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Characteristic frequencies in the infrared spectra of pyrazolines

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Chemistry of Heterocyclic Compounds Aims and scope

Abstract

Pyrazolines are characterized by valence vibrations at the following frequencies: C=N (1580–1627 cm−1), H-C3=N (3040–3063 cm−1), H-N (3270–3305 cm−1) and CH3-N (2780–2805 cm−1). Lowering of the frequencies of the valence vibrations of C=N in pyrazolines, when compared with the magnitudes characteristic of alkyledene amines and oximes, is regarded as a consequence of coupling with the unshared electron pair of the neighboring nitrogen atom. By means of the IR spectra, it is possible to determine the position of the double bonds in the pyrazoline ring, to distinguish between pyrazolines substituted and nonsubstituted in positions 1 and 3, and to establish the presence of geminate (twin) methyl groups and methyl groups in position 1.

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References

  1. B. V. Ioffe and K. N. Zelenin, ZhOKh, 33, 3589, 1963.

    Google Scholar 

  2. R. H. Wiley, C. H. Jarboe, F. N. Hayes, E. Hansbury, J. T. Nielsen, P. X. Callahan, and M. C. Sellars, J. Org. Chem., 23, 732, 1958.

    Google Scholar 

  3. L. Bellamy, Infrared Spectra of Complex Molecules [Russian translation], IL, Moscow, 1963.

    Google Scholar 

  4. B. V. Ioffe and D. D. Tsitovich, ZhOKh, 33, 3449, 1963; DAN, 155, 1348, 1964.

    Google Scholar 

  5. B. V. Ioffe and D. D. Tsitovich, KhGS [Chemistry of Heterocyclic Compouns], 559, 1965.

  6. B. V. Ioffe, Z. I. Sergeeva, V. V. Tsibul'skii, and N. I. Klyueva, ZhOrKh, 3, 988, 1967.

    Google Scholar 

  7. B. V. Ioffe, V. S. Stopskii, and Z. I. Sergeeva, ZhOrKh, 3, 1171, 1967.

    Google Scholar 

  8. B. V. Ioffe, V. V. Tsibul'skii, V. S. Stopskii, and Z. I. Sergeeva, KhGS [Chemistry of Heterocyclic Compounds], 6, 1966.

  9. R. H. Wiley, S. C. Slaymaker, and H. Kraus, J. Org. Chem., 22, 204, 1957.

    Google Scholar 

  10. B. V. Ioffe, O. V. Sverdlova, and L. M. Korzhikova, Zhur. teoret. i eksp. khim., 3, 1, 1967.

    Google Scholar 

  11. A. J. Meyers, J. Org. Chem., 26, 218, 1961.

    Google Scholar 

  12. A. J. Meyers, J. Org. Chem., 24, 1233, 1959.

    Google Scholar 

  13. R. J. Crawford, R. J. Dummel, and A. Mishra, J. Am. Chem. Soc., 87, 3023, 1965.

    Google Scholar 

  14. C. D. Overberger and J. P. Anselme, J. Am. Chem. Soc., 86, 658, 1964.

    Google Scholar 

  15. R. J. Crawford, A. Mishra, and R. J. Dummel, J. Am. Chem., Soc., 88, 3959, 1966.

    Google Scholar 

  16. L. Spialter, D. H. O'Brien, G. L. Untereiner, and W. A. Rush, J. Org. Chem., 30, 3278, 1965.

    Google Scholar 

  17. J. T. Braunholtz, E. A. V. Ebsworth, F. G. Mann, and N. Sheppard, J. Chem. Soc., 2780, 1958.

  18. R. D. Hill and O. G. D. Meakins, J. Chem. Soc., 760, 1958.

  19. W. B. Wright, J. Org. Chem., 24, 1362, 1959.

    Google Scholar 

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Ioffe, B.V. Characteristic frequencies in the infrared spectra of pyrazolines. Chem Heterocycl Compd 4, 791–793 (1968). https://doi.org/10.1007/BF00486963

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