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4- butane reaction with

These systems are common in liquid extraction and also in a multiphase reactor with an organic and an aqueous phase. Common sources of pollution are incomplete separation and contamination due to trace organics in the aqueous phase. An example is in alkylation reactions (e.g., n-butane reaction with olefins to form isooctanes). Strong acids, such as sulfuric and hydrofluoric acids, are used as catalysts, and the recovery and the recycle of acid need to be optimized in order to reduce the waste generation. [Pg.225]

Product distribution from ketene and diazomethane 778 photolysis in the presence of 2,3-dimethyl-2,3-epoxy-butane. Reaction with CH2(d A,)... [Pg.134]

When a reactant is chiral but optically inactive because it is racemic any products derived from its reactions with optically inactive reagents will be optically inactive For example 2 butanol is chiral and may be converted with hydrogen bromide to 2 bromo butane which is also chiral If racemic 2 butanol is used each enantiomer will react at the same rate with the achiral reagent Whatever happens to (/ ) (—) 2 butanol is mir rored m a corresponding reaction of (5) (+) 2 butanol and a racemic optically inactive product results... [Pg.299]

Fresh butane mixed with recycled gas encounters freshly oxidized catalyst at the bottom of the transport-bed reactor and is oxidized to maleic anhydride and CO during its passage up the reactor. Catalyst densities (80 160 kg/m ) in the transport-bed reactor are substantially lower than the catalyst density in a typical fluidized-bed reactor (480 640 kg/m ) (109). The gas flow pattern in the riser is nearly plug flow which avoids the negative effect of backmixing on reaction selectivity. Reduced catalyst is separated from the reaction products by cyclones and is further stripped of products and reactants in a separate stripping vessel. The reduced catalyst is reoxidized in a separate fluidized-bed oxidizer where the exothermic heat of reaction is removed by steam cods. The rate of reoxidation of the VPO catalyst is slower than the rate of oxidation of butane, and consequently residence times are longer in the oxidizer than in the transport-bed reactor. [Pg.457]

Other aldehydes which have been used in the reaction are pro-panal, butanal, glycolaldehyde, 3-hydroxybutanal, and a number of phenylacetaldehydeand benzaldehyde derivatives. Whereas condensation of tryptophan with acetaldehyde takes place even at room temperature and pH 6.7, the reactions with chloral, chloroacetaldehyde, and crotonaldehyde fail entirely. [Pg.85]

Synthesis and chemistry of substituted l-azabicyclo[1.1.0]butanes 97SL1029. Synthesis of aziridines via stereoselective reactions with imines 99PAC1033. [Pg.243]

Purely parallel reactions are e.g. competitive reactions which are frequently carried out purposefully, with the aim of estimating relative reactivities of reactants these will be discussed elsewhere (Section IV.E). Several kinetic studies have been made of noncompetitive parallel reactions. The examples may be parallel formation of benzene and methylcyclo-pentane by simultaneous dehydrogenation and isomerization of cyclohexane on rhenium-paladium or on platinum catalysts on suitable supports (88, 89), parallel formation of mesityl oxide, acetone, and phorone from diacetone alcohol on an acidic ion exchanger (41), disproportionation of amines on alumina, accompanied by olefin-forming elimination (20), dehydrogenation of butane coupled with hydrogenation of ethylene or propylene on a chromia-alumina catalyst (24), or parallel formation of ethyl-, methylethyl-, and vinylethylbenzene from diethylbenzene on faujasite (89a). [Pg.24]

The second option involves the incorporation of either chiral amines or chiral alcohols into the heteroatom-carbene side chain (R ), which represents the most versatile approach to diastereoselective benzannulation. The optically pure (2R,3R)-butane-2,3-diol was used to tether the biscarbene complex 37. The double intramolecular benzannulation reaction with diphenylbutadiyne allowed introduction of an additional stereogenic element in terms of an axis... [Pg.136]

