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Alkyl reaction with ethylene

Lithiated indoles can be alkylated with primary or allylic halides and they react with aldehydes and ketones by addition to give hydroxyalkyl derivatives. Table 10.1 gives some examples of such reactions. Entry 13 is an example of a reaction with ethylene oxide which introduces a 2-(2-hydroxyethyl) substituent. Entries 14 and 15 illustrate cases of addition to aromatic ketones in which dehydration occurs during the course of the reaction. It is likely that this process occurs through intramolecular transfer of the phenylsulfonyl group. [Pg.95]

In the production of a-olefins, ethylene reacts with an aluminum alkyl at relatively low temperature to produce a higher aLkylalumiaum. This is then subjected to a displacement reaction with ethylene at high temperatures to yield a mixture of a-olefins and triethylalumiaum. In an alternative process, both reactions are combiaed at high temperatures and pressures where triethylalumiaum fuactioas as a catalyst ia the polymerization process. [Pg.433]

Functionalization of these reactive anionic chain ends can be achieved by a variety of methods all based on the general concepts of carbanion chemistry. For example, reaction with C02 or succinnic anhydride leads to the carboxy terminated derivatives [10], while hydroxy-terminated polymers can be easily obtained by reaction with ethylene oxide (Scheme 3) [11]. In select functionalization reactions, such as alkylation with p-vinyl benzyl chloride, the nucleophilicity of the carbanionic species may be necessary and this can be achieved by reaction of the chain end with 1,1-diphenylethene followed by functionalization [12,13]. [Pg.48]

Alkylation of benzene is old technology. The French chemist, Charles Friedel, with his American partner, James Crafts, in 1877, stumbled (almost literally) across the technique for alkylating benzene with amyl chloride (C5H11CI). The use of a metallic catalyst, in this case aluminum, was the key. The Friedel-Crafts reaction is classical and remains a principal route for alkylating benzene with ethylene to make EB. [Pg.120]

The reaction of toluene with propylene and higher olefins is similar to that of toluene with ethylene. In contrast to the acid-catalyzed alkylation of aromatics, the base-catalyzed reaction of toluene with propylene takes place less rapidly than the reaction with ethylene. With more severe conditions, such as temperatures of 225-250°, the reaction of toluene with propylene may be made to proceed satisfactorily, but butylenes yield only small amounts of products even at 300°, as reported by Pines and Mark 20). Such conditions result not only in more hydrogen transfer, but alkyl-group... [Pg.129]

Manufacturing processes and equipment are similar to those employed for alcohol ethoxylate preparation. In the absence of steric hindrance, ethylene oxide reacts with both hydrogens of primary amines at relatively low temperatures (90—120°C) without added catalysts (105). When the nitrogen atom is hindered, as it is in the Triton RW products, only one of the amino hydrogens reacts with ethylene oxide. Once this reaction is complete, a basic catalyst is added and ethoxylation proceeds in the manner of the alcohol-based nonionics. In IV-alkyl-l,3-propanediamine, all three amino hydrogens are available for reaction with ethylene oxide. N-Alkyl-1,3-propanediamines are prepared from fatty monoamines and acrylonitrile, followed by reduction of the resulting 3-cyanoethylalkyl amine. [Pg.257]

It may be concluded that primary alkyl chlorides undergo peroxide-induced, hydrogen chloride-promoted, alkylation with ethylene to yield products formed by alkylation at a tertiary carbon atom, at a penultimate secondary carbon atom, or at a primary carbon atom holding a chlorine atom. In the absence of hydrochloric acid, n-butyl chloride underwent little peroxide-induced reaction with ethylene presumably because hydrogen chloride is necessary for propagating the reaction chain via abstraction of hydrogen from the hydrogen chloride to produce the ethylated product and a chlorine atom which maintains the chain by abstraction from the alkyl chloride. [Pg.163]

Certain halogenated compounds will condense with paraffinic, olefinic, or aromatic hydrocarbons. Catalysts for these reactions are of the Ftiedel-Crafts type. Thus, the condensation of alkyl halides with ethylene in the presence of aluminum chloride, zinc chloride, iron chloride, etc., furnishes higher alkyl halides. An example is the reaction of /-butyl chloride and ethylene to form l-chloro-3,3-dimethylbutane (75%). ... [Pg.59]

