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Primary alkyl

Primary alkyl halide slowest rate of El elimination [Pg.219]

Methyl and primary alkyl halides especially iodides work best Elimination becomes a problem with secondary and tertiary alkyl halides [Pg.603]

Tertiary alkyl > secondary alkyl > primary alkyl > methyl [Pg.737]

Compound A (C7Hi5Br) is not a primary alkyl bromide It yields a single alkene (compound B) on being heated with sodium ethoxide in ethanol Hydrogenation of compound B yields 2 4 dimethylpentane Identify compounds A and B [Pg.278]

Nucleophilic substitution results when primary alkyl halides are treated with amines [Pg.937]

The alkyl halide must be one that reacts readily by an 8 2 mechanism Thus methyl and primary alkyl halides are the most effective alkylating agents Elimination competes with substitution when secondary alkyl halides are used and is the only reac tion observed with tertiary alkyl halides [Pg.1008]

Addition of a bromine atom to C 2 gives a primary alkyl radical [Pg.243]

Effect of Chain Branching on Reactivity of Primary Alkyl Bromides Toward Substitution Under Sn2 Conditions  [Pg.336]

One drawback to Fnedel-Crafts alkylation is that rearrangements can occur espe cially when primary alkyl halides are used For example Friedel-Crafts alkylation of benzene with isobutyl chloride (a primary alkyl halide) yields only tert butylbenzene [Pg.482]

The desired 8 2 substitution pathway is observed only with methyl and primary alkyl halides [Pg.372]

Although the yields are often poor, especially for halides other than primary alkyl halides, it remains a valuable method for synthesizing unsymmetrical ethers. [Pg.426]

These compounds are sources of the nucleophilic anion RC=C and their reaction with primary alkyl halides provides an effective synthesis of alkynes (Section 9 6) The nucleophilicity of acetylide anions is also evident m their reactions with aldehydes and ketones which are entirely analogous to those of Grignard and organolithium reagents [Pg.597]

Anions of acetylene and terminal alkynes are nucleophilic and react with methyl and primary alkyl halides to form carbon-carbon bonds by nucleophilic substitution Some useful applications of this reaction will be discussed m the following section [Pg.370]

Ethyl (CH3CH2—) heptyl [CH3(CH2)5CH2—] and octadecyl [CH3(CH2)i6CH2—] are examples of primary alkyl groups [Pg.74]

Lithium diarylcuprates are prepared m the same way as lithium dialkylcuprates and undergo comparable reactions with primary alkyl halides [Pg.603]

Because fhe new carbon-carbon bond is formed by an 8 2 lype reaction fhe alkyl halide musl nol be slerically hindered Melhyl and primary alkyl halides work besl secondary alkyl halides give lower yields Tertiary alkyl halides fail reacting only by elimination nol subslilulion [Pg.894]

Infrared The absorptions of interest m the IR spectra of amines are those associated with N—H vibrations Primary alkyl and arylammes exhibit two peaks m the range 3000-3500 cm which are due to symmetric and antisymmetric N—H stretching modes [Pg.951]

Friedel-Crafts acylation followed by Clemmensen or Wolff-Kishner reduction is a standard sequence used to introduce a primary alkyl group onto an aromatic ring [Pg.509]

The major limitation to this reaction is that synthetically acceptable yields are obtained only with methyl halides and primary alkyl halides Acetylide anions are very basic much more basic than hydroxide for example and react with secondary and ter tiary alkyl halides by elimination [Pg.372]

Those derived from isobutane are the 2 methylpropyl (isobutyl) group and the 1 1 dimethylethyl (tert butyl) group Isobutyl is a primary alkyl group because its poten tial point of attachment is to a primary carbon tert Butyl is a tertiary alkyl group because Its potential point of attachment is to a tertiary carbon [Pg.74]

Carbocations usually generated from an alkyl halide and aluminum chloride attack the aromatic ring to yield alkylbenzenes The arene must be at least as reactive as a halobenzene Carbocation rearrangements can occur especially with primary alkyl hal ides [Pg.510]

Triraethylsilylation of allenyllithium afforded predominantly HCsCCH2SiMe3, while in the cases of the homologues of allene (R = CH3 or primary alkyl) 10-20% contamination by RCsCCHjSiMe3, probably formed by trimethylsilylation of RC(Li )=C=CH2, was present. [Pg.37]

As stated above, intermolecular coupling reactions between carbon atoms are of limited use. In the classical Wurtz reaction two identical primary alkyl iodide molecules are reduced by sodium. /i-Hectane for example, has been made by this method in 60% [Pg.36]

Place a mixture of 0-5 g. of finely powdered thiourea, 0-5 g. of the alkyl halide and 5 ml. of alcohol in a test-tube or small flask equipped with a reflux condenser. Reflux the mixture for a j)eriod depending upon the nature of the halide primary alkyl bromides and iodides, 10-20 minutes (according to the molecular weight) secondary alkyl bromides or iodides, 2-3 hours alkyl chlorides, 3-5 hours polymethy lene dibromides or di-iodides, 20-50 minutes. Then add 0 5 g. of picric acid, boil until a clear solution is obtained, and cool. If no precipitate is obtained, add a few drops of water. RecrystaUise the resulting S-alkyl-iso-thiuronium picrate from alcohol. [Pg.292]

As a practical matter elimination can always be made to occur quantitatively Strong bases especially bulky ones such as tert butoxide ion react even with primary alkyl halides by an E2 process at elevated temperatures The more difficult task is to find condifions fhaf promofe subsfifufion In general fhe besf approach is fo choose condi lions lhal favor fhe 8 2 mechanism—an unhindered subslrale a good nucleophile lhal IS nol slrongly basic and fhe lowesl praclical lemperalure consislenl wilh reasonable reaclion rales [Pg.350]

