Sodium cyanate explained

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:

The salt adopts a body centered rhombohedral crystal lattice structure (trigonal crystal system) at room temperature.^[1]

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 + H₂OSodium allophanate is observed as an intermediate:^[2]

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.^[2]

Sodium cyanate is used to produce cyanic acid, often in situ:

This approach is exploited for condensation with amines to give unsymmetrical ureas:

Such urea derivatives have a range of biological activity.^[3]

See also

• Cyanate

Notes and References

1. 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.
2. Book: 10.1002/14356007.a08_157.pub2 . Cyanates, Inorganic Salts . Ullmann's Encyclopedia of Industrial Chemistry . 2006 . Schalke . Peter M. . 3527306730 .
3. Vinogradova. Ekaterina V.. Fors. Brett P.. Buchwald. Stephen L.. Palladium-Catalyzed Cross-Coupling of Aryl Chlorides and Triflates with Sodium Cyanate: A Practical Synthesis of Unsymmetrical Ureas. Journal of the American Chemical Society. 11 July 2012. 134. 27. 11132–11135. 10.1021/ja305212v. 3472423. 22716197.