STRUCTURAL STUDY OF MN(III) TETRAARYLPORPHYRIN COMPLEXES BY FAST-ATOM-BOMBARDMENT MASS-SPECTROMETRY

A series of 27 Mn(III)-tetraarylporphyrins bearing heterogeneous substituents on the phenyl rings at the meso positions were subjected to positive ion fast atom bombardment mass spectrometry The source spectra yielded the molecular ion and a few peaks confirmative of the chemical structure. Major processes were hydrogenolytic loss of the aryl rings or of their substituents. Molecules carrying a side-chain underwent loss of the chain either as a solution process (amide linkage) or as a gas-phase process (phenolic ether linkage). Collisonally activated dissociation mass-analysed ion kinetic energy spectroscopy allowed discrimination between the two types of fragmentation processes and some other previously unreported gas-phase reaction channels to be recognized.