Publications by authors named "Davi A C Ferreira"

Context: In this work, we did a theoretical exploration of CF (Ib) and its anion radical analogue (IIb) in this work. By investigating the thermochemistry of electron capture, we find that the free energy associated with the conversion of CH (Ia) into its anion radical analogue IIa is of the order of + 92.83 kcal.

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We describe the synthesis of two tetrachloroindate ionic liquids used as probes to study the involvement of NHCs (N-heterocyclic carbenes) in the distillation of imidazolium derivatives. Atmospheric-pressure chemical ionization mass spectrometry (APCI-MS), electrospray ionization mass spectrometry (ESI-MS), atmospheric-pressure thermal desorption ion mass spectrometry (APTDI-MS) and laser-induced acoustic desorption (LIAD) were used to depict the possibility of the involvement of NHCs during the distillation process. Each type of imidazolium derivative showed a particular mechanism of distillation, pointing firmly to the dependence of both the cation and the anion natures to distil as ion pairs or NHCs.

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Recent studies have reported surprising results related to the rearrangement of carbenes under ultracold conditions, making use of sophisticated models of quantum tunnelling to explain the observed phenomena. Here, we demonstrate that a methylhydroxycarbene (H3C-C-OH) rearrangement is possible by making changes in molecularity (i.e.

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The mechanism of the Ugi four-component reaction has been investigated by electrospray ionization (tandem) mass spectrometry using charge-tagged reagents (a carboxylic acid or an amine) to favour detection. Key intermediates were transferred directly via ESI(+) from the reaction solution to the gas phase and characterized by MS measurements and MS/MS collision induced dissociation. The Mumm rearrangement (final step) was also investigated by both travelling wave ion mobility mass spectrometry and DFT calculations.

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