Fulvio Cacace

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Fulvio Cacace (died 1 December 2003 [1] ) was an Italian chemist.

In 1963, while at the Sapienza University of Rome, he devised the decay technique for the study of organic radicals and carbenium cations. [2] [3] The technique is based on the preparation of compounds containing the radioactive isotope tritium in place of common hydrogen. When the tritium undergoes beta decay, it is turned into a helium-3 atom, that detaches from the parent molecule, leaving the desired cation or radical behind.

The technique has made it possible to study the chemistry of a vast number of such radicals and ions, in all sorts of environments, including solids, liquids, and gases. In particular, it has provided much of the knowledge of the chemistry of the helium hydride ion, specifically [3He3H]+. [4] [5] [3]

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Carbocation Ion with a positively charged carbon atom

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3, methanium CH+
5 and vinyl C
2H+
3 cations. Occasionally, carbocations that bear more than one positively charged carbon atom are also encountered.

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Directed ortho metalation Chemical reaction

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Cation–pi interaction

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Group 2 organometallic chemistry

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Helium hydride ion Chemical compound

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Birch reduction Organic reaction used to convert arenes to cyclohexadienes

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Marjorie Constance Caserio was an English chemist. In 1975, she was awarded the Garvan Medal by the American Chemical Society.

Ethenium

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2H+
5. It can be viewed as a molecule of ethylene with one added proton, or a molecule of ethane minus one hydride ion. It is a carbocation; more specifically, a nonclassical carbocation.

2,4,6-Tri-<i>tert</i>-butylphenol Chemical compound

2,4,6-Tri-tert-butylphenol (2,4,6-TTBP) is a phenol symmetrically substituted with three tert-butyl groups and thus strongly sterically hindered. 2,4,6-TTBP is a readily oxidizable aromatic compound and a weak acid. It oxidizes to give the deep-blue 2,4,6-tri-tert-butylphenoxy radical. 2,4,6-TTBP is related to 2,6-di-tert-butylphenol, which is widely used as an antioxidant in industrial applications. These compounds are colorless solids.

Cyclopropenium ion

The cyclopropenium ion is the cation with the formula C
3H+
3. It has attracted attention as the smallest example of an aromatic cation. Its salts have been isolated, and many derivatives have been characterized by X-ray crystallography. The cation and some simple derivatives have been identified in the atmosphere of the Saturnian moon Titan.

