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2-propenal
Acrolein (systematic name: propenal) is the simplest unsaturated aldehyde. It is a colorless liquid with a piercing, acrid smell. The smell of burnt fat (as when cooking oil is heated to its smoke point) is caused by glycerol in the burning fat breaking down into acrolein. It is produced industrially from propylene and mainly used as a biocide and a building block to other chemical compounds, such as the amino acid methionine. History Acrolein was first named and characterized as an aldehyde by the Swedish chemist Jöns Jacob Berzelius in 1839. He had been working with it as a thermal degradation product of glycerol, a material used in the manufacture of soap. The name is a contraction of ‘acrid’ (referring to its pungent smell) and ‘oleum’ (referring to its oil-like consistency). In the 20th century, acrolein became an important intermediate for the industrial production of acrylic acid and acrylic plastics. Production Acrolein is prepared industrially by oxidation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotonaldehyde
Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the ''E''- and ''Z''-isomers, which differ with respect to the relative position of the methyl and formyl groups. The ''E''-isomer is more common (data given in Table is for the ''E''-isomer). This lachrymatory liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in organic synthesis. It occurs in a variety of foodstuffs, e.g. soybean oils. Production and reactivity Crotonaldehyde is produced by the aldol condensation of acetaldehyde: :2 CH3CHO → CH3CH=CHCHO + H2O Crotonaldehyde is a multifunctional molecule that exhibits diverse reactivity. It is a prochiral dienophile. It is a Michael acceptor. Addition of methylmagnesium chloride produces 3-penten-2-ol. Polyurethane catalyst ''N'',''N'',''N''′,''N''′-tetramethyl-1,4-butanediamine (also known as NIAX TM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrochemical
Petrochemicals (sometimes abbreviated as petchems) are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as maize, palm fruit or sugar cane. The two most common petrochemical classes are olefins (including ethylene and propylene) and aromatics (including benzene, toluene and xylene isomers). Oil refineries produce olefins and aromatics by fluid catalytic cracking of petroleum fractions. Chemical plants produce olefins by steam cracking of natural gas liquids like ethane and propane. Aromatics are produced by catalytic reforming of naphtha. Olefins and aromatics are the building-blocks for a wide range of materials such as solvents, detergents, and adhesives. Olefins are the basis for polymers and oligomers used in plastics, resins, fibers, elastomers, lubricants, and gels. Global ethylene production was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3,4-Epoxycyclohexylmethyl-3’,4’-epoxycyclohexane Carboxylate
3,4-Epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate (ECC) is a cycloaliphatic epoxy resin which is used in many industrial applications. It reacts by cationic polymerization using thermolatent photoinitiators to form crosslinked insoluble thermosets. Formulations based on cycloaliphatic epoxy resins such as ECC are known to form by curing thermosets with high heat and chemical resistance and good adhesion. History The homopolymerization of ECC is based on radiation curing, which proceeds via a photochemical formation of a super acid and subsequent cationic polymerization. This was the first time realized in the 1970s. Fabrication ECC can be prepared via Tishchenko reaction of tetrahydrobenzaldehyde and subsequent epoxidation with a peracid. Properties ECC has a dynamic viscosity of 400 mPa·s at 25 °C. Reactivity For homopolymerization of ECC 1.5 to 3 wt. % of an initiator are added. Above 3 wt% initiator no further acceleration was found, increasing pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrac Aldehyde
Hydroxymethylpentylcyclohexenecarboxaldehyde is a synthetic fragrance known by the trade names Lyral, Kovanol, Mugonal, Landolal. It is found in some soaps, eau de toilettes, aftershaves and deodorants. Synthesis Typical synthesis starts from myrcene and involves a Diels–Alder reaction with acrolein to produce the cyclohexenecarbaldehyde group, this species is marketed as a fragrance in its own right, most commonly under the name 'myrac aldehyde'. Acid-catalyzed hydration of this completes the synthesis by forming the tertiary alcohol. Safety Lyral is known to act as a skin allergen and is listed as such in EU Directive 76/768/EEC. It is commonly tested for in patients undergoing patch testing. References {{Reflist Perfume ingredients Aldehydes Tertiary alcohols Cyclohexenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norbornene
Norbornene or norbornylene or norcamphene is a highly strained bridged cyclic hydrocarbon. It is a white solid with a pungent sour odor. The molecule consists of a cyclohexene ring with a methylene bridge between carbons 1 and 4. The molecule carries a double bond which induces significant ring strain and significant reactivity. Production Norbornene is made by a Diels–Alder reaction of cyclopentadiene and ethylene. Many substituted norbornenes can be prepared similarly. Related bicyclic compounds are norbornadiene, which has the same carbon skeleton but with two double bonds, and norbornane which is prepared by hydrogenation of norbornene. Reactions Norbornene undergoes an acid-catalyzed hydration reaction to form norborneol. This reaction was of great interest in the elucidation of the non-classical carbonion controversy. Norbornene is used in the Catellani reaction and in norbornene-mediated ''meta''-C−H activation. Certain substituted norbornenes undergo unus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxymethylpentylcyclohexenecarboxaldehyde
