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Alkyl halides, alkylation reactions

Other catalysts which may be used in the Friedel - Crafts alkylation reaction include ferric chloride, antimony pentachloride, zirconium tetrachloride, boron trifluoride, zinc chloride and hydrogen fluoride but these are generally not so effective in academic laboratories. The alkylating agents include alkyl halides, alcohols and olefines. [Pg.509]

The process whereby aldehydes are produced from arylmethyl (also alkyl and other) halides by the action of hexamine is known as the Sommelet reaction. The reaction is essentially the conversion of an amine into an aldehyde the hexamine serves the dual role of converting the halide into the amine and the amine into the aldehyde, but its function is different in the two steps. When starting from a halide, the reaction proceeds in three stages —... [Pg.692]

In contrast to alkylations with most of the alkyl halides, the reactions of anions with ethylene oxide in organic solvents such as diethyl ether and THE... [Pg.10]

The major portion of the present chapter concerns the conversion of alcohols to alkyl halides by reaction with hydrogen halides... [Pg.142]

Alkenes are prepared by P elimination of alcohols and alkyl halides These reactions are summarized with examples m Table 5 2 In both cases p elimination proceeds m the direction that yields the more highly substituted double bond (Zaitsev s rule)... [Pg.221]

The most frequently used organocuprates are those m which the alkyl group is pri mary Steric hindrance makes secondary and tertiary dialkylcuprates less reactive and they tend to decompose before they react with the alkyl halide The reaction of cuprate reagents with alkyl halides follows the usual 8 2 order CH3 > primary > secondary > tertiary and I > Br > Cl > F p Toluenesulfonates are somewhat more reactive than halides Because the alkyl halide and dialkylcuprate reagent should both be primary m order to produce satisfactory yields of coupled products the reaction is limited to the formation of RCH2—CH2R and RCH2—CH3 bonds m alkanes... [Pg.603]

The value of alkyl halides as starting materials for the preparation of a variety of organic functional groups has been stressed many times In our earlier discussions we noted that aryl halides are normally much less reactive than alkyl halides m reactions that involve carbon-halogen bond cleavage In the present chapter you will see that aryl halides can exhibit their own patterns of chemical reactivity and that these reac tions are novel useful and mechanistically interesting... [Pg.971]

Aryl halides are less reactive than alkyl halides m reactions m which C—X bond breaking is rate determining especially m nucleophilic sub stitution reactions... [Pg.986]

Alkyl halides by reaction with the enolate anion derived from diethyl acetamidomalonate... [Pg.1150]

Addition to Carbonyl Compounds. Unlike Grignard and alkykitliium compounds, trialkylboranes are inert to carbonyl compounds. The air-catalyzed addition to formaldehyde is exceptional (373). Alkylborates are more reactive and can transfer alkyl groups to acyl halides. The reaction provides a highly chemoselective method for the synthesis of ketones (374). [Pg.319]

Figure 22 represents the main consequences on pyrazole reactivity when a positive charge is present at the 2-position of the nucleus. A similar situation occurs in the indazolium salts, which thermally decompose into an alkylindazole and an alkyl halide, a reaction sequence described by von Auwers. [Pg.217]

Reactions of alcohols with hydrogen halides (Section 4.7) Alcohols react with hydrogen halides to yield alkyl halides. The reaction is useful as a synthesis of alkyl halides. The reactivity of hydrogen halides decreases in the order HI > HBr > HCI > HF. Alcohol reactivity decreases in the order tertiary > secondary > primary > methyl. [Pg.180]

Two kinds of starting materials have been examined in nucleophilic substitution reactions to this point. In Chapter 4 we saw that alcohols can be converted to alkyl halides by reaction with hydrogen halides and pointed out that this process is a nucleophilic substitution taking place on the protonated fonm of the alcohol, with water serving as the... [Pg.350]

With enamines of cyclic ketones direct C alkylation occurs with allyl and propargyl as well as alkyl halides. The reaction is again sensitive to the polarity of the solvent (29). The pyrrolidine enamine of cyclohexanone on reaction with ethyl iodide in dioxane gave 25% of 2-ethylcyclohexanone on hydrolysis, while in chloroform the yield was increased to 32%. [Pg.121]

