Abstract
THE alkylation of aromatic hydrocarbons catalysed by aluminium chloride and similar Friedel-Crafts catalysts is ordinarily accompanied by the formation of deeply coloured oily liquids of high density. The structure of these ‘Friedel-Crafts complexes’ has been investigated by a number of workers1. H. C. Brown and H. W. Pearsal2 have proved the formation of a molecular complex from toluene and aluminium chloride – hydrogen chloride at low temperature. In further work, H. C. Brown and J. D. Brady3 have established the structure of the hydrogen chloride – aluminium chloride complexes of the methylbenzenes as σ-complexes in contrast to the proposed hydrogen chloride complexes which have a π-complex structure (after the representation of Dewar4). The formation of the onium or σ-complexes was proved by Brown by the hydrogen chloride technique by measuring the solubility of hydrogen chloride in the presence of aluminium chloride in the isomeric methylbenzenes.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
A summary of earlier work is contained in Thomas, C. A., “Anhydrous Aluminium Chloride in Organic Chemistry”, Amer. Chem. Soc. Mon. No. 87, pp. 48–54 (Reinhold Pub. Corp., New York, N.Y., 1941)
Brown, H. C., and Pearsal, H. W., J. Amer. Chem. Soc., 74, 191 (1952).
Brown, H. C., and Brady, J. D., J. Amer. Chem. Soc., 74, 3570 (1952).
Dewar, M. J. S., J. Chem. Soc., 406 (1946).
Norris, J. F., and Ingraham, N. J., J. Amer. Chem. Soc., 62, 1298 (1940).
Norris, J. F., and Wood, J. E., J. Amer. Chem. Soc., 62, 1428 (1940).
Brown, H. C., and Wallace, W. J., J. Amer. Chem. Soc., 75, 6268 (1953).
McCaulay, D. A., Shoemaker, B. H., and Lien, A. P., Indust. Eng. Chem., 42, 2103 (1950). See also McCaulay, D. A., and Lien, A. P., J. Amer. Chem. Soc., 73, 2013 (1951); 74, 6246 (1952).
Klatt, W., Z. anorg. allg. Chem., 234, 189 (1937).
Oláh, G., and Kuhn, S., Z. anorg. allgem. Chem. (in the press).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
OLÁH, G., KUHN, S. & PAVLÁTH, A. Isolation of the Stable Boron Trifluoride – Hydrogen Fluoride Complexes of the Methyl-benzenes ; the Onium Salt (or σ-Complex) Structure of the Friedel-Crafts Complexes. Nature 178, 693–694 (1956). https://doi.org/10.1038/178693b0
Issue Date:
DOI: https://doi.org/10.1038/178693b0
This article is cited by
-
Proton Migration in Benzene Complexes of Methyl and Silyl Cations
Russian Journal of General Chemistry (2005)
-
The Benzotrifluoride–Nitryl Fluoride–Boron Trifluoride Complex
Nature (1957)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.