54128-17-5Relevant articles and documents
Acidity, basicity, and the stability of hydrogen bonds: Complexes of RO- + HCF3
Chabinyc, Michael L.,Brauman, John I.
, p. 10863 - 10870 (2007/10/03)
Ion-molecule complexes of RO- (R = Me, Et, i-Pr) and HCF3 have been studied with Fourier transform ion cyclotron resonance spectrometry. The RO- complexation energies with HCF3 were measured relative to RO-·H2O. These complexes, [ROHCF3]-, have complexation energies on the order of -20 kcal/tool and have low deuterium fractionation factors and are, therefore, hydrogen bonded. The structure of the complexes was studied by isotopic equilibrium experiments and ab initio calculations. All of the complexes studied have the structure RO-·HCF3 even when HCF3 is a stronger acid than ROH. The structure of the complexes can be understood through electrostatic arguments rather than the difference in acidity between the ion and neutral.
Electron transfer as a possible initial step in nucleophilic addition elimination reactions between (radical) anions and carbonyl compounds in the gas phase
Staneke, Paul O.,Ingemann, Steen,Nibbering, Nico M. M.
, p. 179 - 184 (2007/10/03)
The reactions of the HO-, CH3S-, CH2S- and CH2=C(CH3)-CH2- ions with three ketones (CF3COR; R=CH3, CF3, C6H5) and three esters of trifluoroacetic acid (CF3CO2R; R=CH3, C2H5 and C6H5) have been studied with use of Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry. All four negative ions react exclusively by proton transfer with CF3COCH3. With the other substrates, the HO- ion reacts by various pathways, such as proton transfer, SN2 substitution, E2 elimination and attack on the carbonyl group. The CH3S- ion is unreactive towards CF3COC6H5 but is able to react by hydride transfer, SN2, E2 and/or carbonyl attack with the remaining neutral species. The CH2S- radical anion reacts by electron transfer to afford stable molecular radical anions of CF3COCF3 and CF3COC6H5, whereas the main reaction with the two esters, CF3CO2CH3 and CF3CO2C2H5, is dissociative electron transfer leading to CF3CO2- and CF3- ions. The CH2=C(CH3)-CH2- anion displays a more complex reactivity pattern involving electron transfer, SN2, E2 as well as attack on the carbonyl group. Direct evidence for the occurrence of electron transfer as the initial step in an overall BAC2 type process has not been obtained for the systems studied. The reaction of the CH2S- ion with CF3CO2C6H5 was observed, however, to yield exclusively a CF3COCHS-. radical anion. Based upon the absence of a BAC2 process in the reaction of CH2S- with the methyl and ethyl esters of trifluoroacetic acid in combination with the facile occurrence of electron transfer from this radical anion, it is suggested that the CF3COCHS-. ion is formed by an initial electron transfer followed by coupling between the CH2S molecule and the CF3CO2C6H5- radical anion and subsequent loss of C6H5OH from the collision complex.
Product Branching in Infrared Multiple Photon Decomposition of Gas-Phase Ions. Mechanistic Implications for Proton-Transfer Reactions
Moylan, Christopher R.,Jasinski, Joseph M.,Brauman, John I.
, p. 1934 - 1940 (2007/10/02)
Negative ions that lie on potential surfaces for proton-transfer reactions have been photolyzed in the gas phase with an infrared laser.The relative photodissociation yields of reactants and products of the proton-transfer reactions as well as the kinetics of the reactions themselves have been measured.The results provide details about the potential surfaces, mechanisms. and theoretical theromochemistry of these reactions.
