What Is Cesium Carbonate?
Cesium carbonate is a carbonate of cesium with the formula Cs2CO3 (molecular weight 325.82).
It is a white crystalline solid, highly soluble in polar solvents like water, alcohol, and DMF. It should be handled carefully in the air as it absorbs moisture and can dissolve.
Used as a strong inorganic base or catalyst in organic synthesis, cesium carbonate facilitates stereoselective coupling reactions. It decomposes at 1112° F (600°C), producing non-volatile decomposition products upon heating.
Its conductive properties make it useful in solar cell applications to enhance power conversion efficiency.
Uses of Cesium Carbonate
Primarily used as an inorganic base and catalyst in organic synthesis, cesium carbonate excels in carbonylation and carbamoylation coupling reactions, including the Heck and Sonogashira reactions. It is a balanced, strong base for intricate syntheses.
It is also utilized in cathodes for organic electronic materials. Decomposing into Cs2O and Cs2O2 at high temperatures, cesium carbonate enables n-type doping in semiconductors, increasing power conversion efficiency in electronic devices.
Properties of Cesium Carbonate
Cesium carbonate has greater solubility in organic solvents compared to other alkali metal carbonates, due to cesium’s large atomic radius and easy cationization.
Its low charge density allows it to readily dissociate with anions in organic solvents, a property useful in synthetic reactions. However, it’s insoluble in low-polarity solvents like toluene, p-xylene, and chlorobenzene.
While similar to other carbonate compounds, its high cost limits its use in reactions where cheaper bases can substitute.
Structure of Cesium Carbonate
Cesium carbonate, a salt consisting of cesium ions and carbonate ions, comes in anhydrous and trihydrate forms. Cesium’s position in period 6 of the periodic table contributes to its low ionization energy and low charge density, facilitating ion dissociation in solutions.
Other Information on Cesium Carbonate
Production Process of Cesium Carbonate
Cesium carbonate is produced by heating cesium oxalate, which forms cesium carbonate and carbon monoxide upon decomposition.
Cs2C2O4 → Cs2CO3 + CO
Alternatively, cesium carbonate can be synthesized by reacting cesium hydroxide with carbon dioxide. Passing carbon dioxide gas through an aqueous solution of cesium hydroxide results in cesium carbonate, which is then isolated by evaporating the solution to dryness.