Hydroxymethylpentylcyclohexenecarboxaldehyde is a synthetic fragrance known by the trade names Lyral, Kovanol, Mugonal, Landolal. It is found in some soaps, eau de toilettes, aftershaves and deodorants. Synthesis Typical synthesis starts from myrcene and involves a Diels–Alder reaction with acrolein Acrolein (systematic name: propenal) is the simplest unsaturated aldehyde. It is a colorless liquid with a piercing, acrid smell. The smell of burnt fat (as when cooking oil is heated to its smoke point) is caused by glycerol in the burning fa ... to produce the cyclohexenecarbaldehyde group, this species is marketed as a fragrance in its own right, most commonly under the name 'myrac aldehyde'. Acid-catalyzed hydration of this completes the synthesis by forming the tertiary alcohol. Safety Lyral is known to act as a skin allergen and is listed as such in EU Directive 76/768/EEC. It is commonly tested for in patients undergoing patch testing. References {{Reflist Perfume i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentaerythritol
Pentaerythritol is an organic compound with the formula C(CH2OH)4. Classified as a polyol, it is a white solid. Pentaerythritol is a building block for the synthesis and production of explosives, plastics, paints, appliances, cosmetics, and many other commercial products. The word pentaerythritol is a blend of ''penta-'' in reference to its 5 carbon atoms and ''erythritol'', which also possesses 4 alcohol groups. Synthesis Pentaerythritol was first reported in 1891 by German chemist Bernhard Tollens and his student P. Wigand. It may be prepared via a base-catalyzed multiple- addition reaction between acetaldehyde and 3 equivalents of formaldehyde to give pentaerythrose (CAS: 3818-32-4), followed by a Cannizzaro reaction with a fourth equivalent of formaldehyde to give the final product. Uses Pentaerythritol is a versatile building block for the preparation of many compounds, particularly polyfunctionalized derivatives. applications include alkyd resins, varnishes, polyv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirocycle
In organic chemistry, spiro compounds are compounds that have at least two molecular rings with only one common atom. The simplest spiro compounds are bicyclic (having just two rings), or have a bicyclic portion as part of the larger ring system, in either case with the two rings connected through the defining single common atom. The one common atom connecting the participating rings distinguishes spiro compounds from other bicyclics: from ''isolated ring compounds'' like biphenyl that have no connecting atoms, from ''fused ring compounds'' like decalin having two rings linked by two adjacent atoms, and from ''bridged ring compounds'' like norbornane with two rings linked by two non-adjacent atoms.For all four categories, see The specific chapters can be found aan respectively, same access date. For the description featuring adjacent atoms for all but the isolated category, see Clayden, op. cit. Spiro compounds may be fully carbocyclic (all carbon) or heterocyclic (hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetal
In organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. The two R' groups can be equivalent to each other (a "symmetric acetal") or not (a "mixed acetal"). Acetals are formed from and convertible to aldehydes or ketones and have the same oxidation state at the central carbon, but have substantially different chemical stability and reactivity as compared to the analogous carbonyl compounds. The central carbon atom has four bonds to it, and is therefore saturated and has tetrahedral geometry. The term ketal is sometimes used to identify structures associated with ketones (both R groups organic fragments rather than hydrogen) rather than aldehydes and, historically, the term acetal was used specifically for the aldehyde-related cases (having at least one hydrogen in place o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Acceptor
In organic chemistry, the Michael reaction or Michael 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophile
In chemistry, an electrophile is a chemical species that forms bonds with nucleophiles by accepting an electron pair. Because electrophiles accept electrons, they are Lewis acids. Most electrophiles are positively charged, have an atom that carries a partial positive charge, or have an atom that does not have an octet of electrons. Electrophiles mainly interact with nucleophiles through addition and substitution reactions. Frequently seen electrophiles in organic syntheses include cations such as H+ and NO+, polarized neutral molecules such as HCl, alkyl halides, acyl halides, and carbonyl compounds, polarizable neutral molecules such as Cl2 and Br2, oxidizing agents such as organic peracids, chemical species that do not satisfy the octet rule such as carbenes and radicals, and some Lewis acids such as BH3 and DIBAL. Organic chemistry Addition of halogens These occur between alkenes and electrophiles, often halogens as in halogen addition reactions. Comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
