The reaction of 2,4-dinitrofluorobenzene with aniline, cyclohexylamine, and 1,2-diaminocyclohexanes in aprotic solvents. A new approach to the ‘dimer mechanism’

doi:10.1039/P29900001073

Paper

The reaction of 2,4-dinitrofluorobenzene with aniline, cyclohexylamine, and 1,2-diaminocyclohexanes in aprotic solvents. A new approach to the ‘dimer mechanism’

Published 1990 · N. Nudelman, J. Montserrat

Journal of The Chemical Society-perkin Transactions 1

UNKNOWN SJR score

13

Citations

0

Influential Citations

Full textSemantic Scholar

Abstract

The reaction of 2,4-dinitrofluorobenzene (DNF) with aniline in toluene and in chloroform at 35 °C shows a third-order kinetic dependence on [amine]. In hydrogen-bond acceptor (HBA) solvents, an important rate increase, and a second-order dependence on [amine], are observed. Finally, the reaction shows a second-order dependence on non-nucleophilic tertiary amines. All these results are fully consistent with the previously proposed ‘dioner nucleophile mechanism.’Another approach towards confirming the mechanism was designed: a system where an ‘intramolecular dimer nucleophile’ is possible. The reactions of DNF with cyclohexylamine, and with cis-and trans-1,2-diaminocyclohexane, were studied in toluene, and also in toluene–methanol mixtures in some cases. The kinetic order observed, as well as the enhanced reactivity of the cis isomer and the solvent effects are new evidence in favour of the ‘dimer nucleophile’ mechanism. The results cannot be explained by other, alternative mechanisms.

Study Snapshot

The 'dimer nucleophile' mechanism is supported by the observed kinetic order, enhanced reactivity of the cis isomer, and solvent effects in the reactions of 2,4-dinitrofluorobenzene with aniline, cyclohexylamine, and 1,2-d

PopulationOlder adults (50-71 years)

Sample size24

MethodsObservational

OutcomesBody Mass Index projections

ResultsSocial networks mitigate obesity in older groups.

Sign up to use Study Snapshot

Consensus is limited without an account. Create an account or sign in to get more searches and use the Study Snapshot.

Create an account

Paper

The reaction of 2,4-dinitrofluorobenzene with aniline, cyclohexylamine, and 1,2-diaminocyclohexanes in aprotic solvents. A new approach to the ‘dimer mechanism’

Sign up to use Study Snapshot

References

Solvent effects on aromatic nucleophilic substitutions. Part 3. The kinetics of the reaction of 2,4-dinitrochlorobenzene with piperidine in aprotic solvents

The ET(30) parameter is the most useful measure of solvent influence in the kinetics of the reaction between 2,4-dinitrochlorobenzene and piperidine, with hydrogen-bond acceptor solvents showing the best correlation.

Base Catalysis of Aromatic Nucleophilic Substitution Reactions in Aprotic and Dipolar Aprotic Solvents

Base catalysis of aromatic nucleophilic substitution reactions in benzene occurs regardless of the catalyst's strength, while in acetonitrile, only strong catalysts are observed.

The ‘dimer mechanism’ in aromatic nucleophilic substitution by amines in aprotic solvents

The dimer mechanism proposes a possible mechanism for aromatic nucleophilic substitution by amines in aprotic solvents, explaining fourth-order kinetics and other observed phenomena.

Catalysis of nucleophilic aromatic substitution reactions in mixed solvents. Part 1. Reaction of phenyl 2,4,6-trinitrophenyl ether with aniline in benezene–methanol mixtures: strong evidence against the ‘dimer’ mechanism

The dimer mechanism fails to explain the continuous increase in rate of phenyl 2,4,6-trinitrophenyl ether with aniline in benzene-methanol mixtures, suggesting a single catalysing entity in a cyclic transition state.

Reactions of nitroanisoles. Part 6. Reaction of 2,6-dinitroanisole with cyclohexylamine in mixed solvents. Solvent evidence for the ‘dimer’ mechanism

The reaction of 2,6-dinitroanisole with cyclohexylamine in mixed solvents shows evidence for the 'dimer' mechanism, with a minimum rate at 30% methanol and a linear increase with methanol content.

Citations

Hydrogen-bonded nucleophile effects in ANS: the reactions of 1-chloro and 1-fluoro-2,4-dinitrobenzene with 2-guanidinobenzimidazole, 1-(2-aminoethyl)piperidine and N-(3-aminopropyl)morpholine in aprotic solvents

Hydrogen-bonded nucleophile effects in aprotic solvents can significantly increase reaction rates, with 2-GB in toluene showing intramolecular H-bonding and 3-APMo acting as a better nucleophile than the monomer.

The “dimer nucleophile mechanism” for reactions with rate-determining first step: Derivation of the whole kinetic law and further treatment of kinetic results

The "dimer nucleophile mechanism" is well established in aromatic nucleophilic substitutions by amines in aprotic solvents, as demonstrated by the results of 2,4-dinitrofluorobenzene and 2,4-dinitrochlorobenzene with aniline and alky

SNAr Reactions of Amines in Aprotic Solvents

SNAr reactions of amines in aprotic solvents show both classical and anomalous kinetics, with nucleophile influence and polarizability playing key roles in these reactions.

Hydrogen Bonding and Complex Formation Involving Compounds with Amino, Nitroso and Nitro Groups

Hydrogen bonding and complex formation in compounds with amino, nitroso, and nitro groups can form covalent complexes and non-covalent interactions between amines and nitro aromatic derivatives.

Hydrogen bonding in aromatic polyamine 2-guanidinobenzimidazole: Study based on density functional theory calculations

2-guanidinobenzimidazole exhibits intra- and intermolecular hydrogen bond formation, leading to homo 2-GB and mixed solute-solvent dimers, with the latter being slightly more energetically favorable.

Catalytic effects of hydrogen-bond acceptor solvent on nucleophilic aromatic substitution reactions in non-polar aprotic solvent : reactions of phenyl 2,4,6-trinitrophenyl ether with amines in benzene-acetonitrile mixtures

Acetonitrile addition to benzene-acetonitrile mixtures increases the rate of nucleophilic aromatic substitution reactions with aniline and cyclohexylamine, suggesting a potential role for non-nucleophilic amines.

Role of hydrogen‐bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. reactions of halonitrobenzenes with ethylenediamine, 3‐dimethylamino‐1‐propylamine and histamine in toluene

Hydrogen-bonded nucleophiles play a crucial role in aromatic nucleophilic substitutions in aprotic solvents, with amine homo-aggregates being better nucleophiles than amine monomers.

Basicity of some phosphines in THF.

The pKa value for tribenzylphosphine is reasonable, but the Fuoss equation for dissociation of ion pairs has limitations.

Rationalization of the conflicting effects of hydrogen bond donor solvent on nucleophilic aromatic substitution reactions in non-polar aprotic solvent: reactions of phenyl 2,4,6-trinitrophenyl ether with primary and secondary amines in benzene-methanol mixtures

Hydrogen-bond donor solvent methanol can cause rate diminution and increase in nucleophilic aromatic substitution reactions, challenging the idea of a 'dimer nucleophile' in these reactions.