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Triton B
Benzyltrimethylammonium hydroxide, also known as Triton B or trimethylbenzylammonium hydroxide, is a quaternary ammonium salt that functions as an organic base. It is usually handled as a solution in water or methanol. The compound is colourless, although the solutions often appear yellowish. Commercial samples often have a distinctive fish-like odour, presumably due to the presence of trimethylamine via hydrolysis. Uses Together with the benzyltriethylammonium salt, benzyltrimethylammonium hydroxide is a popular phase-transfer catalyst. It is used in aldol condensation reactions and base-catalyzed dehydration reactions. It is also used as a base in Ando's Z-selective variant of Horner-Wadsworth-Emmons Olefination reactions. Relative to tetramethylammonium hydroxide, benzyltriethylammonium hydroxide is more labile. In 6M NaOH at 160 °C their half-lives are 61.9 and 4 h, respectively.{{cite journal , doi=10.1002/cssc.201403022, title=Alkaline Stability of Quaternary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Ammonium Salt
In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure , where R is an alkyl group, an aryl group or organyl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule. Quats are used in consumer applications including as antimicrobials (such as detergents and disinfectants), fabric softeners, and hair conditioners. As an antimicrobial, they are able to inactivate enveloped viruses (such as SARS-CoV-2). Quats tend to be gentler on surfaces than bleach-based disinfectants, and are generally fabric-safe. Synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, Volatility (chemistry), volatile, colorless and flammable liquid with a distinctive alcoholic odor similar to that of ethanol (potable alcohol), but is more acutely toxic than the latter. Methanol acquired the name wood alcohol because it was once produced through destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a Precursor (chemistry), precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl ''tert''-butyl ether, methyl benzoate, anisole, peroxyacids, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzyltriethylammonium Hydroxide
Benzyltriethylammonium hydroxide is a quaternary ammonium salt In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure , where R is an alkyl group, an aryl group or organyl group. Unlike the ammonium ion () and the primary, secondary, ... that functions as an organic base. Uses Together with benzyltrimethylammonium hydroxide, salts of benzyltriethylammonium are common phase-transfer catalysts. References Hydroxides Quaternary ammonium compounds Reagents for organic chemistry Benzyl compounds {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase-transfer Catalyst
In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the Phase transition, transition of a reactant from one phase (matter), phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catalyst used. Ionic compound, Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase in the absence of the phase-transfer catalyst. The catalyst functions like a detergent for solubilizing the salts into the organic phase. Phase-transfer catalysis refers to the acceleration of the reaction upon the addition of the phase-transfer catalyst. PTC is widely exploited industrially.Marc Halpern "Phase-Transfer Catalysis" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. Polyesters for example are prepared from acyl chlorides and Bisphenol A, bisphenol-A. Phosphothioate-based pesticides a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldol Condensation
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to give a conjugated enone. The overall reaction equation is as follows (where the Rs can be H) Aldol condensations are important in organic synthesis and biochemistry as ways to form carbon–carbon bonds. In its usual form, it involves the nucleophilic addition of a ketone enolate to an aldehyde to form a β-hydroxy ketone, or aldol (aldehyde + alcohol), a structural unit found in many naturally occurring molecules and pharmaceuticals. The term ''aldol condensation'' is also commonly used, especially in biochemistry, to refer to just the first (addition) stage of the process—the aldol reaction itself—as catalyzed by aldolases. However, the first step is formally an addition reaction rather than a condensation reaction bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration Reaction
In chemistry, a dehydration reaction is a chemical reaction that involves the loss of an H2O from the reacting molecule(s) or ion(s). This reaction results in the release of the H2O as water. When the reaction involves the coupling of two molecules into a single molecule it is referred to as a condensation reaction. Dehydration reactions are common processes in the manufacture of chemical compounds as well as naturally occurring within living organisms. The reverse of a dehydration reaction is called a hydration reaction. The reverse of a condensation reaction yielding water is called hydrolysis. Condensation reactions occurring in living organisms Condensation dehydration reactions are fundamental to the existence of life as this type of reaction produces proteins from amino acids, DNA and RNA from nucleotides, fats from fatty acids, and polysaccharides (eg. cellulose, starch, sugar, lactose) from monosaccharides (eg. glucose and fructose). The formation of the pyrophosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horner–Wadsworth–Emmons Reaction
The Horner–Wadsworth–Emmons (HWE) reaction is a chemical reaction used in organic chemistry of stabilized phosphonate carbanions with aldehydes (or ketones) to produce predominantly E-alkenes. In 1958, Leopold Horner published a modified Wittig reaction using phosphonate-stabilized carbanions. William S. Wadsworth and William D. Emmons further defined the reaction. In contrast to phosphonium ylides used in the Wittig reaction, phosphonate-stabilized carbanions are more nucleophilic but less basic. Likewise, phosphonate-stabilized carbanions can be alkylated. Unlike phosphonium ylides, the dialkylphosphate salt byproduct is easily removed by aqueous extraction. Several reviews have been published. Reaction mechanism The Horner–Wadsworth–Emmons reaction begins with the deprotonation of the phosphonate to give the phosphonate carbanion 1. Nucleophilic addition of the carbanion onto the aldehyde 2 (or ketone) producing 3a or 3b is the rate-limiting step. If ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxides
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 of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry. Many inorganic substances which bear the word ''hydroxide'' in their names are not ionic compounds of the hydroxide ion, but covalent compounds which contain hydroxy groups. Hydroxide ion The hydroxide ion is naturally produced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Ammonium Compounds
In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure , where R is an alkyl group, an aryl group or organyl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule. Quats are used in consumer applications including as antimicrobials (such as detergents and disinfectants), fabric softeners, and hair conditioners. As an antimicrobial, they are able to inactivate enveloped viruses (such as SARS-CoV-2). Quats tend to be gentler on surfaces than bleach-based disinfectants, and are generally fabric-safe. Synthesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reagents For Organic Chemistry
In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a substance ''consumed'' in the course of a chemical reaction. ''Solvents'', though involved in the reaction mechanism, are usually not called reactants. Similarly, ''catalysis, catalysts'' are not consumed by the reaction, so they are not reactants. In biochemistry, especially in connection with enzyme-catalyzed reactions, the reactants are commonly called substrate (biochemistry), substrates. Definitions Organic chemistry In organic chemistry, the term "reagent" denotes a chemical ingredient (a compound or mixture, typically of inorganic or small organic molecules) introduced to cause the desired transformation of an organic substance. Examples include the Collins reagent, Fenton's reagent, and Grignard reagents. Analytical chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
