Utente:Grasso Luigi/sanbox1/Ozoniuro
| Ozoniuro | |
|---|---|
| Nome IUPAC | |
| Triossidan-1-id-3-ile [1] | |
| Caratteristiche generali | |
| Formula bruta o molecolare | O3 |
| Massa molecolare (u) | 47.999 |
| Numero CAS | |
| PubChem | 11966307 |
| SMILES | [O-]O[O] |
| Indicazioni di sicurezza | |
| Simboli di rischio chimico | |
 
| |
| attenzione | |
| Frasi H | --- |
| Consigli P | --- [3] |
Gli ozonuri sono composti chimici derivati dall'ozono.[4] In chimica inorganica con il termine "ozonuro" si indica l'anione instabile O3-, che tende a formare composti ionici di colore rosso scuro.[5]
Ozonide is the unstable, reactive polyatomic anion O−3 analog of ozone or any of several classes of organic organic peroxide compounds similar formed by the reaction of ozone with an unsaturated compound.
Ozoniuro ionico[modifica | modifica wikitesto]
Inorganic ozonides[6] are dark red ionic compounds containing the reactive O−3 anion. The anion has the bent shape of the ozone molecule.
Inorganic ozonides are formed by burning potassium, rubidium, or caesium in ozone, or by treating the alkali metal hydroxide with ozone; if potassium is left undisturbed in air for years it accumulates a covering of superoxide and ozonide. They are very sensitive explosives that have to be handled at low temperatures in an atmosphere consisting of an inert gas. Lithium and sodium ozonide are extremely unstable and must be prepared by low-temperature ion exchange starting from CsO3. Sodium ozonide, NaO3, which is prone to decomposition into NaOH and NaO2, was previously thought to be impossible to obtain in pure form.[7]
However, with the help of cryptands and methylamine, pure NaO3 may be obtained as red crystals isostructural to NaNO2.[8]
Ionic ozonides are being investigated[senza fonte] as sources of oxygen in chemical oxygen generators. Tetramethylammonium ozonide, which can be made by a metathesis reaction with caesium ozonide in liquid ammonia, is stable up to 348K:
- CsO3 + [(CH3)4N][O2] → CsO2 + [(CH3)4N][O3]
Chimica organica[modifica | modifica wikitesto]
L'ozono può addizionarsi ai doppi legami di una molecola organica, con formazione di gruppi ciclici, detti ozonuri. La reazione avviene in due fasi:
- addizione dell'ozono al doppio legame, con formazione di un composto detto molozonuro;
- riarrangiamento del molozonuro nell'ozonuro.
Gli ozonuri sono anche chiamati triossolani.
Trattando un ozonuro con acqua e zinco metallico, l'anello dell'ozonuro si rompe e si riduce parzialmente formando due aldeidi. Tale reazione era usata in chimica analitica organica per definire la posizione di un doppio legame.
Strutture legame singolo covalente[modifica | modifica wikitesto]
Phosphite ozonides, (RO)3PO3, are used in the production of singlet oxygen. They are made by ozonizing a estere fosfite in dichloromethane at low temperatures, and decompose to yield singlet oxygen and a phosphate ester:[9]
- (RO)3P + O3 → (RO)3PO3
- (RO)3PO3 → (RO)3PO + 1O2
Ozoniuro radicale[modifica | modifica wikitesto]
Organic ozonides are called molozonides and are typically formed by the addition reaction between ozone and alkenes. They are more explosive cousins of the organic peroxides and as such are rarely isolated during the course of the ozonolysis reaction sequence. Molozonides are unstable and rapidly convert to the trioxolane ring structure with a five-membered C–O–O–C–O ring.[10][11] They usually appear in the form of foul-smelling oily liquids, and rapidly decompose in the presence of water to carbonyl compounds: aldehydes, ketones, peroxides.
Note[modifica | modifica wikitesto]
- ^ Nomenclature of Inorganic Chemistry : IUPAC Recommendations 2005 (Red Book), Cambridge, The Royal Society of Chemistry, 2005, p. 315, ISBN 978-0-85404-438-2.
- ^ a b aminyl (CHEBI:29318), in Chemical Entities of Biological Interest (ChEBI), European Bioinformatics Institute.
- ^ scheda del composto su IFA-GESTIS
- ^ (EN) IUPAC Gold Book, "ozonides"
- ^ F.A. Cotton and G. Wilkinson "Advanced Inorganic Chemistry", 5th edition (1988)
- ^ F. A. Cotton and G. Wilkinson "Advanced Inorganic Chemistry", 5th edition (1988), p.462
- ^ Ionic Ozonides of Lithium and Sodium: Circumventive Synthesis by Cation Exchange in Liquid Ammonia and Complexation by Cryptands, in Chemische Berichte, vol. 129, n. 7, 1996, pp. 773–777, DOI:10.1002/cber.19961290707.
- ^ Synthesis and crystal structure determination of sodium ozonide, in Chemical Communications, n. 6, 1998, pp. 707–708, DOI:10.1039/a708570b.
- ^ Chapter 16: The group 16 elements, in Inorganic Chemistry, 3rd Edition, Pearson, 2008, p. 496, ISBN 978-0-13-175553-6.
- ^ Mechanism of Ozonolysis, in Angewandte Chemie International Edition in English, vol. 14, n. 11, pp. 745–752, DOI:10.1002/anie.197507451.
- ^ https://www.organic-chemistry.org/namedreactions/ozonolysis-criegee-mechanism.shtm Ozonolysis mechanism on Organic Chemistry Portal site
Voci correlate[modifica | modifica wikitesto]
- Ozonolisi
- Ozono
- Ozone cracking
- Superossido, O−2
- Perossido, O2−2
- Ossido, O2−
- Diossigenile, O+2
Collegamenti esterni[modifica | modifica wikitesto]