One of the advantages of the enamine alkylation reaction over direct alkylation of the ketone under the influenee of strong base is that the major product is the monoalkylated derivative 29,32). When dialkylation is observed, it occurs at the least substituted carbon in contrast to alkylation with base, where the a-disubstituted product is formed. Dialkylation becomes the predominant reaction when a strong organic base is added and an excess of alkyl halide is used (29). Thus 1-N-pyrrolidino-l-cyclo-hexene (28) on treatment with two moles of allyl bromide in the presence of ethyl dicyclohexylamine (a strong organic base which is not alkylated under the reaction conditions) gave a 95 % yield of 2,6-diallylcyclohexanone (29). [Pg.122]

It is a reaction of wide scope both the phosphite 1 and the alkyl halide 2 can be varied. Most often used are primary alkyl halides iodides react better than chlorides or bromides. With secondary alkyl halides side reactions such as elimination of HX can be observed. Aryl halides are unreactive. [Pg.15]

The rate of the alkylation reaction depends on the enolate concentration, since it proceeds by a SN2-mechanism. If the concentration of the enolate is low, various competitive side-reactions may take place. As expected, among those are E2-eliminations by reaction of the alkyl halide 2 with base. A second alkylation may take place with mono-alkylated product already formed, to yield a -alkylated malonic ester however such a reaction is generally slower than the alkylation of unsubstituted starting material by a factor of about 10. The monoalkylation is in most cases easy to control. Dialkylated malonic esters with different alkyl substituents—e.g. ethyl and isopropyl—can be prepared by a step by step reaction sequence ... [Pg.191]

Carboncations also form from an alkyl halide when a Lewis acid catalyst is used. Aluminum chloride is the commonly used Friedel-Crafts alkylation catalyst. Friedel-Crafts alkylation reactions have been reviewed by Roberts and Khalaf ... [Pg.263]

The alkylation reaction is limited to the use of primary alkyl bromides and alkyl iodides because acetylide ions are sufficiently strong bases to cause dehydrohalogenation instead of substitution when they react with secondary and tertiary alkyl halides. For example, reaction of bromocyclohexane with propyne anion yields the elimination product cyclohexene rather than the substitution product 1-propynylcyclohexane. [Pg.273]

We said at the beginning of this chapter that two kinds of reactions can happen when a nucleophile/Lewis base reacts with an alkyl halide. The nucleophile can either substitute for the halide by reaction at carbon or cause elimination of HX by reaction at a neighboring hydrogen ... [Pg.383]

Mechanism of the E2 reaction of an alkyl halide. The reaction takes place in a single step through a transition state in which the double bond begins to form at the same time the H and X groups are leaving. [Pg.386]

The reaction often works poorly unless an excess of the nucleophile is used because the product thiol can undergo a second S 2 reaction with alkyl halide to give a sulfide as a by-product. To circumvent this problem, thiourea, (NH2J2C=S, is often used as the nucleophile in the preparation of a thiol from an alkyl halide. The reaction occurs by displacement of the halide ion to yield an intermediate alkyl isothiourea salt, which is hydrolyzed by subsequent reaction with aqueous base. [Pg.667]

The Sn2 alkylation reaction between an enolate ion and an alkyl halide is a powerful method for making C-C bonds, thereby building up larger molecules from smaller precursors. We ll study the alkylation of many kinds of carbonyl compounds in Chapter 22. [Pg.692]

Alkylation reactions are subject to the same constraints that affect all Sn2 reactions (Section 11.3). Thus, the leaving group X in the alkylating agent R—X can be chloride, bromide, iodide, or tosylate. The alkyl group R should be primary or methyl, and preferably should be allylic or benzylic. Secondary halides react poorly, and tertiary halides don t react at all because a competing E2 elimination of HX occurs instead. Vinylic and aryl halides are also unreactive because backside approach is sterically prevented. [Pg.855]

One of the oldest and best known carbonyl alkylation reactions is the malonic ester synthesis, a method for preparing a carboxylic add from an alkyl halide while lengthening the carbon chain by two atoms. [Pg.856]

