Sodium phenoxide

Sodium phenoxide

Names
Other names Sodium phenolate
Identifiers
CAS Number	139-02-6
3D model (Jmol)	Interactive image
ChemSpider	8420
ECHA InfoCard	100.004.862
PubChem	4445035
InChI InChI=1S/C6H6O.Na/c7-6-4-2-1-3-5-6;/h1-5,7H;/q;+1/p-1 Key: NESLWCLHZZISNB-UHFFFAOYSA-M InChI=1/C6H6O.Na/c7-6-4-2-1-3-5-6;/h1-5,7H;/q;+1/p-1 Key: NESLWCLHZZISNB-REWHXWOFAP
SMILES c1ccc(cc1)[O-].[Na+]
Properties
Chemical formula	C6H5NaO
Molar mass	116.09 g/mol
Appearance	White solid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Sodium phenoxide is an organic compound with the formula NaOC₆H₅. This white solid is the conjugate base of phenol. It is used as a precursor to many other organic compounds, such as aryl ethers.

Synthesis and structure

Most commonly, solutions of sodium phenoxide are produced by treating phenol with sodium hydroxide.^[1] Anhydrous derivatives can be prepared from phenol and sodium:

Na + HOC₆H₅ → NaOC₆H₅ + 1/2 H₂

Like other sodium alkoxides, crystalline sodium phenolate adopts a complex structures involving multiple Na-O bonds. Solvent-free material is polymeric, each Na center being bound to three oxygen ligands as well as the phenyl ring. Adducts of sodium phenoxide are molecular, such as the cubane [NaOPh]₄(HMPA)₄.^[2]

Sodium phenoxide is produced by the "alkaline fusion" of benzenesulfonic acid, whereby the sulfonate groups is displaced by hydroxide:

C₆H₅SO₃Na + 2 NaOH → C₆H₅ONa + Na₂SO₃

This route once was the principal industrial route to phenol.

Reactions

Sodium phenoxide is a moderately strong base. At low pH's gives phenol:^[3]

PhOH ⇌ PhO⁻ + H⁺          (K = 10⁻¹⁰)

Sodium phenoxide can be used to prepare phenyl ethers and metal phenolates:^[1]

NaOC₆H₅ + RBr → ROC₆H₅ + NaBr

References

1. C. S. Marvel and A. L. Tanenbaum "γ-Phenoxypropyl Bromide" Org. Synth. 1929, vol. 9, pp. 72.
2. Michael Kunert, Eckhard Dinjus, Maria Nauck, Joachim Sieler "Structure and Reactivity of Sodium Phenoxide - Following the Course of the Kolbe-Schmitt Reaction" Chemische Berichte 1997 Volume 130, Issue 10, pages 1461–1465. doi:10.1002/cber.19971301017
3. Smith, Michael B.; March, Jerry (2007), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (6th ed.), New York: Wiley-Interscience, ISBN 0-471-72091-7

External links

Media related to Sodium phenoxide at Wikimedia Commons