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Alcohols, from addition

The developer is generally a solvent in which the components of the mixture are not too soluble and is usually a solvent of low molecular weight. The adsorbent is selected so that the solvent is adsorbed somewhat but not too strongly if the solvent is adsorbed to some extent, it helps to ensure that the components of the mixture to be adsorbed will not be too firmly bound. Usually an adsorbate adheres to any one adsorbent more firmly in a less polar solvent, consequently when, as frequently occurs, a single dense adsorption zone is obtained with light petroleum and develops only slowly when washed with this solvent, the development may be accelerated by passing to a more polar solvent. Numerous adsorbat are broken up by methyl alcohol, ethyl alcohol or acetone. It is not generally necessary to employ the pure alcohol the addition from 0 5 to 2 per cent, to the solvent actually used suffices in most cases. [Pg.161]

Atophan. In a 1 litre round-bottomed flask, equipped with a reflux condenser, place 25 g. (24 ml.) of purified benzaldehyde (Section IV,115), 22 g. of freshly-distilled P3 ruvic acid and 200 ml. of absolute ethyl alcohol. Heat the mixture to tlie boiling point on a water bath and add slowly, with frequent shaking, a solution of 23 g. (22 -5 ml.) of pure aniline in 100 ml. of absolute ethyl alcohol. The addition usually occupies about 1 hour. Reflux the mixture on a water bath for 3 hours, and allow to stand overnight. Filter off the crude atophan (1) at the pump and wash the crystals with a little ether. Recrystallise from ethyl alcohol (about 20 ml. per gram). The yield of pure 2-phenvlquinoUne-4-carboxvUc acid, m.p. 210°, is 30 g. [Pg.1011]

The elimination of alcohol from P-alkoxypropionates can also be carried out by passing the alkyl P-alkoxypropionate at 200—400°C over metal phosphates, sihcates, metal oxide catalysts (99), or base-treated zeoHtes (98). In addition to the route via oxidative carbonylation of ethylene, alkyl P-alkoxypropionates can be prepared by reaction of dialkoxy methane and ketene (100). [Pg.156]

The propylene-based chemicals, n- and isobutanol and 2-ethyl-1-hexanol [104-76-7] (2-EH) dominate the product spectmm. These chemicals represent 71% of the world s total oxo chemical capacity. In much of the developed world, plasticizers (qv), long based on 2-EH, are more often and more frequendy higher molecular weight, less volatile Cg, and C q alcohols such as isononyl alcohol, from dimerized normal butenes isodecanol, from propylene trimer and 2-propyl-1-heptanol, from / -butenes and aldol addition. Because of the competition from the higher molecular weight plasticizer alcohols,... [Pg.472]

Sulfuric acid is about one thousand times more reactive with isobutylene than with the 1- and 2-butenes, and is thereby very useful in separating isobutylene as tert-huty alcohol from the other butenes. The reaction is simply carried out by bubbling or stirring the butylenes into 45—60% H2SO4. This results in the formation of tert-huty hydrogen sulfate. Dilution with water followed by heat hydrolyzes the sulfate to form tert-huty alcohol and sulfuric acid. The Markovnikov addition implies that isobutyl alcohol is not formed. The hydration of butylenes is most important for isobutylene, either directiy or via the butyl hydrogen sulfate. [Pg.363]

Isopropyl Ether. Isopropyl ether is manufactured by the dehydration of isopropyl alcohol with sulfuric acid. It is obtained in large quantities as a by-product in the manufacture of isopropyl alcohol from propylene by the sulfuric acid process, very similar to the production of ethyl ether from ethylene. Isopropyl ether is of moderate importance as an industrial solvent, since its boiling point Hes between that of ethyl ether and acetone. Isopropyl ether very readily forms hazardous peroxides and hydroperoxides, much more so than other ethers. However, this tendency can be controlled with commercial antioxidant additives. Therefore, it is also being promoted as another possible ether to be used in gasoline (33). [Pg.429]

Hydroboration - regloseiective and stereoselective (syn) addition of BH3 (RBH2, R2BH) to olefins. Synthesis of alcohol including optically active alcohols from olefins. Also useful In synthesis of ketones by stitching ot olefins and CO... [Pg.51]

The preparation of neopentyl alcohol from diisobutylene herein described represents an example of acid-catalyzed addition of hydrogen peroxide to a branched olefin, followed by an acid-catalyzed rearrangement of the tertiary hydroperoxide formed. In addition to neopentyl alcohol, there are formed acetone and also small amounts of methanol and methyl neopentyl ketone by an alternative rearrangement of the hydroperoxide. [Pg.79]

