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2-methylbutyric Acid
2-Methylbutanoic acid, also known as 2-methylbutyric acid is a branched-chain alkyl carboxylic acid with the chemical formula CH3CH2CH(CH3)CO2H, classified as a short-chain fatty acid. It exists in two enantiomeric forms, (''R'')- and (''S'')-2-methylbutanoic acid. (''R'')-2-methylbutanoic acid occurs naturally in cocoa beans and (''S'')-2-methylbutanoic occurs in many fruits such as apples and apricots, as well as in the scent of the orchid ''Luisia, Luisia curtisii''. History 2-Methylbutanoic acid is a minor constituent of ''Angelica archangelica'' and the perennial flowering plant Valerian (herb), valerian (''Valeriana officinalis''), where it co-occurs with valeric acid and isovaleric acid. The dried root of this plant has been used medicinally since antiquity. The chemical identity of all three compounds was first investigated in the 19th century by oxidation of the components of fusel alcohol, which includes the five-carbon amyl alcohols. Among the products isolated was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyl
In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cycloalkane by removal of a hydrogen atom from a Ring (chemistry), ring and has the general formula . Typically an alkyl is a part of a larger molecule. In structural formulae, the symbol R is used to designate a generic (unspecified) alkyl group. The smallest alkyl group is methyl, with the formula . Related concepts Alkylation is the addition of alkyl groups to molecules, often by alkylating agents such as Haloalkane, alkyl halides. Alkylating antineoplastic agents are a class of compounds that are used to treat cancer. In such case, the term alkyl is used loosely. For example, nitrogen mustards are well-known alkylating agents, but they are not simple hydrocarbons. In chemistry, alkyl is a group, a substituent, that is attached to ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grignard Reaction
The Grignard reaction () is an organometallic chemical reaction in which, according to the classical definition, carbon alkyl, allyl, vinyl, or aryl magnesium halides (Grignard reagent) are added to the carbonyl groups of either an aldehyde or ketone under anhydrous conditions. This reaction is important for the formation of carbon–carbon bonds. History and definitions Grignard reactions and reagents were discovered by and are named after the French chemist François Auguste Victor Grignard (University of Nancy, France), who described them in 1900. He was awarded the 1912 Nobel Prize in Chemistry for this work. The reaction of an organic halide with magnesium is ''not'' a Grignard reaction, but provides a Grignard reagent.IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). . . Classically, the Grignard reaction refers to the reaction between a ketone or aldeh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-Methylbutanoic Acid
Isovaleric acid, also known as 3-methylbutanoic acid or β-methylbutyric acid, is a branched-chain alkyl carboxylic acid with the chemical formula (CH3)2CHCH2CO2H. It is classified as a short-chain fatty acid. Like other low-molecular-weight carboxylic acids, it has an unpleasant odor. The compound occurs naturally and can be found in many foods, such as cheese, soy milk, and apple juice. History 3-Methylbutanoic acid is a minor constituent of the perennial flowering plant valerian ('' Valeriana officinalis''), from which it got its trivial name isovaleric acid: an isomer of valeric acid which shares its unpleasant odor. The dried root of this plant has been used medicinally since antiquity. Their chemical identity was first investigated in the 19th century by oxidation of the components of fusel alcohol, which includes the five-carbon amyl alcohols. Manufacture In industry, 3-methylbutanoic acid is produced by the hydroformylation of isobutylene with syngas, forming is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odor
An odor (American English) or odour ( Commonwealth English; see spelling differences) is a smell or a scent caused by one or more volatilized chemical compounds generally found in low concentrations that humans and many animals can perceive via their olfactory system. While ''smell'' can refer to pleasant and unpleasant odors, the terms ''scent'', ''aroma'', and ''fragrance'' are usually reserved for pleasant-smelling odors and are frequently used in the food and cosmetic industry to describe floral scents or to refer to perfumes. Odor physiology Sense of smell The perception of odors, or sense of smell, is mediated by the olfactory nerve. The olfactory receptor (OR) cells are neurons present in the olfactory epithelium, which is a small patch of tissue at the back of the nasal cavity. There are millions of olfactory receptor neurons that act as sensory signaling cells. Each neuron has cilia in direct contact with the air. Odorous molecules bind to receptor pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl Chloride
In organic chemistry, an acyl chloride (or acid chloride) is an organic compound with the functional group . Their formula is usually written , where R is a side chain. They are reactive derivatives of carboxylic acids (). A specific example of an acyl chloride is acetyl chloride, . Acyl chlorides are the most important subset of acyl halides. Nomenclature Where the acyl chloride moiety takes priority, acyl chlorides are named by taking the name of the parent carboxylic acid, and substituting ''-yl chloride'' for ''-ic acid''. Thus: : : : butyr''ic acid'' (C3H7COOH) → butyr''yl chloride'' (C3H7COCl) (Idiosyncratically, for some trivial names, ''-oyl chloride'' substitutes ''-ic acid''. For example, pival''ic acid'' becomes pival''oyl chloride'' and acryl''ic acid'' becomes acryl''oyl chloride.'' The names pivalyl chloride and acrylyl chloride are less commonly used, although they are arguably more logical.) When other functional groups take priority, acyl chlorides a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid Anhydride
