The radical anions of 4-methyl-1-thiocoumarins and 4-methyl-1-thio-2-thionocoumarins are generated by internal electroreduction and studied by EPR spectrosopy. The spin density distribution is evaluated from the proton hfs coupling constants and by MO calculations. The radical anions of the corresponding coumarins and 2-thionocoumarins are not persistent enough for EPR spectroscopic measurements.
Part 16. BehrensT., BrunsS., and VossJ., J. Phys. Org. Chem., 2000, 13, 624.
2.
RöskeR., and VossJ., Phosphorus Sulfur, 1986, 26, 257.
3.
(a) SchmüserW., Ungesättigte Carbonyl-und Thiocarbonylverbindungen.—ESR-spektroskopische Untersuchungen ihrer Radikalanionen, PhD thesis, University of Hamburg, 1979; (b) R. Spohnholz, Stereoselektive Darstellung vinyloger Benzolcarbonsäureester und Untersuchungen zur Elektronenübertragung, PhD thesis, University of Hamburg, 1990.
4.
KlemmL.H., and OlsonR.D., J. Org. Chem., 1973, 38, 3390.
5.
GüntherH., and VossJ., J. Chem. Res., 1987 (S) 68; (M) 775.
6.
VossJ., and BruhnF.-R., Liebigs Ann. Chem., 1979, 1938.
7.
(a) VossJ., and SchlapkohlK., Tetrahedron, 1975, 31, 2982; (b) U. Debacher, W. Schmüser and J. Voss, J. Chem. Res., 1982 (S) 74; (M) 876; (c) L. Prangova, T. Strelow and J. Voss, J. Chem. Res., 1985 (S) 118; (M) 1401; (d) L.S. Prangova, A. Böge, B. Wollny and J. Voss, J. Chem. Res., 1987 (S) 182; (M) 1601; (e) L. Prangova, K. Osternack and J. Voss, J. Chem. Res., 1995 (S) 234; (M) 1551.
BüchelI., and VossJ., unpublished results, Univ. Hamburg, 1982; F. Schneider and M. Plato, Elektronenspinresonanz, Thiemig, München, 1972, p. 182f.
10.
GoldbergI.B., and PeakeB.M., J. Phys. Chem., 1977, 81, 571.
11.
CanningsR., Simple Huckel Molecular Orbital, SHMO, an iterative online program (http://www.chem.ucalgary.ca/SHMO/), based on: A. Rauk, Orbital Interaction Theory of Organic Chemistry, chapters 3 and 5, Wiley Interscience, Chichester, 1994.
12.
(a) GersonF., Hochauflösende ESR-Spektroskopie, Verlag Chemie, Weinheim, 1967; (b) F. Gerson and W. Huber, Electron Spin Resonance Spectroscopy of Organic Radicals, Wiley-VCH, Weinheim, 2003.
13.
ElsonI.H., and KempT.J., J. Chem. Soc., Faraday Trans. 2, 1973, 1402.
14.
(a) McConnellH.M., and RobertsonR.E., J. Phys. Chem., 1957, 61, 1018; (b) H.C. Heller, J. Am. Chem. Soc., 1967, 89, 4288.
15.
VossJ., SchmüserW., and SchlapkohlK., J. Chem. Res., 1977 (S) 144; (M) 1801.
16.
VossJ., EdlerR., and AdiwidjajaG., Phosphorus, Sulfur, Silicon, 2007, 182, in press.
(a) ItoK., and NakajimaK., J. Heterocycl. Chem., 1988, 25, 511; (b) A.C. Williams and N. Camp, Science of Synthesis, ed. ThomasR.J., Thieme Verlag, Stuttgart, 2003, Vol. 14, p.443.
