![]() ![]() ^ disassociation constant of ethanol, referenced in the CRC Handbook of Chemistry and Physics 87th edition.It has been reported that even newly-obtained commercial batches of sodium ethoxide show variable levels of degradation, and responsible as a major source of irreproducibility when used in Suzuki reactions. The physical appearance of degraded samples may not be obvious, but samples of sodium ethoxide gradually turn dark on storage. This leads to degradation of stored samples over time, even in solid form. Sodium ethoxide is prone to reaction with both water and carbon dioxide in the air. Many alkoxides are prepared by salt metathesis from sodium ethoxide. In practice, the alcohol/alkoxide solvating mixture must match the alkoxy components of the reacting esters to minimize the number of different products. If the starting material is an ethyl ester, trans-esterification is irrelevant since the product is identical to the starting material. Sodium ethoxide may either deprotonate the α-position of an ester molecule, forming an enolate, or the ester molecule may undergo a nucleophilic substitution called transesterification. Sodium ethoxide is commonly used as a base in the Claisen condensation and malonic ester synthesis. Its crystal structure has been determined, although the structure of other phases in the Na/EtOH system remain unknown. The reaction of sodium and ethanol sometimes forms other products such as the disolvate NaOEt♲EtOH. The ethyl layers pack back-to-back resulting in a lamellar structure. It consists of layers of alternating Na + and O − centres with disordered ethyl groups covering the top and bottom of each layer. The crystal structure of sodium ethoxide has been determined by X-ray crystallography. The reaction of sodium hydroxide with anhydrous ethanol suffers from incomplete conversion to the alkoxide. It is easily prepared in the laboratory by treating sodium metal with absolute ethanol: 2C 2H 5OH + 2Na → 2C 2H 5ONa + H 2 It is commercially available and as a solution in ethanol. Instead the material is typically prepared in a solution with ethanol. Preparation įew procedures have been reported to prepare the anhydrous solid. It dissolves in polar solvents such as ethanol. It is a white solid, although impure samples appear yellow or brown. ![]() Sodium ethoxide, also referred to as sodium ethylate, is the ionic, organic compound with the formula C 2H 5ONa, or NaOEt (Et = ethane). ![]()
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