TY - JOUR
T1 - Unexpected fragmentation of β-substituted meso-tetraphenylporphyrins induced by high-energy collisional activation
AU - Domingues, M. Rosario M.
AU - Marques, M. Graça O.S.
AU - Alonso, Cristina M.A.
AU - Neves, M. Graça P.M.S.
AU - Cavaleiro, J. A.S.
AU - Ferrer-Correia, A. J.
AU - Nemirovskiy, Olga V.
AU - Gross, Michael L.
N1 - Funding Information:
Research at Washington University was supported by the National Centers for Research Resources of the NIH (grant no. P41RR00954).
PY - 2002/12
Y1 - 2002/12
N2 - The protonated molecules and radical cations of meso-tetraphenylporphyrins with β-pyrrolic substituents, when formed by fast atom bombardment (FAB) and subjected to high-energy collisions, give rise to unexpected fragment ions. The reaction involves hydrogen migration from the ortho position of the phenyl ring to the α atom of the substituent, with formation of an intramolecular, six-membered ring. The process is analogous to condensed-phase cyclizations described for the same type of compounds. The fragmentation requires the presence of a double bond in the substituent group attached to the pyrrolic ring. A rearrangement process involving anchimeric assistance by the phenyl group (analogous to an ortho effect) is proposed for the formation of these ions.
AB - The protonated molecules and radical cations of meso-tetraphenylporphyrins with β-pyrrolic substituents, when formed by fast atom bombardment (FAB) and subjected to high-energy collisions, give rise to unexpected fragment ions. The reaction involves hydrogen migration from the ortho position of the phenyl ring to the α atom of the substituent, with formation of an intramolecular, six-membered ring. The process is analogous to condensed-phase cyclizations described for the same type of compounds. The fragmentation requires the presence of a double bond in the substituent group attached to the pyrrolic ring. A rearrangement process involving anchimeric assistance by the phenyl group (analogous to an ortho effect) is proposed for the formation of these ions.
UR - https://www.scopus.com/pages/publications/0036884530
U2 - 10.1016/S1044-0305(02)00705-5
DO - 10.1016/S1044-0305(02)00705-5
M3 - Article
C2 - 12484462
AN - SCOPUS:0036884530
SN - 1044-0305
VL - 13
SP - 1427
EP - 1431
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
IS - 12
ER -