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Benzylideneacetone
Benzylideneacetone is the organic compound described by the formula C6H5CH=CHC(O)CH3. Although both ''cis''- and ''trans''-isomers are possible for the α,β-unsaturated ketone, only the trans isomer is observed. Its original preparation demonstrated the scope of condensation reactions to construct new, complex organic compounds. Benzylideneacetone is used as a flavouring ingredient in food and perfumes. Preparation Benzylideneacetone can be efficiently prepared by the base-induced condensation of acetone and benzaldehyde: : However, the benzylideneacetone formed via this reaction can undergo another Claisen-Schmidt condensation with another molecule of benzaldehyde to form dibenzylideneacetone. Because relatively weak bases such as NaOH make very little of the enolate ion at equilibrium, there is still a lot of unreacted base left in the reaction mixture, which can go on and remove protons from the alpha carbon of benzylideneacetone, allowing it to undergo another Claisen- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dibenzylideneacetone
Dibenzylideneacetone or dibenzalacetone, often abbreviated dba, is an organic compound with the formula C17H14O. It is a pale-yellow solid insoluble in water, but soluble in ethanol. It was first prepared in 1881 by the German chemist Rainer Ludwig Claisen (1851–1930) and the Swiss chemist Charles-Claude-Alexandre Claparède (14 April 1858 – 1 November 1913). Preparation The ''trans'',''trans'' isomer can be prepared in high yield and purity by condensation of benzaldehyde and acetone with sodium hydroxide in a water/ethanol medium followed by recrystallization. : This reaction, which proceeds via the intermediacy of benzylideneacetone, is often performed in organic chemistry classes, and is called Claisen-Schmidt condensation. Reactions and derivatives Prolonged exposure to sunlight initiates +2cycloadditions, converting it to a mixture of dimeric and trimeric cyclobutane cycloadducts. Uses Dibenzylideneacetone is used as a component in sunscreens and as a ligand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dibenzylideneacetone
Dibenzylideneacetone or dibenzalacetone, often abbreviated dba, is an organic compound with the formula C17H14O. It is a pale-yellow solid insoluble in water, but soluble in ethanol. It was first prepared in 1881 by the German chemist Rainer Ludwig Claisen (1851–1930) and the Swiss chemist Charles-Claude-Alexandre Claparède (14 April 1858 – 1 November 1913). Preparation The ''trans'',''trans'' isomer can be prepared in high yield and purity by condensation of benzaldehyde and acetone with sodium hydroxide in a water/ethanol medium followed by recrystallization. : This reaction, which proceeds via the intermediacy of benzylideneacetone, is often performed in organic chemistry classes, and is called Claisen-Schmidt condensation. Reactions and derivatives Prolonged exposure to sunlight initiates +2cycloadditions, converting it to a mixture of dimeric and trimeric cyclobutane cycloadducts. Uses Dibenzylideneacetone is used as a component in sunscreens and as a ligand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(benzylidene)iron Tricarbonyl
(Benzylideneacetone)iron tricarbonyl is the organoiron compound with the formula (CHCH=CHC(O)CH)Fe(CO). It is a reagent for transferring the Fe(CO) unit. This red-colored compound is commonly abbreviated (bda)Fe(CO). Structure and bonding (bda)Fe(CO) is an example of a complex of an η-ketone. It is a piano stool complex. The compound is characterized by IR bands at 2065, 2005, and 1985 cm (cyclohexane solution), the three bands being indicative of the low symmetry of the complex, which is chiral. Synthesis, reactions, related reagents It is prepared by the reaction of Fe(CO) with benzylideneacetone. (bda)Fe(CO) sometimes reacts with Lewis bases to give adducts without displacement of the bda. The reagents of the type (bda)Fe(CO)(PR) function as sources of "Fe(CO)(PR)" (R = aryl, etc.). Other sources of Fe(CO) are Fe(CO) and Fe(CO)(cyclooctene). The latter is highly reactive and thermally sensitive. Imine derivatives of cinnamaldehyde, e.g. CHCH=CHC(H)=NCH, also form r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzylacetone
