Sodium phenoxide

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by DMacks (talk | contribs) at 20:33, 27 July 2018 (→‎Synthesis and structure: link). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Sodium phenoxide
Names
Other names
Sodium phenolate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.004.862 Edit this at Wikidata
  • 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
  • c1ccc(cc1)[O-].[Na+]
Properties
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).

Sodium phenoxide is an organic compound with the formula NaOC6H5. It is a white crystalline solid. Its anion, phenoxide, also known as phenolate, 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 structure 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-type cluster [NaOPh]4(HMPA)4.[2]

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

C6H5SO3Na + 2 NaOH → C6H5ONa + Na2SO3

This route once was the principal industrial route to phenol.

Ball-and-stick model of the sodium coordination geometry in unsolvated sodium phenoxide Space-filling model of part of a chain in the crystal structure of unsolvated sodium phenoxide

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. ^ a b 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 978-0-471-72091-1

External links

Media related to Sodium phenoxide at Wikimedia Commons