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From alkylation

A wide class of aiyl-based quaternary surfactants derives from heterocycles such as pyridine and quinoline. The Aralkyl pyridinium halides are easily synthesized from alkyl halides, and the paraquat family, based upon the 4, 4 -bipyridine species, provides many interesting surface active species widely studied in electron donor-acceptor processes. Cationic surfactants are not particularly useful as cleansing agents, but they play a widespread role as charge control (antistatic) agents in detergency and in many coating and thin film related products. [Pg.2577]

Alkyl and aryl iodides usually react with magnesium more rapidly than the corresponding bromides, and the bromides very much more rapidly than the chlorides. Aryl (as distinct from alkyl) chlorides have usually only a slow reaction with magnesium and are therefore very rarely used. With alkyl and aryl iodides in particular, however, a side reaction often occurs with the formation of a hydrocarbon and magnesium iodide ... [Pg.281]

Anilides and a-Naphthalides. The Grignard reagents prepared from alkyl halides react with phenyl isocyanate (CgHjN=C=0) or with a-uaphthy l isocyanate (C,oH, N=C=0) to yield addition products that are converted by hydrolysis into anihdes and a-naphthalides respectively RX + Mg —> RMgX... [Pg.290]

Alkyl mercuric halides. Grignard reagents, prepared from alkyl halides, react with a mercuric halide that contains the same halogen as the reagent to form alkyl mercuric halides ... [Pg.291]

Alkvl Azides from Alkyl Bromides and Sodium Azide General procedure for the synthesis of alkyl azides. In a typical experiment, benzyl bromide (360 mg, 2.1 mmol) in petroleum ether (3 mL) and sodium azide (180 mg, 2.76 mmol) in water (3 mL) are admixed in a round-bottomed flask. To this stirred solution, pillared clay (100 mg) is added and the reaction mixture is refluxed with constant stirring at 90-100 C until all the starting material is consumed, as obsen/ed by thin layer chromatographv using pure hexane as solvent. The reaction is quenched with water and the product extracted into ether. The ether extracts are washed with water and the organic layer dried over sodium sulfate. The removal of solvent under reduced pressure affords the pure alkyl azides as confirmed by the spectral analysis. ... [Pg.156]

The carbonylation of aryl iodides in the presence of alkyl iodides and Zn Cu couple affords aryl alkyl ketones via the formation of alkylzinc species from alkyl iodides followed by transmetallation and reductive elimination[380]. The Pd-catalyzed carbonylation of the diaryliodonium salts 516 under mild conditions in the presence of Zn affords ketones 517 via phenylzinc. The a-diketone 518 is formed as a byproduct[381],... [Pg.200]

Section 5 6 Electron release from alkyl substituents stabilizes a double bond In gen eral the order of alkene stability is... [Pg.221]

We now have a new problem Where does the necessary alkene come from Alkenes are prepared from alcohols by acid catalyzed dehydration (Section 5 9) or from alkyl halides by dehydrohalogenation (Section 5 14) Because our designated starting material is tert butyl alcohol we can combine its dehydration with bromohydrm formation to give the correct sequence of steps... [Pg.266]

Phosphorus ylides are prepared from alkyl halides by a two step sequence The first step is a nucleophilic substitution of the 8 2 type by triphenylphosphme on an alkyl halide to give an alkyltriphenylphosphonium salt... [Pg.733]

Because nitriles can be prepared from alkyl halides by nucleophilic substitution with cyanide ion the overall process RX RC=N RCH2NH2 leads to primary amines that have one more carbon atom than the starting alkyl halide... [Pg.932]

Ph) or OPh, the last two of which may be substituted by up to three groups selected from alkyl, alkoxy, sulfonate, carboxylate, alkylthio-,... [Pg.46]