Benzylacetone (IUPAC name: 4-phenylbutan-2-one) is a liquid with a sweet, flowery smell that is considered to be the most abundant attractant compound in flowers (e.g. Coyote Tobacco, ''Nicotiana attenuata'') and one of volatile components of cocoa. It can be used as an attractant for melon flies ('' Bactrocera cucurbitae''), in perfume, and as an odorant for soap. It can be prepared by the hydrogenation of benzylideneacetone. See also * Odor * Pheromone * Fragrances An aroma compound, also known as an odorant, aroma, fragrance or flavoring, is a chemical compound that has a smell or odor. For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently vo ... References {{reflist External links Fluka 4-Phenyl-2-butanoneNIST 4-Phenyl-2-butanone Ketones Flavors Perfume ingredients Phenyl compounds Benzyl compounds Sweet-smelling chemicals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claisen-Schmidt Condensation
In organic chemistry, the Claisen–Schmidt condensation is the reaction between an aldehyde or ketone having an α-hydrogen with an aromatic carbonyl compound lacking an α-hydrogen. This reaction is named after two of its pioneering investigators Rainer Ludwig Claisen and J. G. Schmidt, who independently published on this topic in 1880 and 1881. An example is the synthesis of dibenzylideneacetone ((1''E'', 4''E'')-1,5-diphenylpenta-1,4-dien-3-one). : Quantitative yields in Claisen–Schmidt reactions have been reported in the absence of solvent using sodium hydroxide as the base and plus benzaldehydes Benzaldehyde (C6H5CHO) is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. It is a colorless liquid with a characteristic almond-like odor ....{{cite journal , doi = 10.3390/molecules17010571 , volume=17 , title=A Facile Solvent Free Claisen-Schmidt Reaction: Synthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LiHMDS EnolateFormation
Lithium bis(trimethylsilyl)amide is a lithiated organosilicon compound with the formula . It is commonly abbreviated as LiHMDS or Li(HMDS) (lithium hexamethyldisilazide - a reference to its conjugate acid Bis(trimethylsilyl)amine, HMDS) and is primarily used as a strong non-nucleophilic base and as a ligand. Like many lithium reagents, it has a tendency to aggregate and will form a Cyclic compound, cyclic Trimer (chemistry), trimer in the absence of coordinating species. Preparation LiHMDS is commercially available, but it can also be prepared by the deprotonation of bis(trimethylsilyl)amine with n-butyllithium, ''n''-butyllithium. This reaction can be performed In situ#Chemistry and chemical engineering, ''in situ''. : Once formed, the compound can be purified by Sublimation (phase transition), sublimation or distillation. Reactions and applications As a base LiHMDS is often used in organic chemistry as a strong non-nucleophilic base. Its conjugate acid has a Acid dissociatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warfarin
Warfarin, sold under the brand name Coumadin among others, is a medication that is used as an anticoagulant (blood thinner). It is commonly used to prevent blood clots such as deep vein thrombosis and pulmonary embolism, and to prevent stroke in people who have atrial fibrillation, valvular heart disease, or artificial heart valves. Less commonly, it is used following ST-segment elevation myocardial infarction and orthopedic surgery. It is generally taken by mouth, but may also be used intravenously. The common side effect is bleeding. Less common side effects may include areas of tissue damage and purple toes syndrome. Use is not recommended during pregnancy. The effects of warfarin typically should be monitored by checking prothrombin time (INR) every one to four weeks. Many other medications and dietary factors can interact with warfarin, either increasing or decreasing its effectiveness. The effects of warfarin may be reversed with phytomenadione (vitamin K1), fresh f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4-Hydroxycoumarin
