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Sodium Trichloroacetate
Sodium trichloroacetate is a chemical compound with a formula of CCl3CO2Na. It is used to increase sensitivity and precision during transcript mapping. It was previously used as an herbicide starting in the 1950s but regulators removed it from the market in the late 1980s and early 1990s. Preparation Sodium trichloroacetate is made by reaction trichloroacetic acid with sodium hydroxide: :CCl3CO2H + NaOH -> CCl3CO2Na + H2O Reactions Basicity Sodium trichloroacetate is a weaker base than sodium acetate because of the electron-withdrawing nature of the trichloromethyl group. Sodium trifluoroacetate is likewise a weaker base. However, it can easily be protonated in the presence of suitably strong acids: :CCl3CO2- + H2SO4 -> CCl3CO2H + HSO4- Trichloromethyl-anion precursor This reagent is useful for introducing the trichloromethyl group into other molecules. Decarboxylation produces the trichloromethyl anion, which is a sufficiently strong nucleophile to attack various ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, volatile, colourless, flammable liquid with a distinctive alcoholic odour similar to that of ethanol (potable alcohol). A polar solvent, methanol acquired the name wood alcohol because it was once produced chiefly by the 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 to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl benzoate, anisole, peroxyacids, as well as a host of more specialised chemicals. Occurrence Small amounts of methanol are present in normal, healthy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Acetate
Sodium acetate, CH3COONa, also abbreviated Na O Ac, is the sodium salt of acetic acid. This colorless deliquescent salt has a wide range of uses. Applications Biotechnological Sodium acetate is used as the carbon source for culturing bacteria. Sodium acetate is also useful for increasing yields of DNA isolation by ethanol precipitation. Industrial Sodium acetate is used in the textile industry to neutralize sulfuric acid waste streams and also as a photoresist while using aniline dyes. It is also a pickling agent in chrome tanning and helps to impede vulcanization of chloroprene in synthetic rubber production. In processing cotton for disposable cotton pads, sodium acetate is used to eliminate the buildup of static electricity. Concrete longevity Sodium acetate is used to mitigate water damage to concrete by acting as a concrete sealant, while also being environmentally benign and cheaper than the commonly used epoxy alternative for sealing concrete against water permeation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl Halide
In organic chemistry, an acyl halide (also known as an acid halide) is a chemical compound derived from an oxoacid by replacing a hydroxyl group () with a halide group (, where X is a halogen). If the acid is a carboxylic acid (), the compound contains a functional group, which consists of a carbonyl group () singly bonded to a halogen atom. The general formula for such an acyl halide can be written RCOX, where R may be, for example, an alkyl group, CO is the carbonyl group, and X represents the halide, such as chloride. Acyl chlorides are the most commonly encountered acyl halides, but acetyl iodide is the one produced (transiently) on the largest scale. Billions of kilograms are generated annually in the production of acetic acid. Preparation Aliphatic acyl halides On an industrial scale, the reaction of acetic anhydride with hydrogen chloride produces a mixture of acetyl chloride and acetic acid: :(CH3CO)2O + HCl -> CH3COCl + CH3CO2H Common syntheses of acyl chlori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jocic–Reeve Reaction
In organic chemistry, the Jocic reaction, also called the Jocic–Reeve reaction (named after Zivojin Jocic and Wilkins Reeve) is a name reaction that generates α-substituted carboxylic acids from trichloromethylcarbinols and corresponding nucleophiles in the presence of sodium hydroxide. The reaction involves nucleophilic displacement of the hydroxyl group in a 1,1,1-trichloro-2-hydroxyalkyl structure with concomitant conversion of the trichloromethyl portion to a carboxylic acid or similar functional group. Mechanism The reaction mechanism involves an epoxide intermediate that undergoes an SN2 reaction by the nucleophile. As a result of this mechanistic aspect, the reaction can easily occur on secondary or tertiary positions, and chiral products can be made by using chiral alcohol substrates. The reaction is one stage of the Corey–Link reaction, the Bargellini reaction, and other processes for synthesizing α-amino acids and related structures. Using hydride as the nucleo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considered re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Acid Anhydride
