Fragmentation of pentacoordinate spirobicyclic aminoacyl-phosphoranes (P-AAs) by electrospray ionization tandem mass spectrometry concerning P–O and P–N bond cleavage
Article first published online: 26 SEP 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 25, Issue 20, pages 3151–3160, 30 October 2011
How to Cite
Hu, X., Gao, X., Zhu, J., Zeng, Z., Zhang, X., Lin, Z., Xu, P., Liu, Y. and Zhao, Y. (2011), Fragmentation of pentacoordinate spirobicyclic aminoacyl-phosphoranes (P-AAs) by electrospray ionization tandem mass spectrometry concerning P–O and P–N bond cleavage. Rapid Commun. Mass Spectrom., 25: 3151–3160. doi: 10.1002/rcm.5210
- Issue published online: 13 SEP 2011
- Article first published online: 26 SEP 2011
- Manuscript Accepted: 3 AUG 2011
- Manuscript Revised: 29 JUN 2011
- Manuscript Received: 16 APR 2011
The fragmentation pathways of both protonated and sodiated pentacoordinate spirobicyclic aminoacylphosphoranes (P-AAs) have been studied by electrospray ionization multi-stage mass spectrometry (ESI-MSn) in positive mode. The possible pathways and their mechanisms are elucidated through the combination of ESI-MS/MS, isotope (15 N and 2H) labeling and high-resolution Fourier transform ion cyclotron resonance (FTICR)-MS/MS. The relative Gibbs free energies (ΔG) of the product ions and possible fragmentation pathways are estimated at the B3LYP/6-31 G(d) level of theory. The theoretical calculations show that both protonated and sodiated P-AAs would quickly fragment before Berry pseudorotation. For protonated P-AAs, they have different tendencies to P–O or P–N bond cleavage. For sodiated P-AAs, the P–N bond is easier to cleave and produces the tetracoordinated phosphorus ion H. These results to some extent may give a clue to the chemistry of the active sites of phosphoryl transfer enzymes and will enrich the gas-phase ESI-MS ion chemistry of pentacoordinate phosphoranes. Copyright © 2011 John Wiley & Sons, Ltd.