An alkylation reaction is used to introduce a methyl or primary alkyl group onto the a position of a ketone, ester, or nitrile by S 2 reaction of an enolate ion with an alkyl halide. Thus, we need to look at the target molecule and identify any methyl or primary alkyl groups attached to an a carbon. In the present instance, the target has an a methyl group, which might be introduced by alkylation of an ester enolate ion with iodomethane. [Pg.863]

There is no simple answer to this question, but the exact experimental conditions usually have much to do with the result. Alpha-substitution reactions require a full equivalent of strong base and are normally carried out so that the carbonyl compound is rapidly and completely converted into its enolate ion at a low temperature. An electrophile is then added rapidly to ensure that the reactive enolate ion is quenched quickly. In a ketone alkylation reaction, for instance, we might use 1 equivalent of lithium diisopropylamide (LDA) in lelrahydrofuran solution at -78 °C. Rapid and complete generation of the ketone enolate ion would occur, and no unreacled ketone would be left so that no condensation reaction could take place. We would then immediately add an alkyl halide to complete the alkylation reaction. [Pg.881]

Haloalkane,. see Alkyl halide Haloform reaction, 854-855 Halogen, inductive effect of, 562 resonance effect of, 563 Halogenation, aldehydes and, 846-848... [Pg.1300]


See other pages where Alkyl halides, alkylation reactions is mentioned: [Pg.725]    [Pg.167]    [Pg.339]    [Pg.148]    [Pg.638]    [Pg.167]    [Pg.593]    [Pg.330]    [Pg.338]    [Pg.280]    [Pg.960]    [Pg.1283]    [Pg.1287]    [Pg.1300]    [Pg.89]   
See also in sourсe #XX -- [ Pg.218 ]




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Acetylide anions reactions with alkyl halides

