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A Correlation between Reactivity towards Free Radicals and Free Valence Number in Polycyclic Aromatics

Naturevolume 169pages153154 (1952) | Download Citation



IN recent papers dealing with theoretical molecular properties derivable on the basis of quantum mechanics, Coulson and others1,2 stated that the free valence number calculated for a given carbon atom should be related to its ability to interact with a free radical, being a measure for the unused bonding power of that atom.

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  1. 1

    Coulson, C. A., J. Chim. Phys., 45, 243 (1948). Burkitt, F. H., Coulson, C. A., and Longuet-Higgins, H. C., Trans. Farad. Soc., 47, 553 (1951).

  2. 2

    Daudel, R., et al., Bull. Soc. chim. France, 17, 66 (1950).

  3. 3

    Kooyman, E. C., Rec. Tr. Chim. Pays Bas, 69, 492 (1950). Kooyman, E. C., and Farenhorst, E., ibid., 70, 867 (1951). Cf. Kharasch, M. S., et al., J. Amer. Chem. Soc., 69, 1100, 1105 (1947).

  4. 4

    Kooyman, E. C., Disc. Farad. Soc. on Hydrocarbons, April 1951 (in the press).

  5. 5

    Kharasch, M. S., and Sage, M., J. Org. Chem., 14, 537 (1949).

  6. 6

    These were taken from: (a) Berthier, G., et al., C.R. Acad. Sci. Paris, 226, 1906 (1948). (b) Baldock, G., et al., C.R. Acad. Sci. Paris, 228, 931 (1949). (c) Vroelant, C., and Daudel, R., Bull Soc. chim. France, 16, 217 (1949).

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  1. Koninklijke/Shell-Laboratorium, Amsterdam

    • E. C. KOOYMAN
    •  & E. FARENHORST


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