Gas-phase study of molecular switches based on tautomeric proton transfer.

Abstract

The keto-enol tautomeric equilibrium in two newly developed molecular switches was studied by using various mass spectral techniques. In these two compounds, namely 4-(phenyldiazenyl)-2-(piperidin-1- ylmethyl)naphthalen-1-ol and 2-[(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)methyl]-4- (phenyldiazenyl)naphthalen-1-ol, the switching on/off states are achieved by a controlled shift of the tautomeric equilibrium. In the first compound, electron impact-mass spectrometry confirms that the unprotonated dye exists as an enol tautomer, while the electrospray ionization tandem mass spectrometry (ESI-MS/MS) experiment proves the clear shift to the keto tautomeric form under switching with acid addition. In the second compound, the addition of the alkali metal ions causes transition of the tautomeric equilibrium from the pure enol to the pure keto form. The ESI-MS study demonstrated better sensitivity towards lithium ions.

DOI: 10.1255/ejms.1106

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Cite this paper

@article{Nedeltcheva2011GasphaseSO, title={Gas-phase study of molecular switches based on tautomeric proton transfer.}, author={Daniela Nedeltcheva and Vanya B Kurteva and Liudmil Antonov}, journal={European journal of mass spectrometry}, year={2011}, volume={17 1}, pages={47-56} }