Potassium tert-butoxide: physicochemical property and Application

Physicochemical Property

Potassium tert-butoxide is also known as Potassium 2-methylpropan-2-olate or t-BuOK.

Molecular weight: 112.21; Molecular formula: KOC(CH3)3. 

Appearance: white to light yellow powder to crystal

Density: 0.902 g/mL at 25 °C

Melting point: 240 °C

Hygroscopic.

Soluble in ether.

It should be stored and handled under inert atmosphere. It is a strong non-nucleophilic base. Its conjugate acid has a pKa of about 17. Similar bases include tert-butanol sodium (t-BuONa) and tert-butanol lithium (t-BuOLi).

Potassium tert-butoxide reagent solutions can be prepared by reacting anhydrous ethanol with potassium in a nitrogen atmosphere.

Application of Potassium tert-butoxide

Potassium tert-butoxide solution(t-BuOK) can be used:

• As a catalyst for the interesterification of rapeseed oil with methyl acetate.
  

• To promote Sommelet–Hauser rearrangements of N-benzylic amino acid-derived ammonium ylides under mild conditions.

• As a metal-organic precursor in the synthesis of KNbO3 ferroelectric films by the chemical vapor deposition method.  
  

• To prepare 3-potassiooxamethylpyridine catalyst.
  

• As a strong alkoxide base reagent.
  

• Potassium tert‐Butoxide Mediated Synthesis of Phenanthridinone.
  

• As a catalyst for the synthesis of γ-butenolide
  

References:

[1] GUANGFEN DU. Diastereoselective Synthesis of γ-Butenolides Catalyzed by Potassium tert-Butoxide[J]. Synthetic Communications, 2012. DOI:10.1080/00397911.2010.538888.

[2] WANG Y. Potassium tert-Butoxide[J]. Synlett, 2011. DOI:10.1055/S-0031-1289873.

[3] B. S. BHAKUNI. Potassium tert‐Butoxide Mediated Synthesis of Phenanthridinone[J]. Organic Syntheses, 2014. DOI:10.1002/0471264229.OS090.16.