Rate IS governed by stability of car bocation that is formed in loniza tion step Tertiary alkyl halides can react only by the SnI mechanism they never react by the Sn2 mecha nism (Section 8 9) Rate IS governed by steric effects (crowding in transition state) Methyl and primary alkyl halides can react only by the Sn2 mecha nism they never react by the SnI mechanism (Section 8 6) [Pg.356]

The Williamson ether synthesis (Sec tion 16 6) An alkoxide ion displaces a halide or similar leaving group in an Sn2 reaction The alkyl halide cannot be one that is prone to elimination and so this reaction is limited to methyl and primary alkyl halides There is no limitation on the alkoxide ion that can be used [Pg.693]

Phthalimide with a of 8 3 can be quantitatively converted to its potassium salt with potassium hydroxide The potassium salt of phthalimide has a negatively charged nitrogen atom which acts as a nucleophile toward primary alkyl halides m a bimolecu lar nucleophilic substitution (Sn2) process [Pg.930]

As crowding at the carbon that bears the leaving group decreases the rate of nude ophilic attack by the Lewis base increases A low level of steric hindrance to approach of the nucleophile is one of the special circumstances that permit substitution to pre dominate and primary alkyl halides react with alkoxide bases by an 8 2 mechanism m preference to E2 [Pg.348]

In practice this reaction is difficult to carry out with simple aldehydes and ketones because aldol condensation competes with alkylation Furthermore it is not always possi ble to limit the reaction to the introduction of a single alkyl group The most successful alkylation procedures use p diketones as starting materials Because they are relatively acidic p diketones can be converted quantitatively to their enolate ions by weak bases and do not self condense Ideally the alkyl halide should be a methyl or primary alkyl halide [Pg.781]


See other pages where Primary alkyl is mentioned: [Pg.375]    [Pg.7]    [Pg.152]    [Pg.89]    [Pg.74]    [Pg.75]    [Pg.146]    [Pg.243]    [Pg.335]    [Pg.336]    [Pg.354]    [Pg.383]    [Pg.486]    [Pg.511]    [Pg.617]    [Pg.673]    [Pg.693]    [Pg.784]    [Pg.1291]   


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2,2 -Pyridilic acid with primary alkyl Grignard reagents

Acid-catalyzed reactions with primary or secondary alkyl

Alkyl bromides by reaction of primary alcohols with

Alkyl chlorides, primary

Alkyl derivatives primary alkylamines

Alkyl fluorides primary

Alkyl halides conversion to primary amines

Alkyl halides primary

Alkyl halides, primary, oxidation

Alkyl halides, primary, oxidation carboxylic acids

Alkyl nitrites primary process

Alkyl peroxides, primary photodissociation

Alkyl radical primary

Alkylation at primary and secondary nitrogen

Alkylation indirect, primary amines and

Alkylation of primary amines

Amines N-alkylation by primary alcohols

Benzene, 1,3,5-tribromo with primary alkyl Grignard reagents

Benzene, trichlorodialkylation coupling reactions with primary alkyl Grignard

Benzene, trichlorodialkylation with primary alkyl Grignard reagents

Bicyclic primary alkyl

Bromides, primary alkyl, phosphonate

Buchwald primary alkyl amines and

Carboxylic acids, by oxidation of primary alkyl halides

Cross-coupling reactions primary alkyl

Ester with primary or secondary alkyl

For hydrolysis of ester with primary or secondary alkyl

Grignard reagents primary alkyl

Halides coupling reactions with primary alkyl Grignard

Iodides, primary alkyl, phosphonate

N-Alkylation of primary

N-Alkylation of primary amides

Organotin compounds primary alkyl

Organozinc compounds primary alkyl

Organozinc reagents primary alkyl

Primary Alkyl Cations

Primary alcohols conversion to alkyl halides with

Primary alkyl a-sulfonyl

Primary alkyl alcohol synthesis

Primary alkyl alkylation

Primary alkyl amines

Primary alkyl bromides

Primary alkyl coupling reactions with alkenyl halides

Primary alkyl coupling reactions with aromatic halides

Primary alkyl groups

Primary alkyl halides reactions

Primary alkyl halides synthesis

Primary alkyl halides synthesis from acid chlorides

Primary alkyl halides, in Michaelis-Arbuzov

Primary alkyl halides, in Michaelis-Arbuzov reaction

Primary alkyl halides, oxidation to aldehydes

Primary alkyl iodide

Primary alkyl physical properties

Primary alkyl propargyl

Primary alkyl radical spin trapping

Primary alkyl reactions with alkenyl halides

Primary alkyl reactions with epoxides

Primary alkyl ring opening

Primary alkyl structure

Primary alkyl systems, solvolysis

Primary alkyl tandem vicinal difunctionalization

Primary amines, alkylation

Primary conversion to alkyl halides with

Primary photodissociation of alkyl and

Primary structure reduction and alkylation

Purine, 6-chlorocoupling reactions with primary alkyl Grignard reagents

Purine, 6-methylthiocoupling reactions with primary alkyl Grignard reagents

Rate constants for nucleophilic substitution in primary alkyl substrates

Reductive Alkylation of Primary Amines with Carbonyl Compounds

Reductive N-Alkylation of Primary Amides with Carbonyl Compounds

Tellurophene with primary alkyl Grignard reagents

Tertiary-alkyl primary amines

Transition state to primary alkyl halides

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