An acid anhydride is a type of chemical compound derived by the removal of water molecules from an acid. In organic chemistry, organic acid anhydrides contain the functional group . Organic acid anhydrides often form when one equivalent of water is removed from two equivalents of an organic acid in a dehydration reaction. In inorganic chemistry, an acid anhydride refers to an acidic oxide, an oxide that reacts with water to form an oxyacid (an inorganic acid that contains oxygen or carbonic acid), or with a base to form a salt. See also * Base anhydride, an oxide that reacts with water to form a hydroxide 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 ... salt References {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Lactones are cyclic carboxylic esters; naturally occurring lactones are mainly 5- and 6-membered ring lactones. Lactones contribute to the aroma of fruits, butter, cheese, vegetables like celery and other foods. Esters can be formed from oxoacids (e.g. esters of acetic acid, carbonic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amide
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a chemical compound, compound with the general formula , where R, R', and R″ represent any group, typically organyl functional group, groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the Polymer backbone, main chain of a protein, and an isopeptide bond when it occurs in a side chain, as in asparagine and glutamine. It can be viewed as a Derivative (chemistry), derivative of a carboxylic acid () with the hydroxyl group () replaced by an amino group (); or, equivalently, an acyl group, acyl (alkanoyl) group () joined to an amino group. Common amides are formamide (), acetamide (), benzamide (), and dimethylformamide (). Some uncommon examples of amides are ''N''-chloroacetamide () and chloroformamide (). Amides are qualified as primary (chemistry), primary, secondary (chemistry), secondary, and tertiary (chemistry), tertiary according to the number of acyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BINAP
BINAP (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) is an organophosphorus compound. This Optical isomerism, chiral diphosphines, diphosphine ligand is widely used in chiral synthesis, asymmetric synthesis. It consists of a pair of 2-diphenylphosphinonaphthalene, naphthyl groups linked at the 1 and 1′ positions. This C2-Symmetric ligands, C2-symmetric framework lacks a stereocenter, stereogenic atom, but has axial chirality due to restricted rotation (atropisomerism). The barrier to racemization is high due to steric hindrance, which limits rotation about the bond linking the naphthyl rings. The dihedral angle between the naphthyl groups is approximately 90°. The natural bite angle is 93°. Use as ligand in asymmetric catalysis BINAP is used in organic synthesis for enantioselective transformations catalyzed by its complex (chemistry), complexes of ruthenium, rhodium, and palladium. As pioneered by Ryōji Noyori and his co-workers, rhodium complexes of BINAP are usefu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruthenium
Ruthenium is a chemical element; it has symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is unreactive to most chemicals. Karl Ernst Claus, a Russian scientist of Baltic-German ancestry, discovered the element in 1844 at Kazan State University and named it in honor of Russia. (He used the Latin name '' Ruthenia'', which can have other meanings, but specifically stated that the element was named in honor of his "motherland".) Ruthenium is usually found as a minor component of platinum ores; the annual production has risen from about 19 tonnes in 2009 to some 35.5 tonnes in 2017. Most ruthenium produced is used in wear-resistant electrical contacts and thick-film resistors. A minor application for ruthenium is in platinum alloys and as a chemical catalyst. A new application of ruthenium is as the capping layer for extreme ultraviolet photoma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiglic Acid
Tiglic acid is a monocarboxylic unsaturated organic acid. It is found in croton oil and in several other natural products. It has also been also isolated from the defensive secretion of certain beetles. Properties and uses Tiglic acid has a double bond between the second and third carbons of the chain. Tiglic acid and angelic acid form a pair of ''Geometric isomerism#Cis vs trans physical properties, cis-trans'' isomers. Tiglic acid is a volatile and crystallizable substance with a sweet, warm, spicy odour. It is used in making perfumes and flavoring agents. The salts and esters of tiglic acid are called tiglates. Toxicity Tiglic acid is a skin and eye irritant. The inhalation of the substance causes respiratory tract irritation. It is listed on the Toxic Substances Control Act (TSCA). Names and discovery In 1819 Pelletier and Caventou isolated a peculiar volatile and crystallizable acid from the seeds of ''Schoenocaulon officinalis'', a Mexican plant of family Melanthaceae (also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asymmetric Hydrogenation
Asymmetric hydrogenation is a chemical reaction that adds two atoms of hydrogen to a target (substrate) molecule with three-dimensional spatial selectivity. Critically, this selectivity does not come from the target molecule itself, but from other reagents or catalysts present in the reaction. This allows spatial information (what chemists refer to as chirality) to transfer from one molecule to the target, forming the product as a single enantiomer. The chiral information is most commonly contained in a catalyst and, in this case, the information in a single molecule of catalyst may be transferred to many substrate molecules, amplifying the amount of chiral information present. Similar processes occur in nature, where a chiral molecule like an enzyme can catalyse the introduction of a chiral centre to give a product as a single enantiomer, such as amino acids, that a cell needs to function. By imitating this process, chemists can generate many novel synthetic molecules that inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