The photo-Kolbe reaction is the decarboxylation of carboxylic acids at tow voltage under irradiation at semiconductor anodes (TiO ), that are partially doped with metals, e.g. platinum [343, 344]. On semiconductor powders the dominant product is a hydrocarbon by substitution of the carboxylate group for hydrogen (Eq. 41), whereas on an n-TiOj single crystal in the oxidation of acetic acid the formation of ethane besides methane could be observed [345, 346]. Dependent on the kind of semiconductor, the adsorbed metal, and the pH of the solution the extent of alkyl coupling versus reduction to the hydrocarbon can be controlled to some extent [346]. The intermediacy of alkyl radicals has been demonstrated by ESR-spectroscopy [347], that of the alkyl anion by deuterium incorporation [344]. With vicinal diacids the mono- or bisdecarboxylation can be controlled by the light flux [348]. Adipic acid yielded butane [349] with levulinic acid the products of decarboxylation, methyl ethyl-... [Pg.140]

Recent efforts in the development of efficient routes to highly substituted yS-ami-no acids based on asymmetric Mannich reactions with enantiopure sulfmyl imine are worthy of mention. Following the pioneering work of Davis on p-tolu-enesulfmyl imines [116], Ellman and coworkers have recently developed a new and efficient approach to enantiomerically pure N-tert-butanesulfmyl imines and have reported their use as versatile intermediates for the asymmetric synthesis of amines [91]. Addition of titanium enolates to tert-butane sulfmyl aldimines and ketimines 31 proceeds in high yields and diastereoselectivities, thus providing general access to yS -amino acids 32 (Scheme 2.5)... [Pg.44]

The first attempted asymmetric intermolecular Stetter reaction was reported by Enders and co-workers who showed in 1989 that reaction of n-butanal 142 with chalcone 143 in the presence of the NHC derived from thiazolium salt 144 generated Stetter product 145 in 39% ee but only 4% yield (Scheme 12.30) [66],... [Pg.279]

Polyether-based foams account for more than 90% of all flexible polyurethane foams. The properties of foams are controlled by the molecular structure of the precursors and the reaction conditions. In general, density decreases as the amount of water increases, which increases the evolution of carbon dioxide. However, the level of water that can be used is limited by the highly exothermic nature of its reaction with isocyanate, which carries with it the risk of self-ignition of the foamed product. If very low density foams are desired, additional blowing agents, such as butane, are incorporated within the mixing head. [Pg.390]

Titanium enolates.1 This Fischer carbene converts epoxides into titanium enolates. In the case of cyclohexene oxide, the product is a titanium enolate of cyclohexanone. But the enolates formed by reaction with 1,2-epoxybutane (equation I) or 2,3-epoxy butane differ from those formed from 2-butanone (Equation II). Apparently the reaction with epoxides does not involve rearrangement to the ketone but complexation of the epoxide oxygen to the metal and transfer of hydrogen from the substrate to the methylene group. [Pg.49]

The reactions of butadiene were very similar to the reactions of butane and 1-butene with addition being the most common reaction. The [V204]+ ion was the only ion to induce fission of butadiene but this was a minor pathway compared with the addition reaction. Only [V307]+ was involved in a dehydration reaction with butadiene to give the [V306C2H3]+ ion. [Pg.412]


See other pages where 4- butane reaction with is mentioned: [Pg.457]    [Pg.253]    [Pg.513]    [Pg.116]    [Pg.790]    [Pg.1289]    [Pg.503]    [Pg.67]    [Pg.273]    [Pg.94]    [Pg.481]    [Pg.308]    [Pg.142]    [Pg.161]    [Pg.217]    [Pg.544]    [Pg.41]    [Pg.687]    [Pg.395]    [Pg.96]    [Pg.78]    [Pg.31]    [Pg.58]    [Pg.80]    [Pg.53]    [Pg.268]    [Pg.364]    [Pg.261]    [Pg.50]   


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Butanal, reaction with

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