 X Their mass spectra were recorded on MS USA using EI method. The data of their mass Engine 5989B Spectrometer Hewlet Packard spectra were represented in table 1. 785 III - RESULTS AND DISCUSSION In the mass spectra of all of studied azomethines of this series the molecular ion peak had been always appeared with high intensities 100 in BPI . This situation could be explained that the aromatic and heteroaromatic nuclei contributed to stabilize this molecular ion. On the other hand the m z values of these peaks have been corresponded with molecular weight of .