426
MARZIANO ET AL.
SO3, H2S2O7) do not allow univocal explanations
of the mechanistic path of the solvent. Nevertheless,
in the range where [H2SO4] molecular species are
available, solute–solvent interactions by the OH
groups and a proton-jump conduction mechanism
would be expected to be reasonably effective.
3. Ogata, Y.; Okano, M.; Matsumoto, K. J Am Chem Soc
1955, 77, 4643.
4
5
6
7
8
. Greer, F.; Pearson, D. E. J Am Chem Soc 1955, 77,
649.
. McNulty, P. J.; Pearson, D. E. J Am Chem Soc 1959, 81,
12.
. Vinnik, M. I.; Zarakhani, N. G. Russ Chem Rev (Eng.
Trans.) 1967, 36, 51.
6
6
c. New and old [7,24] spectroscopic measurements
show that the nitrilium ion is an intermediate of
the reaction whose stability as “long-lived free
species” is determined from the structure of the
starting oxime and from the solute–solvent inter-
actions. For instance, the high slopes observed
for the destruction of the intermediate of TMTOX
in perchloric, triflic, and sulfuric acids suggest
that interactions between ionic species [27] giving
. Gregory, B. J.; Moodie, R. B.; Schofield, K. J Chem Soc
(B) 1970, 338.
. Kim, S. G.; Kawakami, T.; Ando, T.; Yukawa, Y. Bull
Chem Soc Japan 1979, 52, 1115.
9. Sampoli, M.; Marziano, N. C.; Tortato, C. J Phys Chem
1989, 93, 7252.
0. Marziano, N. C.; Tortato, C.; Bertani, R. J Chem Soc,
Perkin Trans 2 1992, 955.
11. Marziano, N. C.; Tomasin, A.; Tortato, C. Org React
(Estonia) 1996, 30, 29.
1
+
−
−
ion pairs {i.e. [Me C N C6H3Me3] X , (X =
−
−
−
ClO4 , CF3SO3 , HSO4 )} are occurring, whose
stability increases with increase in the acid con-
centration. Analogously, the ion pairs formed be-
tween the starting oxime and the solvent (i.e.
1
1
1
2. Marziano, N. C.; Tomasin, A.; Tortato, C. Org React
Estonia) 1996, 30, 39.
(
3. Marziano, N. C.; Tomasin, A.; Tortato, C.; Isandelli, P.
J Chem Soc, Perkin Trans 2 1998, 2535.
4. Marziano, N. C.;Tomasin, A.;Tortato, C.;Zaldivar, J. M.
J Chem Soc, Perkin Trans 2 1998, 1973.
15. Marziano, N. C.; Tortato, C.; Ronchin, L.; Bianchi, C.
Catal Lett 1998, 56, 159.
6. Marziano, N. C.; Tortato, C.; Ronchin, L.; Bianchi, C.
Catal Lett 2000, 64, 15.
❍
+
−
[
✟C NH OH] CF3SO3 ) could decrease the re-
action rates observed in CF3SO3H above 90 wt%
−
+
(
see Fig. 1), where [CF3SO3 H3O ] species have
also been detected [9]. As a matter of fact two
acids with different acid strength as CF3SO3H and
CH3SO3H appear to be equally effective on the com-
parison of reaction rates at high acid concentrations
1
1
7. Marziano, N. C.; Ronchin, L.; Tortato, C.; Zingales, A.;
Sheikh-Osman, A. A. J Mol Catal A: Chemical 2001,
(see Table I).
174, 265.
1
1
2
8. Bax, A.; Subramian, S. J Magn Reson 1986, 67, 565.
9. Otting, G.; W u¨ trich, K. J Magn Reson 1988, 76, 569.
0. Drobny, G.; Pines, A.; Sinton, S.; Weitekamp, D.;
Wemmer, D. Faraday Symp Chem Soc 1979, B33, 49.
The new results are consistent with the view that
the catalytic trend of sulfuric acid and the interactions
between the ionic species are very important experi-
mental observations to be taken into account when an
extension of the Beckmann rearrangement over solid
acid catalysts is attempted.
21. Marziano, N. C.; Tortato, C.; Sampoli, M. J Chem Soc,
Perkin Trans 2 1991, 423.
22. Marziano, N. C.; Tortato, C.; Ronchin, L.; Martini, F.;
Bianchi, C. Catal Lett 1999, 58, 81.
2
2
3. Turrell, G. C.; Gordon, J. E. J Chem Phys 1959, 30, 895.
4. Olah, G. A.; Kiovsky, T. E. J Am Chem Soc 1968, 90,
BIBLIOGRAPHY
4666.
2
5. Lalinowski, H.O.; Berger, S.; Braun, S. Carbon-13 NMR
Spectroscopy; Wiley: Chichester, 1988.
1. March, J. Advanced Organic Chemistry: Reaction,
Mechanisms and Structure, 3rd ed.; Wiley: New York,
26. Nguyen, M. T.; Raspoet, G.; Vanquickenborne, L. G. J
Chem Soc, Perkin Trans 1997, 2, 821.
1
985; p. 987.
2
. Liler, M. Reaction Mechanisms in Sulphuric Acid; Aca-
demic Press: London, 1971.
27. Reichardt, C. Solvent Effects in Organic Chemistry, Ver-
lag Chemie: New York, 1979.