Gas-phase fragmentation of protonated C60-pyrimidine derivatives

✍ Scribed by Catarina I. V. Ramos; M. G. Santana-Marques; Roger F. Enes; Augusto C. Tomé; José A. S. Cavaleiro; Manuel Nogueras

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 324 KB
• Volume: 44
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1564

✦ Synopsis

Abstract

Electrospray ionization mass spectrometry/mass spectrometry (ESI/MS/MS) and multiple stage mass spectrometry (MS^n^, n > 2) were used in the positive ion mode, with two different types of mass spectrometers, a quadrupole time‐of‐flight and an ion trap, to characterize two sets of different types of C~60~‐aminopyrimidine exohedral derivatives. In one set, the pyrimidine moiety bears an amino acid methyl ester residue, and in the other the pyrimidine ring is part of a nucleoside‐type moiety, the latter existing as two separated diastereoisomers.

We have found that retro‐cycloaddition processes occur for the closed shell protonated species formed by electrospraying C~60~ derivatives synthesized by Diels–Alder reactions, whereas for the C~60~ derivatives synthesized via 1,3‐dipolar cycloadditions, these processes did not occur. Formation of diagnostic ions allowed the differentiation between the two groups of fullerene derivatives, and between the diastereoisomers of C~60~ derivatives with a nucleoside‐type moiety. In general, the fragmentation processes are strongly dependent on the protonation sites and on the structure of the exohedral moieties. Copyright © 2009 John Wiley & Sons, Ltd.