Sodium phenoxide

Most commonly, solutions of sodium phenoxide are produced by treating phenol with sodium hydroxide. Anhydrous derivatives can be prepared by combining phenol and sodium. A related, updated procedure uses sodium methoxide instead of sodium hydroxide: :NaOCH3 + HOC6H5 → NaOC6H5 + HOCH3 Sodium phenoxide can also be produced by the "alkaline fusion" of benzenesulfonic acid, whereby the sulfonate groups are displaced by hydroxide: :C6H5SO3Na + 2 NaOH → C6H5OH + Na2SO3 This route once was the principal industrial route to phenol. ==Structure==

Like other sodium alkoxides, solid sodium phenoxide 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. ==Reactions==

Sodium phenoxide is a moderately strong base. Acidification gives phenol: :PhOH ⇌ PhO− + H+          (K = 10−10) The acid-base behavior is complicated by homoassociation, reflecting the association of phenol and phenoxide. Sodium phenoxide reacts with alkylating agents to afford alkyl phenyl ethers: :NaOC6H5 + RBr → ROC6H5 + NaBr The conversion is an extension of the Williamson ether synthesis. With acylating agents, one obtains phenyl esters: :NaOC6H5 + RC(O)Cl → RCO2C6H5 + NaCl Sodium phenoxide is susceptible to certain types of electrophilic aromatic substitutions. For example, it reacts with carbon dioxide to form 2-hydroxybenzoate, the conjugate base of salicylic acid. In general however, electrophiles irreversibly attack the oxygen center in phenoxide. :. ==References==