An organic acid anhydride is an acid anhydride that is an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word ''acid'' in the name of the parent carboxylic acid by the word ''anhydride''. Thus, (CH3CO)2O is called ''acetic anhydride.'' Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known, whereby reaction occurs between two different carboxylic acids. Nomenclature of unsymmetrical acid anhydrides list the names of both of the reacted carboxylic acids before the word "anhydride" (for example, the dehydration reaction between benzoic acid and propanoic acid would yield "benzoic propanoic anhydride"). One or both acyl groups of an acid anhydride may also be d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldehyde
In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are common and play important roles in the technology and biological spheres. Structure and bonding Aldehydes feature a carbon center that is connected by a double bond to oxygen and a single bond to hydrogen and single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen. The central carbon is often described as being sp2- hybridized. The aldehyde group is somewhat polar. The C=O bond length is about 120-122 picometers. Physical properties and characterization Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes are more soluble in water, formaldehyde and acetaldehyde completely so. The volatile aldehydes have pungent odors. Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e.g. nickel carbonyl). The remainder of this article concerns itself with the organic chemistry definition of carbonyl, where carbon and oxygen share a double bond. Carbonyl compounds In organic chemistry, a carbonyl group characterizes the following types of compounds: Other organic carbonyls are urea and the carbamates, the derivatives of acyl chlorides chloroformates and phosgene, carbonate esters, thioesters, lactones, lactams, hydroxamates, and isocyanates. Examples of inorganic carbonyl compounds are carbon dioxide and carbonyl su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleophile
In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are Lewis bases. ''Nucleophilic'' describes the affinity of a nucleophile to bond with positively charged atomic nuclei. Nucleophilicity, sometimes referred to as nucleophile strength, refers to a substance's nucleophilic character and is often used to compare the affinity of atoms. Neutral nucleophilic reactions with solvents such as alcohols and water are named solvolysis. Nucleophiles may take part in nucleophilic substitution, whereby a nucleophile becomes attracted to a full or partial positive charge, and nucleophilic addition. Nucleophilicity is closely related to basicity. History The terms ''nucleophile'' and '' electrophile'' were introduced by Christopher Kelk Ingold in 1933, replacing the terms ''anionoid'' and ''catio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichloromethyl Group
The trichloromethyl group is a functional group that has the formula –CCl3. The naming of is group is derived from the methyl group (which has the formula –CH3), by replacing each hydrogen atom by a chlorine atom. Compounds with this group are a subclass of the organochlorines. Some notable examples of compounds with this group are trichloromethane H–, 1,1,1-trichloroethane –, and chloral –. The trichloromethyl group has a significant electronegativity. For this reason, trichloromethyl-substituted acids, such as trichloromethanesulfonic acid, are often stronger than the original. For example, the acidity constant (pKa) of trichloroacetic acid – is 0.77, whereas that of acetic acid is 4.76. By the same principle, the trichloromethyl group generally lowers the basicity of organic compounds, e.g. trichloroethanol. See also * Trifluoromethyl group The trifluoromethyl group is a functional group that has the formula -CF3. The naming of is group is derived from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbicide
Herbicides (, ), also commonly known as weedkillers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page for EPA reports on pesticide use ihere Selective herbicides control specific weed species, while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called total weedkillers in commercial products) can be used to clear waste ground, industrial and construction sites, railways and railway embankments as they kill all plant material with which they come into contact. Apart from selective/non-selective, other important distinctions include ''persistence'' (also known as ''residual action'': how long the product stays in place and remains active), ''means of uptake'' (whether it is absorbed by above-ground foliage only, through the roots, or by other means), and ''mechanism of action'' (how it works). Historic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the synthesis of organic compounds, and as a fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world production of ethanol was , coming mostly from Brazil and the U.S. Etymology ''Ethanol'' is the systematic name defined by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
