Reactions with Alkoxide Anions
Part of the Lecture Notes in Chemistry book series (LNC, volume 31)
The development of negative chemical ionization (NCI) as a technique in the field of analytical mass spectrometry has stimulated interest in detailed studies of processes involving negative ions such as O-·, OH-, alkoxide and halide anions . In a recent publication, we have demonstrated the potential use of the reactant ion 0-· to probe the structure of aliphatic alcohols ; it was found that the product distribution in these systems allows for analysis of structural isomers. On the other hand, reaction of OH- with alcohols resulted in formation of the alkoxide anion, thus allowing for the determination of molecular weights; only minor formation of the corresponding enolate anion was observed. It could be that the latter product ion might be formed via pyrolytic dehydrogenation of the alcohol molecule to the corresponding aldehyde or ketone that would in turn transfer a proton to a strong base such as OH to form the enolate anion. Preliminary results  indicated that under our conditions (very diluted alcohol.N2O or alcohol/H2O mixtures), pyrolysis plays a minor role and that the formation of enolate occurs in a collisionary induced loss of H2 from the alkoxide anion, reaction 1, in which M stands for a bath gas molecule.
KeywordsIonization Cross Section Negative Chemical Ionization Dissociative Electron Attachment Time Dependent Concentration Total Ionization Cross Section
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
Unable to display preview. Download preview PDF.
- 1.a) Environm. Health Perspect. 36 (1980),Google Scholar
- 1.b) K. R. Jennings in “Mass Spectrometry”, Vol. 4, ed. by R.A.W. Johnstone, The Chemical Society, London (1977),Google Scholar
- 2.G. Boand, R. Houriet and T. Gaumann, in “Advances in Mass Spectrometry”, Vol. 8, ed. by A. Quayle, Heyden, London (1980).Google Scholar
- 6.see for instance J.M.S. Hem’s, in “Ion Molecule Reactions”, ed by J.L. Franklin, Vol. 2, Butterworths, London (1972).Google Scholar
- 7.Values for ionization cross sections taken from: “Mass Spectrometry”, C.A. McDowell, ed. McGrawHill, New York (1963)Google Scholar
- 7a.estimated by the method outlined by J.E. Bartmess, R. Georgiadis and G.W. Caldwell, 28th Ann. Conf. on Mass Spectrom., paper MAMP20, New York City (1980).Google Scholar
- 8.Organic Syntheses, Coll. Vol. II (1969) 108.Google Scholar
- 9.A.J. Noest and N.M.M. Nibbering, in ref. 2, p. 227Google Scholar
© Springer-Verlag Berlin Heidelberg 1982