When saturated steroidal ketones are reduced in ammonia, an alcohol is usually present to act as a proton donor and high yields of steroidal alcohols are obtained. Under these conditions, reduction probably proceeds by protonation of the radical-anion (or ketyl) (61), which results from a one electron addition to the carbonyl group, followed by addition of a second electron and proton. Barton has proposed that reduction proceeds via protonation of the dianion (62) arising from addition of two electrons to the carbonyl group. This proposal implies that the ketyl (61) undergoes addition of a second electron in preference to undergoing protonation by the... [Pg.33]

In order to obtain good yields, it is important to use dry solvent and reagents. The commercially available t-butyl hydroperoxide contains about 30% water for stabilization. For the use in a Sharpless epoxidation reaction the water has to be removed first. The effect of water present in the reaction mixture has for example been investigated by Sharpless et al. for the epoxidation of (E)-a-phenylcinnamyl alcohol, the addition of one equivalent of water led to a decrease in enantioselectivity from 99% e.e. to 48% e.e. [Pg.256]

A mixture of 24.1 g (0.10 mol) of 3-o-methoxyphenoxy-2-hydroxy-1 -propyl carbamate and 6.0 g (0.10 mol) of urea was heated rapidly to the temperature range of 180°C to 200°C, and maintained there for five hours. The reaction melt was poured into 50% ethyl alcohol, from which the product crystallized as a white solid. The crude yield was 18.3 g (82%) melting point 131.5°C to 137 t. Crystallization from water and 95% alcohol gave 9.0 g (40.3%) of pure 5-o-methoxyphenoxymethyl-2-oxazolidone melting point 141°Cto 143. This melting point was not depressed when the material was mixed with an authentic sample. In additional runs acetone was used Instead of ethyl alcohol with equivalent results. [Pg.936]

Benzol and other alcohol-hased additives improved octane number, up to a point. Experiments using alcohol (ethanol, methanol) as a replacement for gasoline began as early as 1906. In 1915, Hetu-y Ford announced a plan to extract alcohol from grain to power his new Fordson tractor, an idea that never achieved commercial success. [Pg.551]

The addition of ethylene oxide to the alcohol causes a decrease in the melting point of the corresponding salt of the alcohol ether sulfate in comparison with the same alcohol sulfate. Weil et al. [65] prepared pure hexadecyl and octadecyl ether alcohols from the corresponding alkyl bromide and glycols with... [Pg.235]

The products from protonation are, of course, the same as those derived from additions of alcohols to the coordinated ligand (Section III,C). [Pg.41]

Petroleum spillages can be removed from water surfaces more efficiently with the following detergent mixture [1692], which contains mainly oxyethyl-ate fatty Cio to C20 alcohols and additional oxyethylated fatty Cn to Cyj acids with an oxyethylene chain length of one to two units. It is used in the form of an aqueous 20% to 25% emulsion, which is sprayed onto a contaminated surface. [Pg.307]

A. B. Sulejmanov, T. B. Geokchaev, and R. A. Dashdiev. Removal of petroleum spillages from water surface— using a detergent mixture containing oxyethylated fatty 10-20 C alcohols and additional oxy-ethylated fatty 11-17 C acids to improve properties. Patent SU 1803418-A, 1993. [Pg.465]


See other pages where Alcohols, from addition is mentioned: [Pg.12]    [Pg.632]    [Pg.160]    [Pg.450]    [Pg.293]    [Pg.465]    [Pg.243]    [Pg.295]    [Pg.70]    [Pg.302]    [Pg.523]    [Pg.524]    [Pg.685]    [Pg.743]    [Pg.750]    [Pg.73]    [Pg.96]    [Pg.937]    [Pg.637]    [Pg.1284]    [Pg.131]    [Pg.326]    [Pg.147]    [Pg.9]    [Pg.38]    [Pg.601]    [Pg.429]    [Pg.7]    [Pg.22]    [Pg.632]   


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Addition alcohols

Alcohol additive

Alcohols from Alkenes through Oxymercuration-Demercuration Markovnikov Addition

Alcohols from nucleophilic addition

Alcohols, from addition monoxide

Alcohols, from addition organometallics

Alcohols, from addition ozone

Alcohols, from addition procedure

Hydroxy-amides, from addition amino-alcohols

Nucleophilic addition reactions tertiary alcohol formed from

Preliminary Solvent Extraction of Gross Additives from Aqueous and Alcoholic Extractants

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