The reactivity of ferrocenylalkyl azoles under the conditions of electrospray ionization

Single electron redox via an ion‐neutral complex in the fragmentation of protonated benzoylferrocenes

“…So, in the case of protonated benzoylferrocene, it is reasonable to proposed that within the [benzoyl/ferrocene] ion‐neutral complex intermediate, an electron is transferred from the neutral ferrocene to the benzoyl cation leading to the formation of the ferrocinium cation, where the divalent iron, Fe(II), is oxidized to the trivalent iron, Fe(III). Moreover, by the help of DFT calculations, Rodionov's group has found that under ESI conditions the initial ferrocene derivative molecules were oxidized by the protonated ones to form molecular ions . It is sound to propose that ferrocene‐containing substances are facile to participate in redox processes in the gas phase as they do in the solid and liquid phase .…”

“…Moreover, by the help of DFT calculations, Rodionov's group has found that under ESI conditions the initial ferrocene derivative molecules were oxidized by the protonated ones to form molecular ions. [10,11] It is sound to propose that ferrocene-containing substances are facile to participate in redox processes in the gas phase as they do in the solid and liquid phase. [5,24] A schematic potential energy surface of the model compound benzoylferrocene is given in Fig.…”

“…In the recent years, considerable experimental and theoretical calculation studies have demonstrated that ferrocene and some of its derivatives are easily oxidized during electrospray ionization (ESI) with the formation of molecular ions . However, the details of the fragmentation mechanisms of protonated benzoylferrocenes in collision‐induced dissociation (CID) mass spectrometry (MS) have not been obtained.…”

Mass Spectrometry in Russia

“…Using ferrocenylalkyl azoles and deuterium-labeled experiments, the same authors have discovered new mechanisms of ion production in ESI called ''activating protonation". 58,59 As has been shown earlier, these compounds under ESI conditions underwent oxidation, protonation, fragmentation and ferrocenylalkylation to form molecular ions [M] +• , protonated molecules [M + H] + , ferrocenylalkyl cations [FcCHR] + and bisferrocenylalkyl azole cations [(FcCHR) 2 X] + , respectively. 60,61 On the basis of special experimental techniques (deuterated solvents, saturation of the ionic source of an ESI mass spectrometer by the vapors of deuterated and unlabeled solvents, the experiments under ''inverse" ESI conditions when the solvent is subjected to electrospray in the presence of ferrocenylalkyl derivative vapors) and quantumchemical calculations, the scheme of the formation of these ions in a gas phase was suggested.…”

“…Analogies between the reactivity of compounds in conditions of EI, ESI and acid catalysis were established. 62 Note joint investigations performed at IOEC RAS and the Institute of Organic Chemistry (Ufa Research Center of RAS) on the application of negative ion mass spectrometry to organoelement compounds. One such work has been devoted to resonance capture of electrons to cyclopentadienyltricarbonylmanganese and -rhenium derivatives.…”