Alcohols reaction with alkyl halides

Alkenes reaction with alkyl halides

Alkyl groups alcohol reactions with hydrogen halides

Alkyl halide coupling reactions

Alkyl halide elimination reactions

Alkyl halide reaction with Gilman reagents

Alkyl halide reaction with carboxylate ions

Alkyl halide reaction with phthalimide ion

Alkyl halide reaction with thiourea

Alkyl halide reaction with tributyltin hydride

Alkyl halide substitution reactions

Alkyl halides Compounds with halogen elimination reaction

Alkyl halides Direct Process Reaction

Alkyl halides Friedel-Crafts reactions

Alkyl halides Grignard reaction

Alkyl halides Kumada cross-coupling reactions

Alkyl halides SN2 reactions

Alkyl halides alcohol reactions with hydrogen

Alkyl halides cobalt-catalyzed Heck reactions

Alkyl halides from addition reactions

Alkyl halides gas-phase reactions

Alkyl halides hydrolysis reactions

Alkyl halides nucleophilic substitution reactions

Alkyl halides reaction with acetylides

Alkyl halides reaction with water

Alkyl halides reactions

Alkyl halides reactions

Alkyl halides reactions and characterisation

Alkyl halides reactions with ambident

Alkyl halides reactions with organocopper reagents

Alkyl halides reactions with sulfur

Alkyl halides synthetic reactions with

Alkyl halides with chlorine, reaction

Alkyl halides with nitrogen, reaction

Alkyl halides, 787 dehydrogenation reactions

Alkyl halides, displacement reactions

Alkyl halides, from alcohols reactions

Alkyl halides, from nucleophilic substitution reactions

Alkyl halides, reaction with aluminum

Alkyl halides, reaction with indole Grignard

Alkyl halides, reaction with indole Grignard reagents

Alkyl halides, reactions with arene

Alkyl halides, reactions with arene Table

Alkyl halides, reactions with trimethylsilyl

Alkyl halides—continued reactions

Alkylation reactions phenols with alkyl halides

Alkyne anions reaction with alkyl halides

Ammonia reaction with alkyl halides

Aniline derivatives alkyl halide reactions

Antimony, reaction with alkyl halides

Azidation reactions alkyl halides

Azide ion reaction with alkyl halides

Benzylic reaction with alkyl halides

Butyrolactones, reactions with alkyl halide

By Reaction with Alkyl Halides

Carbocation alkyl halide reaction with Lewis

Carbocations as intermediates in reactions of alkyl halides

Catalytic asymmetric cross-coupling reactions with secondary alkyl halides

Catalytic reactions alkyl halides

Copper reactions with alkyl halides

Cross-coupling reactions alkyl halides

Cross-coupling reactions alkyl halides with Grignard reagents

Cross-coupling reactions with alkyl halides

Cyanamide reaction with alkyl halides

Cyanides, metal, reaction with alkyl halides

Cyanocuprates, reactions with alkyl halides

Dithiane anions reaction with alkyl halides

Elimination Reactions by Sml2 Reduction of Alkyl Halides

Elimination Reactions of Alkyl Halides Zaitsevs Rule

Elimination Reactions of Alkyl and Alkenyl Halides

Elimination reactions of alkyl halides

Enolate anions reaction with alkyl halides

Enolate anions, dianions reaction with alkyl halides

Enolate anions, esters, reaction with alkyl halides

Enolates reaction with alkyl halide

Ethers reaction with alkyl halides

Exchange reactions alkyl-halide

Formylation reactions alkyl halides

Friedel-Crafts reaction with alkyl halides

Gilman cuprates, reactions with alkyl halides

Grignard reaction: alkylation with mercury halides

Grignard reagents coupling reactions with alkyl halides

Grignard reagents, reaction with alkyl halides

Halide ions reaction with alkyl halides

Halides coupling reactions with primary alkyl Grignard

Halides, alkyl intramolecular reactions with

Halides, alkyl reaction with NaSH

Halides, alkyl reaction with acetoacetic ester anions

Halides, alkyl reaction with acid salts

Halides, alkyl reaction with alkoxides

Halides, alkyl reaction with alkynes

Halides, alkyl reaction with aluminum hydride reagents

Halides, alkyl reaction with amide anions

Halides, alkyl reaction with amines

Halides, alkyl reaction with aromatic compounds

Halides, alkyl reaction with carbanions

Halides, alkyl reaction with carboxylic acid salts

Halides, alkyl reaction with cyanohydrins

Halides, alkyl reaction with enamines

Halides, alkyl reaction with hexamethylenetetramine

Halides, alkyl reaction with hydrazone anions

Halides, alkyl reaction with hydrogen sulfide

Halides, alkyl reaction with hydroxide

Halides, alkyl reaction with ketone enolate anions

Halides, alkyl reaction with ketones

Halides, alkyl reaction with lithium

Halides, alkyl reaction with magnesium

Halides, alkyl reaction with malonate anions

Halides, alkyl reaction with metals

Halides, alkyl, base induced reactions

Halides, alkyl, reaction with Bu3SnH

Halides, alkyl, reaction with Lewis acids

Halides, alkyl, reaction with Subject

Halides, alkyl, reaction with acid dianions

Halides, alkyl, reaction with amino ester enolates

Halides, alkyl, reaction with amino-alcohols

Halides, alkyl, reaction with azide

Halides, alkyl, reaction with cuprates

Halides, alkyl, reaction with cyanide

