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Ketones, aliphatic aromatic

BTI is suitable for the direct hydroxylation of ketones. Aliphatic, aromatic and heterocyclic ketones in acetonitrile-water and trifluoroacetic acid afforded a-hydroxymethyl ketones (in the range of 70%), whereas a-methylene ketones, such as propiophenone, gave less satisfactory yields. [Pg.53]

Ketone, aliphatic, aromatic, naphtha, esters Water None... [Pg.1225]

Torlon-type polymers are unaffected by aliphatic, aromatic, chlorinated and fluorinated hydrocarbons, dilute acids, aldehydes, ketones, ethers and esters. Resistance to alkalis is poor. They have excellent resistance to radiation. If a total of 10 Mrad is absorbed at a radiation dosage of 1 Mrad/h the tensile strength decreases by only 5%. [Pg.524]

Good yields are usually obtained with aromatic aldehydes or ketones. Aliphatic aldehydes are poor substrates for the ordinary procedure, but react much better if the halo ester is first deprotonated with lithium diisopropylamide (LDA) in tetrahydrofuran at -78 °C, prior to addition of the aldehyde. [Pg.82]

An antipolymerization agent such as hydroquinone may be added to the reaction mixture to inhibit the polymerization of the maleate or fumarate compound under the reaction conditions. This reaction is preferably carried out at a temperature within the range of 20°C to 150°C. This reaction is preferably carried out at atmospheric pressure. Reaction time of 16 to 24 hours have bean specified for this reaction by J.T. Cassaday. The reaction is preferably carried out in a solvent such as the low molecular weight aliphatic monohydric alcohols, ketones, aliphatic esters, aromatic hydrocarbons or trialkyl phosphates. [Pg.894]

Aldehydes and ketones, both aromatic and aliphatic (including cyclic ketones), can be converted in high yields to dimeric alkenes by treatment with TiCl3 and a zinc-... [Pg.1561]

The catalytic system employing (2 - Fur)3P as ligand was applied to the coupling of methyl vinyl ketone and ethyl vinyl ketone to aromatic, aliphatic, acetylenic, and olefinic aldehydes (Scheme 23) [37]. Despite the hydrogenation conditions, alkyne and alkene moieties, as well as benzylic ether and nitro functional groups all remained intact. Furthermore, extremely high lev-... [Pg.127]

The solubility of most metals is much higher when they exist as organometallic complexes.4445 Naturally occurring chemicals that can partially complex with metal compounds and increase the solubility of the metal include aliphatic acids, aromatic acids, alcohols, aldehydes, ketones, amines, aromatic hydrocarbons, esters, ethers, and phenols. Several complexation processes, including chelation and hydration, can occur in the deep-well environment. [Pg.799]

LBADH also catalyzed the asymmetric reduction of a broad variety of differently substituted acetylenic ketones, including aromatic alkynones and a number of aliphatic derivatives [71]. For example, methyl alkynones bearing an aromatic unit attached to the triple bond were reduced to the corresponding (7 )-propargylic alcohols with >99% ee. Similarly, alkylsilyl-substituted... [Pg.151]

Metalated cyclic aldo-nitrones are characterized by high reactivity toward electrophilic reagents. Reactions with aldehydes and ketones afford satisfactory yields of a-hydroxymethyl substituted derivatives of nitrones (551). The reactions were also carried out with a number of aliphatic, aromatic, and hetero-aromatic aldehydes and ketones (Schemes 2.124 and 2.125). [Pg.230]

P.Y.l prints are comparatively sensitive to most common organic solvents, such as esters, ketones, and aromatic hydrocarbons, but completely fast to alcohols and aliphatic hydrocarbons. The prints are also resistant to soap, alkali, and acid. [Pg.222]

Abstract The basic principles of the oxidative carbonylation reaction together with its synthetic applications are reviewed. In the first section, an overview of oxidative carbonylation is presented, and the general mechanisms followed by different substrates (alkenes, dienes, allenes, alkynes, ketones, ketenes, aromatic hydrocarbons, aliphatic hydrocarbons, alcohols, phenols, amines) leading to a variety of carbonyl compounds are discussed. The second section is focused on processes catalyzed by Pdl2-based systems, and on their ability to promote different kind of oxidative carbonylations under mild conditions to afford important carbonyl derivatives with high selectivity and efficiency. In particular, the recent developments towards the one-step synthesis of new heterocyclic derivatives are described. [Pg.244]

