|
Dimedone
Dimedone is an organic compound with the formula . Classified as a cyclic diketone, it is a derivative of 1,3-Cyclohexanedione, 1,3-cyclohexanedione. It is a white solid that is soluble in water, as well as ethanol and methanol. It once was used as a reagent to test for the aldehyde functional group. Synthesis Dimedone is prepared from mesityl oxide and diethyl malonate via a Michael addition reaction. Chemical properties Tautomerism Dimedone is in equilibrium with its tautomer in solution — in a 2:1 keto to enol ratio in chloroform. Crystalline dimedone contains chains of molecules, in the enol form, linked by hydrogen bonds: Reaction with aldehydes Dimedone reacts with aldehydes to give crystalline derivatives, whose melting points can be used to distinguish between aldehydes. : References {{reflist Diketones 3-Hydroxypropenals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diketone
In organic chemistry, a dicarbonyl is a molecule containing two carbonyl () groups. Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls are in close enough proximity that their reactivity is changed, such as 1,2-, 1,3-, and 1,4-dicarbonyls. Their properties often differ from those of monocarbonyls, and so they are usually considered functional groups of their own. These compounds can have symmetrical or unsymmetrical substituents on each carbonyl, and may also be functionally symmetrical (dialdehydes, diketones, diesters, ''etc.'') or unsymmetrical (keto-esters, keto-acids, ''etc.''). 1,2-Dicarbonyls 1,2-Dialdehyde The only 1,2-dialdehyde is glyoxal, . Like many alkyldialdehydes, glyoxal is encountered almost exclusively as its hydrate and oligomers thereof. These derivatives often behave equivalently to the aldehydes since hydration is reversible. Glyoxal condenses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3-Cyclohexanedione
1,3-Cyclohexanedione is an organic compound with the formula (CH2)4(CO)2. It is one of three isomeric cyclohexanediones. It is a colorless compound that occurs naturally. It is the substrate for cyclohexanedione hydrolase. The compound exists mainly as the enol tautomer. Synthesis, structure, and reactivity 1,3-Cyclohexanedione is produced by semi-hydrogenation of resorcinol: :C6H4(OH)2 + H2 → C6H8O2 1,3-Cyclohexanedione exists in solution predominantly as the enol tautomer. : It reacts under acid catalysis with alcohols to 3-alkoxyenones. Its pKa is 5.26. Treatment of the sodium salt of the enolate with methyl iodide gives 2-methyl-1,3-cyclohexanedione, which also exists predominantly as the enol. Derivatives Dimedone (5,5-dimethyl-1,3-cyclohexanedione) is a well established reagent. Several herbicides against grasses are formal derivatives of 1,3-cyclohexanedione. Examples of commercial products include cycloxydim, clethodim, tralkoxydim, butroxydim, seth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesityl Oxide
Mesityl oxide is a Carbonyl#.CE.B1.2C.CE.B2-Unsaturated_carbonyl_compounds, α,β-unsaturated ketone with the formula CH3C(O)CH=C(CH3)2. This compound is a colorless, volatile liquid with a honey-like odor. Synthesis It is prepared by the aldol condensation of acetone to give diacetone alcohol, which readily dehydrates to give this compound. : Phorone and isophorone may be formed under the same conditions. Isophorone originates via a Michael addition: : Phorone is formed by continued aldol condensation: : Uses Mesityl oxide is used as a solvent and in the production of methyl isobutyl ketone by hydrogenation: : Further hydrogenation gives 4-methyl-2-pentanol (methyl isobutyl carbinol). Dimedone is another established use of mesityl oxide. References {{reflist External linksIPCS INCHEM Description Enones Ketone solvents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Addition Reaction
In organic chemistry, the Michael reaction or Michael 1,4 addition is a reaction between a Michael donor (an enolate or other nucleophile) and a Michael acceptor (usually an α,β-unsaturated carbonyl) to produce a Michael adduct by creating a carbon-carbon bond at the acceptor's β-carbon. It belongs to the larger class of conjugate additions and is widely used for the mild formation of carbon–carbon bonds. The Michael addition is an important atom-economical method for diastereoselective and enantioselective C–C bond formation, and many asymmetric variants exist : In this general Michael addition scheme, either or both of R and R' on the nucleophile (the Michael donor) represent electron-withdrawing substituents such as acyl, cyano, nitro, or sulfone groups, which make the adjacent methylene hydrogen acidic enough to form a carbanion when reacted with the base, ''B:''. For the alkene (the Michael acceptor), the R" substituent is usually a carbonyl, which makes the compo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diketones