The ultimate fate of the oxygen-centered radicals generated from alkyl hydroperoxides depends on the decomposition environment. In vinyl monomers, hydroperoxides can be used as efficient sources of free radicals because vinyl monomers generally are efficient radical scavengers which effectively suppress induced decomposition. When induced decomposition occurs, the hydroperoxide is decomposed with no net increase of radicals in the system (see eqs. 8, 9, and 10). Hydroperoxides usually are not effective free-radical initiators since radical-induced decompositions significantly decrease the efficiency of radical generation. Thermal decomposition-rate studies in dilute solutions show that alkyl hydroperoxides have 10-h HLTs of 133—172°C. [Pg.104]

Syimnetiical dialkyl peroxides have been prepared from alkyl hydroperoxides and lead tetraacetate. If tertiary dihydroperoxides are used, then cychc... [Pg.109]

In the foUowiag cases, only those reactions ia which there is no chain growth, or at most dimerisation, are considered (see Olefin polymers). Alkyl titanium haUdes can be prepared from alkyl aluminum derivatives. The ring stmcture imparts regiospecificity to the ensuing carbometalation (216) ... [Pg.155]

Inductive and resonance stabilization of carbanions derived by proton abstraction from alkyl substituents a to the ring nitrogen in pyrazines and quinoxalines confers a degree of stability on these species comparable with that observed with enolate anions. The resultant carbanions undergo typical condensation reactions with a variety of electrophilic reagents such as aldehydes, ketones, nitriles, diazonium salts, etc., which makes them of considerable preparative importance. [Pg.166]

Proton loss from alkyl groups a or 7 to a cationic center in an azolium ring is often easy. The resulting neutral anhydro bases or methides (cf. 381) can sometimes be isolated they react readily with electrophilic reagents to give products which can often lose another proton to give new resonance-stabilized anhydro bases. Thus the trithione methides are anhydro bases derived from 3-alkyl-l,2-dithiolylium salts (382 383) (66AHC(7)39). These... [Pg.89]

Synthesis of primary amines from alkyl halides with hexamelhylenetelramines. [Pg.91]

One of the best leaving groups is molecular nitrogen in alkyl diazonium ions. Diazonium ions are generated by nitrosation of primaiy amines. The diazonium ions generated from alkyl amines are veiy unstable and immediately decompose with loss of nitrogen. [Pg.298]

Despite these early successes in the commercialization of acrylic polymers, no acrylic PSAs were manufactured on a larger scale until many years later. One of the primary reasons for the initial commercial failure of the acrylic PSAs was their lack of cohesive strength. Unlike the higher Tg, plastic-like polymers obtained from monomers like methylmethacrylate, polymers synthesized from alkyl acrylates typically formed sticky, cold-flowing materials with little if any utility. [Pg.485]

The homopolymers, which are formed from alkyl cyanoacrylate monomers, are inherently brittle. For applications which require a toughened adhesive, rubbers or elastomers can be added to improve toughness, without a substantial loss of adhesion. The rubbers and elastomers which have been used for toughening, include ethylene/acrylate copolymers, acrylonitrile/butadiene/styrene (ABS) copolymers, and methacrylate/butadiene/styrene (MBS) copolymers. In general, the toughening agents are incorporated into the adhesive at 5-20 wt.% of the monomer. [Pg.857]

The demand for aviation gasoline during World War II was so great that isobutanc from alkylation feedstock was insufficient. This deficiency was remedied by isomerization of abundant normal butane into isobutane using the isomerization catalyst aluminum chloride on alumina promoted by hydrogen chloride gas. [Pg.291]

This reaction sequence is called the acetoacetic ester synthesis. It is a standard procedure for the preparation of ketones from alkyl halides, as the conversion of 1-bromobutane to 2-heptanone illustrates. [Pg.895]

Primaty amines may be prepared from alkyl halides using phthalimide. This is called the Gabriel amine synthesis. [Pg.206]


See other pages where From alkylation is mentioned: [Pg.187]    [Pg.209]    [Pg.48]    [Pg.235]    [Pg.6]    [Pg.106]    [Pg.200]    [Pg.216]    [Pg.895]    [Pg.281]    [Pg.262]    [Pg.28]    [Pg.485]    [Pg.259]    [Pg.206]    [Pg.1541]    [Pg.225]    [Pg.39]   
See also in sourсe #XX -- [ Pg.22 ]




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