Phenolates (also called phenoxides) are

anion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...

salts In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions ( cations) and negatively charged ions (anions), which results in a compound with no net electric charge (electrically neutral). ...

, and esters of

phenols In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (− O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds ar ...

, containing the phenolate ion. They may be formed by reaction of phenols with strong base.

Properties

Alkali metal phenolates, such as

sodium phenolate Sodium phenoxide (sodium phenolate) 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 ...

hydrolyze in aqueous solution to form basic solutions. At pH = 10, phenol and phenolate are in approximately 1:1 proportions. The phenoxide anion (aka

phenolate Phenolates (also called phenoxides) are anions, salt (chemistry), salts, and esters of phenols, containing the phenolate ion. They may be formed by reaction of phenols with strong base. Properties Alkali metal phenolates, such as sodium phenoxi ...

) is a strong

nucleophile In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are ...

with a comparable to the one of carbanions or tertiary amines. Generally, oxygen attack of phenoxide anions is kinetically favored, while carbon-attack is thermodynamically preferred (see

Thermodynamic versus kinetic reaction control Thermodynamic reaction control or kinetic reaction control in a chemical reaction can decide the composition in a reaction product mixture when competing pathways lead to different products and the reaction conditions influence the selectivity o ...

). Mixed oxygen/carbon attack and by this a loss of selectivity is usually observed if the reaction rate reaches diffusion control.

Uses

Alkyl aryl ethers can be synthesized through the

Williamson ether synthesis The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol (alkoxide). This reaction was developed by Alexander Williamson in 1850. Typically it involves the reaction of an alkoxide ...

by treating sodium phenolate with an

alkyl halide The haloalkanes (also known as halogenoalkanes or alkyl halides) are alkanes containing one or more halogen substituents of hydrogen atom. They are a subset of the general class of halocarbons, although the distinction is not often made. Haloalka ...

: :C₆H₅ONa + CH₃I → C₆H₅OCH₃ + NaI :C₆H₅ONa + (CH₃O)₂SO₂ → C₆H₅OCH₃ + (CH₃O)SO₃Na

Production of salicylic acid

Salicylic acid is produced in the

Kolbe–Schmitt reaction The Kolbe–Schmitt reaction or Kolbe process (named after Hermann Kolbe and Rudolf Schmitt) is a carboxylation chemical reaction that proceeds by treating phenol with sodium hydroxide to form sodium phenoxide, then heating sodium phenoxide wi ...

between carbon dioxide and sodium phenolate. : Salicylic-Acid_General_Synthesis_V

References

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Properties

Uses

Production of salicylic acid

See also

References