In organic chemistry, a dicarbonyl is a molecule containing two carbonyl () Functional group, groups. Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls are in close enough proximity that their Reactivity (chemistry), reactivity is changed, such as 1,2-, 1,3-, and 1,4-dicarbonyls. Their properties often differ from those of monocarbonyls, and so they are usually considered functional groups of their own. These compounds can have symmetrical or unsymmetrical substituents on each carbonyl, and may also be functionally symmetrical (dialdehydes, diketones, diesters, ''etc.'') or unsymmetrical (keto-esters, keto-acids, ''etc.''). 1,2-Dicarbonyls 1,2-Dialdehyde The only 1,2-dialdehyde is glyoxal, . Like many alkyldialdehydes, glyoxal is encountered almost exclusively as its hydrate and oligomers thereof. These derivatives often behave equivalently to the aldehydes since hydra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the pseudoelement symbol for ethyl group, ethyl. Ethanol is a Volatility (chemistry), volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. As a psychoactive depressant, it is the active ingredient in alcoholic beverages, and the second most consumed drug globally behind caffeine. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. Historically it was used as a general anesthetic, and has modern medical applications as an antiseptic, disinfectant, solvent for some medications, and antidote for methanol poisoning and ethylene glycol poisoning. It is used as a chemical solvent and in the Chemical synthesis, synthesis of orga ... [...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] |
Aldehyde
In organic chemistry, an aldehyde () (lat. ''al''cohol ''dehyd''rogenatum, dehydrogenated alcohol) 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 a common motif in many chemicals important in technology and biology. Structure and bonding Aldehyde molecules have a central carbon atom that is connected by a double bond to oxygen, a single bond to hydrogen and another 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 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 such as formaldehyde and acetaldehyde are solubl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Group
In organic chemistry, a functional group is any substituent or moiety (chemistry), moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition. This enables systematic prediction of chemical reactions and behavior of chemical compounds and the design of chemical synthesis. The Reactivity (chemistry), reactivity of a functional group can be modified by other functional groups nearby. Functional group interconversion can be used in retrosynthetic analysis to plan organic synthesis. A functional group is a group of atoms in a molecule with distinctive Chemical property, chemical properties, regardless of the other atoms in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by covalent bonds. For repeating units of polymers, functional groups attach to their Chemical polarity, nonp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Malonate
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. Structure and properties Malonic acid is a rather simple dicarboxylic acid, with two carboxyl groups close together. In forming diethyl malonate from malonic acid, the hydroxyl group (−OH) on both of the carboxyl groups is replaced by an ethoxy group (−OEt; −OCH2CH3). The methylene group (−CH2−) in the middle of the malonic part of the diethyl malonate molecule is neighboured by two carbonyl groups (−C(=O)−). The hydrogen atoms on the carbon adjacent to the carbonyl group in a molecule are significantly more acidic than hydrogen atoms on a carbon adjacent to alkyl groups (up to 30 orders of magnitude). (This is known as the α position wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
In chemistry, tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is a quantum superposition, essentially the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroform
Chloroform, or trichloromethane (often abbreviated as TCM), is an organochloride with the formula and a common solvent. It is a volatile, colorless, sweet-smelling, dense liquid produced on a large scale as a precursor to refrigerants and polytetrafluoroethylene (PTFE). Chloroform was once used as an inhalational anesthetic between the 19th century and the first half of the 20th century. It is miscible with many solvents but it is only very slightly soluble in water (only 8 g/L at 20°C). Structure and name The molecule adopts a tetrahedral molecular geometry with C3v symmetry. The chloroform molecule can be viewed as a methane molecule with three hydrogen atoms replaced with three chlorine atoms, leaving a single hydrogen atom. The name "chloroform" is a portmanteau of ''terchloride'' (tertiary chloride, a trichloride) and ''formyle'', an obsolete name for the methylylidene radical (CH) derived from formic acid. Natural occurrence Many kinds of seaweed produce chlor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