Of the three fatty amines, the tertiary fatty amines, with three alkyl groups, find the most application in industries. They are further classified into three types (1) symmetrical trifatty amine (R3N), in which all three alkyl chains are identical (2) asymmetrical dimethyl fatty amine [RN(CH3)2] or methyl difatty amine (R2NCH3) and (3) those derived from primary or secondary amine by the reaction with ethylene oxide. These asymmetrical fatty amines are the bases for the manufacture of organomodified clay for the petroleum industry, biocides, and algicides. [Pg.3033]

Dimersol E is used to upgrade C2 + C3 fuel gas. Co-oligomerization of ethylene and propene leads to a gasoline stream very similar to the Dimersol G product. Mixed butenes are also obtained with Dimersol E (from ethylene dimerization). They can be used in paraffinic alkylation or to make propene through a subsequent cross-metathesis reaction with ethylene. [Pg.91]

The Phillips catalyst is not alkylated when it goes into the reactor, and metal alkyl cocatalysts are not normally used. Thus, in contrast to Ziegler, Ballard, or metallocene catalysts, the Phillips catalyst has no Cr-alkyl bond into which ethylene may be inserted. Instead, the chromium somehow reacts with ethylene to generate such a bond. This characteristic is not unique, as many catalyst types also display this ability.8 This issue has been the source of much interest and speculation for half a century. On some catalysts, CO reduction is known to cleanly produce Cr(II). Reaction with ethylene could involve a formal oxidation [52,94,141,250-252,269,322-325,339-345] and many pathways involving Cr(IV) have been proposed, sometimes based on organochromium analogs, such as shown in Scheme 8 [94,250-252,315-319,321-325,342,346-349]. [Pg.169]

The N-9 N-7 ratio of products varies with time when alkylations employ a Michael acceptor like methyl acrylate, for here the alkylation is reversible and the concentration of thermodynamic product can build up. " Regiospecific 7-alkylations can be achieved via the quatemisation of a 9-riboside followed by hydrolytic removal of the sugar residue, as illustrated by a reaction with ethylene oxide. Alkylation on N-7 in nucleic acids is the mechanism of mutagenesis/carcinogenesis by some natural toxins, such as aflatoxin. ... [Pg.518]

Diastereoselective [2+2] photocycloaddition of a polymer-supported cyclic chiral enone with ethylene has been reported (Scheme 12.33) [43]. The auxiliary was derived from (-)-8-(p-methoxyphenyl) menthol (87). Protection of the secondary alcohol and demethylation were carried out to give (-)-8-(p-hydroxyphenyl)menthyl acetate (88). An alkyl linker was introduced and finally loaded to poly (ethylene glycol) grafted Wang resin. Deprotection of the alcohol functionality was followed by esterification with cyclohexen-3-one-l-carboxylic acid to provide the chiral enone 89. The photochemical reaction with ethylene was performed by irradiating with light (k > 280 nm). Trifluoroacetic acid (TFA) or aqueous hydrolysis with... [Pg.352]

Dialkylaluminum halides, alkoxides, phenoxides and thiolates react with ethylene only in the presence of R3AI (via alkyl group exchange and growth of the trialkylaluminum) ". The strong association in R2AINR2 prevents reaction with ethylene even in the presence " of R3AI. [Pg.223]

Ziegler and Gellert (6) in 1949 showed that aluminum hydride reacts with ethylene at 60-80 °C to yield triethylaluminura. At 100-120 C reaction with additional ethylene leads to formation of higher alkyls of aluminum (Reaction 1). At temperatures above 120 C higher aluminum alkyls react with ethylene through a... [Pg.69]


See other pages where Alkyl reaction with ethylene is mentioned: [Pg.47]    [Pg.383]    [Pg.257]    [Pg.240]    [Pg.3]    [Pg.88]    [Pg.1052]    [Pg.1436]    [Pg.330]    [Pg.137]    [Pg.240]    [Pg.171]    [Pg.240]    [Pg.383]    [Pg.97]    [Pg.627]    [Pg.627]    [Pg.159]    [Pg.1774]    [Pg.378]    [Pg.240]    [Pg.33]    [Pg.313]    [Pg.324]    [Pg.54]    [Pg.54]    [Pg.1773]    [Pg.366]    [Pg.899]   
See also in sourсe #XX -- [ Pg.159 ]




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