4-Hydroxycoumarin is a coumarin derivative with a hydroxy group at the 4-position. Occurrence 4-Hydroxycoumarin is an important fungal metabolite from the precursor coumarin, and its production leads to further fermentative production of the natural anticoagulant dicoumarol. This happens in the presence of naturally occurring formaldehyde, which allows attachment of a second 4-hydroxycoumarin molecule through the linking carbon of the formaldehyde, to the 3-position of the first 4-hydroxycoumarin molecule, to give the semi-dimer the motif of the drug class. Dicoumarol appears as a fermentation product in spoiled sweet clover silages and is considered a mycotoxin. 4-Hydroxycoumarin is biosynthesized from malonyl-CoA and 2-hydroxybenzoyl-CoA by the enzyme 4-hydroxycoumarin synthase. Anticoagulants After the identification of dicoumarol and its anticoagulant activity, it became the prototype for a class of drugs. 4-Hydroxycoumarin forms the core of the chemical structure of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diiron Nonacarbonyl
Diiron nonacarbonyl is an organometallic compound with the formula Fe2(CO)9. This metal carbonyl is an important reagent in organometallic chemistry and of occasional use in organic synthesis. It is a more reactive source of Fe(0) than Fe(CO)5. This micaceous orange solid is virtually insoluble in all common solvents. Synthesis and structure Following the original method, photolysis of an acetic acid solution of Fe(CO)5 produces Fe2(CO)9 in good yield:King, R. B. Organometallic Syntheses. Volume 1 Transition-Metal Compounds; Academic Press: New York, 1965. . :2 Fe(CO)5 → Fe2(CO)9 + CO Fe2(CO)9 consists of a pair of Fe(CO)3 centers linked by three bridging CO ligands. Although older textbooks show an Fe-Fe bond consistent with the 18 electron rule (8 valence electrons from Fe, two each from the terminal carbonyls, one each from the bridging carbonyls and one from the other Fe atom in the metal-metal bond), theoretical analyses have consistently indicated the absence of a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazone
Hydrazones are a class of organic compounds with the structure . They are related to ketones and aldehydes by the replacement of the oxygen =O with the = functional group. They are formed usually by the action of hydrazine on ketones or aldehydes. Synthesis Hydrazine, organohydrazines, and 1,1-diorganohydrazines react with aldehydes and ketones to give hydrazones. : Phenylhydrazine reacts with reducing sugars to form hydrazones known as osazones, which was developed by German chemist Emil Fischer as a test to differentiate monosaccharides. Uses Hydrazones are the basis for various analyses of ketones and aldehydes. For example, dinitrophenylhydrazine coated onto a silica sorbent is the basis of an adsorption cartridge. The hydrazones are then eluted and analyzed by HPLC using a UV detector. The compound carbonyl cyanide-''p''-trifluoromethoxyphenylhydrazone (abbreviated as FCCP) is used to uncouple ATP synthesis and reduction of oxygen in oxidative phosphorylation in molecu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyran
In chemistry, pyran, or oxine, is a six-membered heterocyclic, non-aromatic ring, consisting of five carbon atoms and one oxygen atom and containing two double bonds. The molecular formula is C5H6O. There are two isomers of pyran that differ by the location of the double bonds. In 2''H''-pyran, the saturated carbon is at position 2, whereas, in 4''H''-pyran, the saturated carbon is at position 4. 4''H''-Pyran was first isolated and characterized in 1962 via pyrolysis of 2-acetoxy-3,4-dihydro-2''H''-pyran. It was found too unstable, particularly in the presence of air. 4''H''-pyran easily disproportionates to the corresponding dihydropyran and the pyrylium ion, which is easily hydrolyzed in aqueous medium. Although the pyrans themselves have little significance in chemistry, many of their derivatives are important biological molecules, such as the pyranoflavonoids. The term pyran is also often applied to the saturated ring analog, which is more properly referred to as tetrahydrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fe(CO)3-Crystals.jpg "Click for more on -> (benzylidene)iron Tricarbonyl")
