Names | |
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Other names Sodium ethanolate, sodium ethylate (obsolete) | |
Identifiers | |
3D model (JSmol) | |
3593646 | |
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.004.989 |
EC Number |
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PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
CH3CH2ONa | |
Molar mass | 68.051 g·mol−1 |
Appearance | White hygroscopic powder |
Density | 0.868 g/cm3 (of a 21 wt% solution in ethanol) |
Melting point | 260 °C (500 °F; 533 K) |
Reacts | |
Solubility | ethanol and methanol |
Acidity (pKa) | 15.5 [1] |
Hazards | |
GHS labelling: | |
Danger | |
H228, H251, H302, H314 | |
P210, P235+P410, P240, P241, P260, P264, P270, P280, P301+P312, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P330, P363, P370+P378, P405, P407, P413, P420, P501 | |
NFPA 704 (fire diamond) | |
Safety data sheet (SDS) | Oxford MSDS |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Sodium ethoxide, also referred to as sodium ethanolate, is the ionic, organic compound with the formula CH3CH2ONa, C 2 H 5 O Na , or NaOEt (Et = ethyl). It is a white solid, although impure samples appear yellow or brown. It dissolves in polar solvents such as ethanol. It is commonly used as a strong base. [2]
Few procedures have been reported to prepare the anhydrous solid. Instead the material is typically prepared in a solution with ethanol. It is commercially available and as a solution in ethanol. It is easily prepared in the laboratory by treating sodium metal with absolute ethanol: [3]
The reaction of sodium hydroxide with anhydrous ethanol suffers from incomplete conversion to the ethoxide.
The crystal structure of sodium ethoxide has been determined by X-ray crystallography. It consists of layers of alternating Na+ and O− centres with disordered ethyl groups covering the top and bottom of each layer. The ethyl layers pack back-to-back resulting in a lamellar structure. The reaction of sodium and ethanol sometimes forms other products such as the disolvate CH3CH2ONa·2CH3CH2OH . Its crystal structure has been determined, although the structure of other phases in the CH3CH2ONa/CH3CH2OH system remain unknown. [4]
ball-and-stick model of layer stacking in the crystal structure of CH3CH2ONa | coordination geometry at Na | coordination geometry at O |
Sodium ethoxide is commonly used as a base in the Claisen condensation [5] and malonic ester synthesis. [6] 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. If the starting material is an ethyl ester, trans-esterification is irrelevant since the product is identical to the starting material. In practice, the alcohol/alkoxide solvating mixture must match the alkoxy components of the reacting esters to minimize the number of different products.
Many alkoxides are prepared by salt metathesis from sodium ethoxide.
Sodium ethoxide is prone to reaction with both water and carbon dioxide in the air. [7] This leads to degradation of stored samples over time, even in solid form. The physical appearance of degraded samples may not be obvious, but samples of sodium ethoxide gradually turn dark on storage. 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. [7]
In moist air, CH3CH2ONa hydrolyses rapidly to sodium hydroxide (NaOH). The conversion is not obvious and typical samples of CH3CH2ONa are contaminated with NaOH.
In moisture-free air, solid sodium ethoxide can form sodium ethyl carbonate from fixation of carbon dioxide from the air. Further reactions lead to degradation into a variety of other sodium salts and diethyl ether. [7]
This instability can be prevented by storing sodium ethoxide under an inert atmosphere (e.g., N2).
Sodium ethoxide is a strong base, and is therefore corrosive.
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst. The hydroxide ion forms salts, some of which dissociate in aqueous solution, liberating solvated hydroxide ions. Sodium hydroxide is a multi-million-ton per annum commodity chemical. The corresponding electrically neutral compound HO• is the hydroxyl radical. The corresponding covalently bound group –OH of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry.
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na+ and hydroxide anions OH−.
Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.
In chemistry, the alkoxy group is an alkyl group which is singularly bonded to oxygen; thus R−O. The range of alkoxy groups is vast, the simplest being methoxy. An ethoxy group is found in the organic compound ethyl phenyl ether.
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties react to form a β-hydroxyaldehyde or β-hydroxyketone, and this is then followed by dehydration to give a conjugated enone.
