Details

Autor(en) / Beteiligte

• van der Rest, G.
• Jensen, L.B.
• Azeim, S.Abdel
• Mourgues, P.
• Audier, H.E.

Titel

Reactions of [NH 3+·, H 2O] with carbonyl compounds: a McLafferty rearrangement within a complex?

Ist Teil von

• Journal of the American Society for Mass Spectrometry, 2004-07, Vol.15 (7), p.966-971

Ort / Verlag

New York, NY: Elsevier Inc

Erscheinungsjahr

2004

Link zum Volltext

Quelle

SpringerLink (Online service)

Beschreibungen/Notizen

• The reactions of the water solvated ammonia radical cation [NH 3 ·+, H 2O] with a variety of aldehydes and ketones were investigated. The reactions observed differ from those of low energy aldehydes and ketones radical cations, although electron transfer from the keto compound to ionized ammonia is thermodynamically allowed within the terbody complexes initially formed. The main process yields an ammonia solvated enol with loss of water and an alkene. This process corresponds formally to a McLafferty fragmentation within a complex. With aldehydes, another reaction can take place, namely the transfer of the hydrogen from the CHO group to ammonia, leading to the proton bound dimer of ammonia and water, and to the NH 4 + cation. Comparison between the available experimental results leads to the conclusion that the McLafferty fragmentation occurs within the terbody complex initially formed, with no prior ligand exchange, the water molecule acting as a spectator partner.