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Sodium Phenoxide
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. Synthesis and structure 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 → C6H5ONa + 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union Of Pure And Applied Chemistry
The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is a member of the International Science Council (ISC). IUPAC is registered in Zürich, Switzerland, and the administrative office, known as the "IUPAC Secretariat", is in Research Triangle Park, North Carolina, United States. This administrative office is headed by IUPAC's executive director, currently Lynn Soby. IUPAC was established in 1919 as the successor of the International Congress of Applied Chemistry for the advancement of chemistry. Its members, the National Adhering Organizations, can be national chemistry societies, national academies of sciences, or other bodies representing chemists. There are fifty-four National Adhering Organizations and three Associate National Adhering Organizations. IUPAC's Inter-divisional Committee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMPA
Hexamethylphosphoramide, often abbreviated HMPA, is a phosphoramide (an amide of phosphoric acid) with the formula This colorless liquid is a useful reagent in organic synthesis. Structure and reactivity HMPA is the oxide of the highly basic tertiary phosphine hexamethylphosphorous triamide (HMPT), P(NMe2)3. Like other phosphine oxides (such as triphenylphosphine oxide), the molecule has a tetrahedral core and a P=O bond that is highly polarized, with significant negative charge residing on the oxygen atom. Compounds containing a nitrogen–phosphorus bond typically are degraded by hydrochloric acid to form a protonated amine and phosphate. It dissolves alkali metal salts and alkali metals, forming blue solutions which are stable for a few hours. Solvated electrons are present in these blue solutions. Applications HMPA is a specialty solvent for polymers, gases, and organometallic compounds. It improves the selectivity of lithiation reactions by breaking up the oligomers of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salicylic Acid
Salicylic acid is an organic compound with the formula HOC6H4CO2H. A colorless, bitter-tasting solid, it is a precursor to and a metabolite of aspirin (acetylsalicylic acid). It is a plant hormone, and has been listed by the EPA Toxic Substances Control Act (TSCA) Chemical Substance Inventory as an experimental teratogen. The name is from Latin '' salix'' for willow tree. It is an ingredient in some anti-acne products. Salts and esters of salicylic acid are known as salicylates. Uses Medicine Salicylic acid as a medication is commonly used to remove the outer layer of the skin. As such, it is used to treat warts, psoriasis, acne vulgaris, ringworm, dandruff, and ichthyosis. Similar to other hydroxy acids, salicylic acid is an ingredient in many skincare products for the treatment of seborrhoeic dermatitis, acne, psoriasis, calluses, corns, keratosis pilaris, acanthosis nigricans, ichthyosis, and warts. Uses in manufacturing Salicylic acid is used as a food p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophilic Aromatic Substitution
Electrophilic aromatic substitution is an organic reaction in which an atom that is attached to an aromatic system (usually hydrogen) is replaced by an electrophile. Some of the most important electrophilic aromatic substitutions are aromatic nitration, aromatic halogenation, aromatic sulfonation, and alkylation and acylation Friedel–Crafts reaction. Illustrative reactions The most widely practised example of this reaction is the ethylation of benzene. :: Approximately 24,700,000 tons were produced in 1999. (After dehydrogenation and polymerization, the commodity plastic polystyrene is produced.) In this process, acids are used as catalyst to generate the incipient carbocation. Many other electrophilic reactions of benzene are conducted, although on a much smaller scale; they are valuable routes to key intermediates. The nitration of benzene is achieved via the action of the nitronium ion as the electrophile. The sulfonation with fuming sulfuric acid gives benzenesulfoni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Williamson Ether Synthesis The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol ( alkoxide). This reaction was developed by Alexander Williamson in 1850. Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an SN2 reaction. This reaction is important in the history of organic chemistry because it helped prove the structure of ethers. The general reaction mechanism is as follows: An example is the reaction of sodium ethoxide with chloroethane to form diethyl ether and sodium chloride: :C2H5Cl + C2H5ONa -> C2H5OC2H5 + NaCl Mechanism The Williamson ether reaction follows an SN2 bimolecular nucleophilic substitution mechanism. In an SN2 reaction mechanism there is a backside attack of an electrophile by a nucleophile and it occurs in a concerted mechanism (happens all at once). In order for the SN2 reaction to take place there must be a good leaving group which is strongly electronegative, commonly a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
