18860-15-6Relevant articles and documents
Bridging the Gap between the Gas Phase and Solution: Transition in the Kinetics of Acid-Base Reactions
Bohme, Diethard K.,Rakshit, Asit B.,Mackay, Gervase I.
, p. 1100 - 1101 (1982)
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Reactions of Hydrated Hydronium Ions and Hydrated Hydroxide Ions with Some Hydrocarbons and Oxygen-Bearing Organic Molecules
Spanel, Patrik,Smith, David
, p. 15551 - 15556 (1995)
The rate coefficients and ion products have been determined at 300 K for the reactions of H3O(1+)*(H2O)0,1,2,3 positive ions and OH(1-)*(H2O)0,1,2 negative ions with six hydrocarbons and six oxygen-containing organic species using a selected ion flow tube (SIFT) for the positive ions and a flowing afterglow (FA) for the negative ions.This study was initiated in support of a major development program of the SIFT and FA as chemical ionization devices for the analysis of trace gases in air and especially of human breath and the vapors emitted by fruits and food products.The H3O(1+) and OH(1-) ions mostly react with the molecules, MH, via proton transfer, producing respectively MH2(1+) and M(1-) ions, which is ideal for gas analysis.The hydrated hydronium ions and the hydrated hydroxide ions are largely unreactive with the hydrocarbons included in this study, but they are very reactive with the oxygen-containing organic molecules undergoing ligand switching reactions producing mostly MH2(1+) and M(1-) hydrates.The details of the reactions (e.g. the number of H2O molecules either ejected from the intermediate complexes or remaining associated with the MH2(1+) and MH(1-) "core ions") are controlled largely by the reaction energy as far as this can be determined.The utility of the reactions of these hydrated ions as chemical ionization agents in atmospheric trace gas analysis is alluded to.Additionally, new FA data on the three-body association reactions of OH(1-) and OH(1-)*H2O with CO2 are presented.
Gas-phase ionic reactions of benzyl and methoxide anions
Gatev, Geo G.,Zhong, Meili,Brauman, John I.
, p. 531 - 536 (2007/10/03)
Gas-phase reactions of benzyl and methoxide anions with alkyl formate and other esters were compared using Fourier transform io cyclotron resonance spectroscopy. Although these anions have similar basicities, in many cases the reaction pathways differ.
Trimethylphosphine: Anion-Molecule Reactions and Acidity in the Gas Phase
Grabowski, Joseph J.,Roy, Paul D.,Leone, Robert
, p. 1627 - 1632 (2007/10/02)
Gas-phase acidity of trimethylphosphine has been investigated at ambient temperature by examining proton-transfer reactions in 40 Pa of helium buffer gas in a Flowing Afterglow instrument.On the basis of the occurence-non-occurence of a number of proton-transfer reactions and the observation of rapid H-D exchange between D2O and the conjugate base of trimethylphosphine, it has been determined that trimethylphosphine is more acidic than water.Quantitative measurements are reported for the reaction of trimethylphosphine with atomic oxygen anion and methoxide.These latter two anions exhibit multiple reaction pathways, one of which is proton transfer.From measurements of the rate coefficients of these two reactions and the relative product yields, it is concluded that the gas-phase acidity of trimethylphosphine is very similar to that of the hydroxyl radical; the recommended value is ΔGoacid(PMe3) 1577 +/- 13kJ mol-1.The derived acidity measurement is in slight contrast to recent theoretical and experimental estimates.Furthermore, it is found that anions which react only slowly with trimethylphosphine by proton transfer can undergo an alternative reaction which corresponds to addition of the neucleophilic anion to trimethylphosphine followed by loss of methane.