Diethyl malonate, also known as DEM, is the diethyl ester of malonic acid. It occurs naturally in grapes and strawberries as a colourless liquid with an apple-like odour, and is used in perfumes. It is also used to synthesize other compounds such as barbiturates, artificial flavourings, vitamin B1, and vitamin B6.
Sodium acetate, CH3COONa, also abbreviated NaOAc, is the sodium salt of acetic acid. This colorless deliquescent salt has a wide range of uses.
The Claisen condensation is a carbon–carbon bond forming reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base. The reaction produces a β-keto ester or a β-diketone. It is named after Rainer Ludwig Claisen, who first published his work on the reaction in 1887. The reaction has often been displaced by diketene-based chemistry, which affords acetoacetic esters.
A xanthate is a salt or ester of a xanthic acid. The formula of the salt of xanthic acid is [R−O−CS2]−M+ ,. Xanthate also refers to the anion [R−O−CS2]−. The formula of a xanthic acid is R−O−C(=S)−S−H, such as ethyl xanthic acid, while the formula of an ester of a xanthic acid is R−O−C(=S)−S−R', where R and R' are organyl groups. The salts of xanthates are also called O-organyl dithioates. The esters of xanthic acid are also called O,S-diorganyl esters of dithiocarbonic acid. The name xanthate is derived from Ancient Greek ξανθός xanthos, meaning “yellowish, golden”, and indeed most xanthate salts are yellow. They were discovered and named in 1823 by Danish chemist William Christopher Zeise. These organosulfur compounds are important in two areas: the production of cellophane and related polymers from cellulose and for extraction of certain sulphide bearing ores. They are also versatile intermediates in organic synthesis.
Triethyl orthoformate is an organic compound with the formula HC(OC2H5)3. This colorless volatile liquid, the orthoester of formic acid, is commercially available. The industrial synthesis is from hydrogen cyanide and ethanol.
Sodium hydrosulfide is the chemical compound with the formula NaSH. This compound is the product of the half-neutralization of hydrogen sulfide with sodium hydroxide (NaOH). NaSH and sodium sulfide are used industrially, often for similar purposes. Solid NaSH is colorless. The solid has an odor of H2S owing to hydrolysis by atmospheric moisture. In contrast with sodium sulfide, which is insoluble in organic solvents, NaSH, being a 1:1 electrolyte, is more soluble.
Sodium methoxide is the simplest sodium alkoxide. With the formula CH3ONa, it is a white solid, which is formed by the deprotonation of methanol. It is a widely used reagent in industry and the laboratory. It is also a dangerously caustic base.
In organic chemistry, the acetoxy group, is a functional group with the formula −OCOCH3 and the structure −O−C(=O)−CH3. As the -oxy suffix implies, it differs from the acetyl group by the presence of an additional oxygen atom. The name acetoxy is the short form of acetyl-oxy.
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 compounds, such as aryl ethers.
Organosodium chemistry is the chemistry of organometallic compounds containing a carbon to sodium chemical bond. The application of organosodium compounds in chemistry is limited in part due to competition from organolithium compounds, which are commercially available and exhibit more convenient reactivity.
Potassium ethyl xanthate (KEX) is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores. It is a potassium salt of ethyl xanthic acid.
Potassium methoxide is the alkoxide of methanol with the counterion potassium and is used as a strong base and as a catalyst for transesterification, in particular for the production of biodiesel.
Potassium ethoxide, also known as potassium ethanolate, is an off-white or yellow powder with the chemical formula of C2H5KO. Potassium ethoxide contains an ethoxide ion, the conjugate base of ethanol, which makes this compounds strongly basic. It hydrolyzes to yield ethanol and potassium hydroxide.
Etabonate or ethyl carbonate is the chemical group with formula –CO
3–C
2H
5, or H
3C–CH
2–O–C(=O)–O–. The names are also used for esters R–OCO
2C
2H
5, for the anion [C
2H
5OCO−
2], and for salts of the latter.
In chemistry, an alkoxide is the conjugate base of an alcohol and therefore consists of an organic group bonded to a negatively charged oxygen atom. They are written as RO−, where R is the organyl substituent. Alkoxides are strong bases and, when R is not bulky, good nucleophiles and good ligands. Alkoxides, although generally not stable in protic solvents such as water, occur widely as intermediates in various reactions, including the Williamson ether synthesis. Transition metal alkoxides are widely used for coatings and as catalysts.