ABSTRACT
The fragmentations of argentinated N-allylbenzamides have been exhaustively studied through collision-induced dissociation and through deuterium labeling. The intriguing elimination of AgOH is certified as the consequence of intramolecular cyclization between terminal olefin and carbonyl carbon following proton transfer to carbonyl oxygen, rather than simple enolization of amide. Linear free energy correlations and density functional theory (DFT) calculations were performed to understand the competitive relationship between AgOH loss and AgH loss, which results from the 1,2-elimination of α-hydrogen (to the amido nitrogen) with the silver.
Subject(s)
Allyl Compounds/chemistry , Benzamides/chemistry , Models, Molecular , Organometallic Compounds/chemistry , Silver/chemistry , Catalysis , Energy Transfer , Hot Temperature , Hydroxides/analysis , Hydroxides/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Silver/analysis , Silver Compounds/analysis , Silver Compounds/chemistry , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry , VolatilizationABSTRACT
In collisional activation of argentinated N-arylmethyl-pyridin-2-ylmethanimine, a neutral molecule of AgNH2 is eliminated, carrying one hydrogen from the methylene and the other one from the ortho position (relative to the ipso carbon) of the aryl ring. Taking argentinated N-benzyl-pyridin-2-ylmethanimine for example, the proposition that the AgNH2 loss results from intramolecular arylmethyl transfer combined with cyclodeamination is rationalized by deuterium labeling experiments, blocking experiments, and theoretical calculations. The structure of the final product ion from loss of AgNH2 was confirmed further by multistage mass spectrometry.