Abstract
In situ NMR spectroscopy can be applied to investigate chemical reactions during which free radicals occur as intermediates. In chemical systems of low molecular weight, nuclear spin polarization results from the spin selectivity of free radical reactions because a pair of radicals, like any other given set of particles, has to obey the exclusion principle. Therefore, this system reacts selectively in terms of the participating nuclear spins when forming a chemical single bond. As a consequence, strong transient absorption and emission lines occur in NMR spectra acquired during a reaction of free radicals. This extraordinary phenomenon has become known as chemically induced dynamic nuclear polarization (CIDNP). Ever since its experimental discovery and theoretical verification, CIDNP has been employed to study the mechanisms of free radical reactions in solution. As such it has proven to be a very valuable tool for the elucidation of the mechanism of these reactions and, more importantly, to discriminate reaction pathways that include the formation of transient radical species from those that exclusively follow a “diamagnetic” route, i.e., a pathway where no paramagnetic intermediates are formed whatsoever. More recently, the photo-CIDNP technique has also been employed extensively to probe the surface-accessibility of aromatic amino acid side-chains bound within a protein. As such, it can be used to study the dynamic features of a protein during folding, refolding, and also in the equilibrium or “steady state”, yielding both qualitative and quantitative information.
This review outlines the historical development of the CIDNP technique as well as its theoretical background. This is followed by a series of examples showing how CIDNP can be used to elucidate reaction pathways of chemical transformations comprising diamagnetic intermediates. Additionally, we present examples of how “biological” CIDNP experiments are usually performed and we show what kind of information can be extracted from these studies.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
Bargon J, Fischer H, Johnsen U (1967) Z Naturforschg A 20:1551
Bargon J, Fischer H (1967) Z Naturforschg A 20:1556
Ward HR, Lawler RG (1967) J Am Chem Soc 89:5518
Kaptein R, Dijkstra K, Nicolay K (1978) Nature 274:293
Hore PJ, Broadhurst RW (1993) Prog Nucl Magn Reson Spectrosc 25:345
Mok KH, Hore PJ (2004) Methods 34:75
Kuprov I, Hore PJ (2004) J Magn Reson 171:171
Fessenden RW, Schuler RH (1963) J Chem Phys 39:2147
Eichwald C, Walleczek J (1997) J Chem Phys 107:4943
Ritz T, Adem S, Schulten K (2000) Biophys J 78:707
Ritz T, Dommer DH, Phillips JB (2002) Neuron 34:503
Ritz T, Thalau P, Phillips JB, Wiltschko R, Wiltschko W (2004) Nature 429:177
Closs GL (1969) J Am Chem Soc 91:4552
Closs GL, Trifunac AD (1969) J Am Chem Soc 91:4554
Closs GL, Trifunac AD (1970) J Am Chem Soc 92:2183
Closs GL, Trifunac AD (1970) J Am Chem Soc 92:2186
Closs GL, Doubleday CE, Paulson DR (1970) J Am Chem Soc 92:2185
Kaptein R, Oosterhoff CJ (1969) Chem Phys Lett 4:195
Kaptein R, Oosterhoff CJ (1969) Chem Phys Lett 4:214
Adrian FJ (1970) J Chem Phys 53:3374
Adrian FJ (1971) J Chem Phys 54:3912
Noyes RM (1954) J Chem Phys 22:1349
Closs GL, Czeropski MS (1977) J Am Chem Soc 99:6127
Bargon J (1977) J Am Chem Soc 99:8350
Kaptein R (1971) Chem Comm, p 732
Kaptein R (1972) J Am Chem Soc 94:6251
Bargon J (2006) Photochem Photobiol Sci 5:970
Roth HD, Kaplan ML (1973) J Am Chem Soc 95:262
Bargon J (1971) J Am Chem Soc 93:4630
Sinclair J, Kivelson D (1968) J Am Chem Soc 90:5074
McConnell HM (1956) J Chem Phys 24:764
Maki AH, Geske DH (1961) J Am Chem Soc 83:1852
Oldham PH, Williams GH (1970) Chem Comm, p 1260
Kaptein R, Freeman R, Hill HDW, Bargon J (1973) Chem Comm, p 953
Pople JA, Beveridge DL, Dobosh PA (1968) J Am Chem Soc 90:4201
Freeman R, Hill HDW, Kaptein R (1972) J Magn Reson 7:82
Maurer HM, Gardini GP, Bargon J (1979) Chem Comm, p 272
Maurer HM, Bargon J (1979) J Am Chem Soc 101:6865
Maurer HM, Bargon J (1980) Org Mag Res 13:430
Mok KH, Nagashima T, Day IJ, Hore PJ, Dobson CM (2005) Proc Natl Acad Sci USA 102:8899
Closs GL, Czeropski MS (1977) Chem Phys Lett 45:115
Closs GL, Czeropski MS (1978) Chem Phys Lett 53:321
Kaptein R, Dijkstra K, Mueller F, Van Schagen CG, Visser AJWG (1978) J Magn Reson 31:171
Roth HD (1973) Mol Photochem 5:91
Roth HD, Manion ML (1975) J Am Chem Soc 97:6886
Kuprov I, Hore PJ (2004) J Magn Reson 168:1
Author information
Authors and Affiliations
Corresponding author
Editor information
Rights and permissions
Copyright information
© 2007 Springer-Verlag Berlin Heidelberg
About this chapter
Cite this chapter
Kuhn, L.T., Bargon, J. (2007). Exploiting Nuclear Spin Polarization to Investigate Free Radical Reactions via in situ NMR. In: Bargon, J., Kuhn, L.T. (eds) In situ NMR Methods in Catalysis. Topics in Current Chemistry, vol 276. Springer, Berlin, Heidelberg. https://doi.org/10.1007/128_2007_119
Download citation
DOI: https://doi.org/10.1007/128_2007_119
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-71426-2
Online ISBN: 978-3-540-71427-9
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)