| |
| Identifiers | |
|---|---|
| CAS Number | |
| 3D model (JSmol) | |
| Beilstein Reference | 3655041 |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.011.846 
|
| EC Number |
|
| MeSH | C009281 |
| PubChem CID | |
| UNII | |
| CompTox Dashboard (EPA) | |
InChI
| |
SMILES
| |
| Properties | |
| Chemical formula | NaOCN |
| Molar mass | 65.01 g/mol |
| Appearance | white crystalline solid |
| Odor | odorless |
| Density | 1.893 g/cm |
| Melting point | 550 °C (1,022 °F; 823 K) |
| Solubility in water | 11.6 g/100 mL (25 °C) |
| Solubility | ethanol: 0.22 g/100 mL (0 °C) dimethylformamide: 0.05 g/100 mL (25 °C) slightly soluble in ammonia, benzene insoluble in diethyl ether |
| Structure | |
| Crystal structure | body centered rhombohedral |
| Thermochemistry | |
| Heat capacity (C) | 86.6 J/mol K |
| Std molar entropy (S298) |
119.2 J/mol K |
| Std enthalpy of formation (ΔfH298) |
−400 kJ/mol |
| Hazards | |
| GHS labelling: | |
| Pictograms | 
|
| Signal word | Warning |
| Hazard statements | H302, H412 |
| Precautionary statements | P264, P270, P273, P301+P312, P330, P501 |
| Lethal dose or concentration (LD, LC): | |
| LD50 (median dose) | 1500 mg/kg (rat, oral) |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). Infobox references | |
Sodium cyanate is the inorganic compound with the formula NaOCN. A white solid, it is the sodium salt of the cyanate anion.
Structure
The anion is described by two resonance structures: N≡C−O and N=C=O
The salt adopts a body centered rhombohedral crystal lattice structure (trigonal crystal system) at room temperature.
Preparation
Sodium cyanate is prepared industrially by the reaction of urea with sodium carbonate at elevated temperature.
- 2OC(NH2)2 + Na2CO3 → 2Na(NCO) + CO2 + 2NH3 + H2O
Sodium allophanate is observed as an intermediate:
- H2NC(O)NHCO2Na → NaOCN + NH3 + CO2
It can also be prepared in the laboratory by oxidation of a cyanide in aqueous solution by a mild oxidizing agent such as lead oxide.
Uses and reactions
The main use of sodium cyanate is for steel hardening.
Sodium cyanate is used to produce cyanic acid, often in situ:
- NaOCN + HCl → HOCN + NaCl
This approach is exploited for condensation with amines to give unsymmetrical ureas:
- HOCN + RNH2 → RNHC(O)NH2
Such urea derivatives have a range of biological activity.
See also
References
- Waddington, T.C. "Journal of the Chemical Society (Resumed)." 499. Lattice Parameters and Infrared Spectra of Some Inorganic Cyanates - (RSC Publishing). N.p., n.d. Web. 09 Nov. 2014.
- ^ Schalke, Peter M. (2006). "Cyanates, Inorganic Salts". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a08_157.pub2. ISBN 3527306730.
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 324. ISBN 978-0-08-037941-8.
- Vinogradova, Ekaterina V.; Fors, Brett P.; Buchwald, Stephen L. (11 July 2012). "Palladium-Catalyzed Cross-Coupling of Aryl Chlorides and Triflates with Sodium Cyanate: A Practical Synthesis of Unsymmetrical Ureas". Journal of the American Chemical Society. 134 (27): 11132–11135. doi:10.1021/ja305212v. PMC 3472423. PMID 22716197.
| Sodium compounds | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inorganic |
| ||||||||||||||
| Organic | |||||||||||||||
| Salts and covalent derivatives of the cyanate ion | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 | This inorganic compound–related article is a stub. You can help Misplaced Pages by expanding it. |