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References

  1. ↑ "Fulvio Cacace". Obituary notice, published 2003-12-03; website of the Italian daily La Repubblica. Accessed on 2019-04-23.
  2. ↑ Fulvio Cacace (1964): Proceedings of the 1963 Conference on the Methods for Preparing and Storing Marked Molecules, Bruxelles, page 179. Euratom report EUR.1625.e.
  3. 1 2 3 Fulvio Cacace (1970): "Gaseous Carbonium Ions from the Decay of Tritiated Molecules". Advances in Physical Organic Chemistry, volume 8, pages 79-149. doi : 10.1016/S0065-3160(08)60321-4
  4. ↑ Maurizio Speranza (1993): "Tritium for generation of carbocations". Chemical Reviews, volume 93, issue 8, pages 2933–2980. doi : 10.1021/cr00024a010.
  5. ↑ G. P. Akulov (1976): "Ion-molecular reactions initiated by β-decay of tritium in tritiated compounds" ("Ionn-molekulyarnye reaktsii, initsiirovannye β-raspadom tritiya v tritirovannykh soedineniyakh"). Uspekhi Khimii (USSR), volume 45, issue 2, pages 1970-1999. (No DOI).
  6. ↑ Fulvio Cacace, Giovanna Ciranni, and Angelo Guarino (1966): "A Tracer Study of the Reactions of Ionic Intermediates Formed by Nuclear Decay of Tritiated Molecules. I. Methane-t4". Journal of the American Chemical Society, volume 88, issue 13, pages 2903–2907. doi : 10.1021/ja00965a004
  7. ↑ Fulvio Cacace and Pierluigi Giacomello (1973): "Gas-phase reaction of tert-butyl ions with arenes. Remarkable selectivity of a gaseous, charged electrophile". Journal of the American Chemical Society, volume 95, issue 18, pages 5851–5856. doi : 10.1021/ja00799a002
  8. ↑ Pierluigi Giacomello and Fulvio Cacace (1976): "Gas-phase alkylation of xylenes by tert-butyl(1+) ions". Journal of the American Chemical Society, volume 98, issue 7, pages 1823–1828.doi : 10.1021/ja00423a029
  9. ↑ Marina Attina, Fulvio Cacace, Giovanna Ciranni, and Pierluigi Giacomello (1977): "Aromatic substitution in the gas phase. Ambident behavior of phenol toward t-C4H9+ cations". Journal of the American Chemical Society, volume 99, issue 15, pages 5022–5026. doi : 10.1021/ja00457a022.
  10. ↑ Fulvio Cacace and Pierluigi Giacomello (1977): "Aromatic substitution in the liquid phase by bona fide free methyl cations. Alkylation of benzene and toluene". Journal of the American Chemical Society, volume 99, issue 16, pages 5477–5478. doi : 10.1021/ja00458a040.
  11. ↑ Fulvio Cacace and Pierluigi Giacomello (1978): "Aromatic substitutions by [3H3]methyl decay ions. A comparative study of the gas- and liquid-phase attack on benzene and toluene". Journal of the Chemical Society, Perkin Transactions 2, issue 7, pages 652-658. doi : 10.1039/P29780000652
  12. ↑ Marina Attinà, Fulvio Cacace, Giovanna Ciranni, and Pierluigi Giacomello (1979): "Gas-phase reaction of free isopropyl ions with phenol and anisole". Journal of the Chemical Society, Perkin Transactions 2, issue 7, pages 891-895. doi : 10.1039/P29790000891
  13. ↑ Marina Attina, Fulvio Cacace, and Pierluigi Giacomello (1980): "Aromatic substitution in the gas phase. A comparative study of the alkylation of benzene and toluene with C3H7+ ions from the protonation of cyclopropane and propene". Journal of the American Chemical Society, volume 102, issue 14, pages 4768–4772. doi : 10.1021/ja00534a032
  14. ↑ Fulvio Cacace, Giovanna Ciranni, and Pierluigi Giacomello (1981): "Aromatic substitution in the gas phase. Alkylation of arenes by gaseous C4H9+ cations". Journal of the American Chemical Society, volume 103, issue 6, pages 1513–1516. doi : 10.1021/ja00396a035
  15. ↑ Fulvio Cacace (1982): "On the formation of adduct ions in gas-phase aromatic substitution". Journal of the Chemical Society, Perkin Transactions 2, issue 9, pages 1129-1132. doi : 10.1039/P29820001129.
  16. ↑ Fulvio Cacace, Giovanna Ciranni, and Pierluigi Giacomello (1982): "Alkylation of nitriles with gaseous carbenium ions. The Ritter reaction in the dilute gas state". Journal of the American Chemical Society, volume 104, issue 8, pages 2258–2261. doi : 10.1021/ja00372a025
  17. ↑ Fulvio Cacace, Giovanna Ciranni and Pierluigi Giacomello (1982): "Aromatic substitution in the gas phase. Alkylation of arenes by C4H9+ ions from the protonation of C4 alkenes and cycloalkanes with gaseous Brønsted acids". Journal of the Chemical Society, Perkin Transactions 2, issue 11, pages 1129-1132. doi : 10.1039/P29820001129
  18. ↑ Marina Attina, and Fulvio Cacace (): "Aromatic substitution in the gas phase. Intramolecular selectivity of the reaction of aniline with charged electrophiles". Journal of the American Chemical Society, volume 105, issue 5, pages 1122–1126. doi : 10.1021/ja00343a009
  19. ↑ H. Colosimo, M. Speranza, F. Cacace, G. Ciranni (1984): "Gas-phase reactions of free phenylium cations with C3H6 hydrocarbons", Tetrahedron, volume 40, issue 23, pages 4873-4883. doi : 10.1016/S0040-4020(01)91321-3
  20. ↑ Marina Attina, Fulvio Cacace, and Giulia De Petris (1085): "Intramolecular selectivity of the alkylation of substituted anilines by gaseous cations". Journal of the American Chemical Society, volume 107, issue 6, pages 1556–1561. doi : 10.1021/ja00292a017
  21. ↑ Fulvio Cacace, and Giovanna Ciranni (1986): "Temperature dependence of the substrate and positional selectivity of the aromatic substitution by gaseous tert-butyl cation". Journal of the American Chemical Society, volume 108, issue 5, pages 887–890. doi : 10.1021/ja00265a006
  22. ↑ Fulvio Cacace (1990): "Nuclear Decay Techniques in Ion Chemistry". Science, volume 250, issue 4979, pages 392-399. doi : 10.1126/science.250.4979.392.
  23. ↑ Fulvio Cacace, Maria Elisa Crestoni, and Simonetta Fornarini (1992): "Proton shifts in gaseous arenium ions and their role in the gas-phase aromatic substitution by free Me3C+ and Me3Si+ [tert-butyl and trimethylsilyl] cations". Journal of the American Chemical Society, volume 114, issu 17, pages 6776–6784. doi : 10.1021/ja00043a024
  24. ↑ Fulvio Cacace, Maria Elisa Crestoni, Simonetta Fornarini, and Dietmar Kuck (1993): "Interannular proton transfer in thermal arenium ions from the gas-phase alkylation of 1,2-diphenylethane". Journal of the American Chemical Society, volume 115, issue 3, pages 1024–1031. doi : 10.1021/ja00056a029


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