Accordingly, ATH is a versatile method for the enantioselective reduction of prochiral aromatic ketones. Aliphatic unconjugated ketones, however, are only reduced in poor to moderate enantioselec-tivities up to date (33-36). [Pg.47]

REDUCTION WITH ALUMINUM AMALGAM Reduction of Aliphatic-Aromatic Ketones to Pinacols [144]... [Pg.212]

Conversion of Various Aliphatic, Aromatic and Cyclic Ketones. 83... [Pg.75]

Ketones, in contrast to aldehydes, occur frequently in plants. A phytochemical reduction of the keto group has been shown in aliphatic, aromatic s and cyclic ketones although it takes longer and is less complete than in the case of aldehydes. (For the theory of this transformation see Neuberg and Gorr. )... [Pg.83]

Crystalline polymers exhibit the following basic properties They are opaque as long as the size of the crystallites or spherulites, respectively, lies above the wavelength of light. Their solubility is restricted to few organic solvents at elevated temperature. The following crystalline polymers have attained technical importance as thermoplastic materials polyethylene, polypropylene, aliphatic polyamides, aliphatic/aromatic polyamides, aliphatic/aromatic polyesters, poly-oxymethylene, polytetrafluoroethylene, poly(phenylene sulfide), poly(arylene ether ketone)s. [Pg.28]

TEES is capable of treating several classes of organic compounds, including aliphatics, aromatics, chlorinated aliphatics and aromatics, polycyclic aromatics, cyanides, amines, phenolics, organic acids, and ketones. [Pg.844]

Variations on this theme include the use of acrolein/ammonia (72GEP2224160) and acrolein/acetaldehyde/ammonia (64BRP963887,69BRP1141526). Ketones can also be utilized. For example, 2,6-dimethylpyridine is obtained in 36% yield from combination of for-malin/acetone/ammonia (71GEP2064397) (Scheme 3). This general reaction has recently been extended to include the preparation of 2,6-disubstituted (78BEP858390) and 2,3-disubstituted (78GEP2712694) pyridines from aromatic or heteroaromatic ketones/aliphatic aldehydes and ammonia. [Pg.523]

Ethyl- or Dietbylcarbonate, (C2H50)2C0 mw 118.13, colorless liq with mild odor, sp gr 0.975 at 20°/4, fr p -43° bp 126.8° fl p 115°F (open cup) combustible but not inflammable insol in w miscible with ales, ketones, esters, aromatic hydrocarbons and some aliphatic sol ... [Pg.91]

R) -specific ADH from L. kefir was used for the reduction of various ketones to the corresponding secondary alcohols. Aliphatic, aromatic, and cyclic ketones as well as keto esters were accepted as substrates. The activities achieved with several substrates were compared with the activity obtained with the standard substrate of ADH, acetophenone (Fig. 2.2.4.4). As the figure shows, recombinant LK-ADH has a very broad substrate spectrum, including many types of ketones. [Pg.342]

An analogous non-electrochemical Ni(0)-catalysed process, exploited in a Mannich/ Reformatsky multicomponent process58, will be discussed in Section III (equation 41). In the third study, the a-bromoester Id is simply electrolysed in the presence of a carbonyl compound in DMF/THF in a 1 2 ratio using both indium and zinc rods as sacrificial anodes. While aldehydes afford the expected 3-hydroxyesters in high yield, aliphatic, aromatic and cyclic ketones, with the exception of acetone, directly afford /3-lactones,... [Pg.804]


See other pages where Ketones, aliphatic aromatic is mentioned: [Pg.444]    [Pg.155]    [Pg.444]    [Pg.155]    [Pg.231]    [Pg.561]    [Pg.13]    [Pg.177]    [Pg.238]    [Pg.296]    [Pg.225]    [Pg.1197]    [Pg.1212]    [Pg.561]    [Pg.152]    [Pg.117]    [Pg.334]    [Pg.124]    [Pg.34]   
See also in sourсe #XX -- [ Pg.254 ]




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Aliphatics ketones

Aliphatic—aromatic

Aromatic ketones

Ketones, aliphatic

Ketones, aliphatic-aromatic reduction

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