Structurel Analysis of Tetrapyrroles by Hydrogen Chemical Ionization Mass Spectrometry

Article abstract of DOI:10.1021/ac00236a016

The H2 chemical ionization mass spectra of several standard porphyrins have been determined.Fragmentation proceeds via hydrogenation yielding porphyrinogens, followed by cleavage at the meso (bridge) positions to produce mono-, di-, and tripyrrolic ions.Secondary fragmentation by cleavage of substituent groups attached to the pyrrole rings may then occur.Identification of these fragments and the corresponding molecular ions produces considerable structural information on the parent molecule.In certain cases these data are sufficient to distinguish porphyrin type (positional) isomers.In addition information of substituents at meso positions may be retained.