Halides, alkyl, reaction with cyanoborohydride

Halides, alkyl, reaction with dimethyl sulfide

Halides, alkyl, reaction with ester dianions

Halides, alkyl, reaction with ester enolates

Halides, alkyl, reaction with ferrate

Halides, alkyl, reaction with imides

Halides, alkyl, reaction with lactone enolates

Halides, alkyl, reaction with malonate enolates

Halides, alkyl, reaction with nitrile enolates

Halides, alkyl, reaction with nitro compounds

Halides, alkyl, reaction with organocuprates

Halides, alkyl, reaction with organolithium reagents

Halides, alkyl, reaction with phthalimide

Halides, alkyl, reaction with succinimide

Halides, alkyl, reaction with sulfides

Heck-type Reaction of Alkyl Halides with Styrenes

Hydroxide, potassium reaction with alkyl halides

Hydroxy halides, alkylation reaction, with alkali

I Reactions of Alkyl Halides Nucleophilic Substitutions and Eliminations

Indole compounds alkyl halide reactions

Intermolecular reactions alkyl halides

Iodide, potassium reaction rates with alkyl halides

Iodide, sodium reaction with alkyl halides

Iron, reaction with alkyl halides

Key Concepts—Alkyl Halides and Elimination Reactions

Kumada cross-coupling reactions, palladium alkyl halides

Lewis acid alkyl halide reactions

LiAlH4, reaction with alkyl halides

Lithium, vinylalkylation reaction with alkyl halides

Magnesium reaction of with alkyl and aryl halide

Magnesium reaction with alkyl halides, mechanism

Magnesium, reaction with alkyl halides form Grignard reagents

Magnesium-alkyl halide reaction

Metal phosphites reaction with alkyl halides

Nickel catalysts alkyl halide reactions

Nitrite, sodium reaction with alkyl halides

Nucleophiles alkyl halide substitution reactions

Nucleophilic substitution reactions of alkyl halides

Organocopper compounds, reactions with alkyl halides

Organometallic compounds reaction with alkyl halides

Organozinc reagents cross-coupling reactions with alkyl halides

Oxazine anions, reaction with alkyl halides

Oxazine anions, reaction with alkyl halides alkylation

Palladium, phenylbis catalysis arylmagnesium halide reaction with alkyl halides

Phosphines alkyl halide reactions

Phosphines reaction with alkyl halides

Phosphines reaction with alkyl halides, kinetics

Phosphoramidic acid, N- diethyl ester reaction with alkyl halides

Phosphorane, iminovinylidenetriphenylphosphonium ylide synthesis reactions with alkyl halides

Phosphorus, reaction with alkyl halides

Primary alkyl coupling reactions with alkenyl halides

Primary alkyl coupling reactions with aromatic halides

Primary alkyl halides reactions

Primary alkyl reactions with alkenyl halides

REACTIONS OF ALKYL HALIDES

Radicals, coupling reactions with alkyl halides

Reaction CXIX.—Action of Silver Nitrite on Alkyl Halides

Reaction CXXV.—Action of Alkyl Halides on Phthalimide (Potassium Salt)

Reaction XIV.—(a) Action of Magnesium Alkyl or Aryl Halide on Aldehydes and Ketones (Grignard)

Reaction of Alkyl, Alkenyl, and Aryl Halides with Metals

Reaction of Amines with Alkyl Halides

Reaction of Lithiated Bis(methylthio)methane with Alkyl Halides

Reaction of alkyl halides with sulfites and sulfinic acids

Reaction of stabilized carbanions (enolates) with alkyl halides (enolate alkylation)

Reaction with Alkyl and Aryl Halides

Reaction with alkyl halides

Reaction with alkyl halides to form

Reactions alkyl halides, kinetics

Reactions of Alkyl Halides Grignard Reagents

Reactions of Alkyl Halides Nucleophilic Substitutions and Eliminations

Reactions of Alkyl Halides Substitution and Elimination

Reactions of Alkyl Halides The Substitution Reaction

Reactions with Simple Alkyl Halides

Reactions with activated alkyl halides

Reactivity, alkyl halides with reactions

Rearrangement Reactions of Alkyl and Alkenyl Halides

Reduction reaction kinetics alkyl halides

Reduction reactions alkyl halides

Secondary alkyl halides acetylide anion reactions with

Secondary alkyl halides reactions

Silver cyanide, reaction with alkyl halides in synthesis of isocyanides

Silver nitrate, reaction with alkyl halides

Silver reaction with alkyl halides

Sn2 reaction of alkyl halides

Sn2 substitution reactions conversion of alcohols to alkyl halides

SnI reaction of alkyl halides

Sodium acetylide reaction with, alkyl halides

Sodium reaction with alkyl halides

Sodium sulfide, reaction with alkyl halides

Stereoselective reactions dehydrohalogenation of alkyl halides

Substitution reactions of alkyl halides

Sulfones anions, reaction with alkyl halides

Tertiary alkyl coupling reactions with alkenyl halides

Tetracarbonylferrate reaction with alkyl halides

The Reaction with Alkyl Halides

Thiocyanates reaction with alkyl halides

Thioethers reaction with alkyl halides

Thiol reaction with alkyl halides

Thiolate ions reaction with alkyl halides

Thiols reaction with alkyl halides

Thioureas reaction with alkyl halides

Trialkyltin hydride-alkyl halide reactions

Triphenylphosphine reaction with alkyl halides

Water alkyl halide-metal reaction

Zinc, reaction with alkyl halides

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