34749-63-8Relevant articles and documents
Electronic and steric effects in the SNAr substitution reactions of substituted anilines with 2,4-dinitrophenyl 2,4,6-trinitrophenyl ether in acetonitrile
Crampton, Michael R.,Emokpae, Thomas A.,Isanbo, Chukwuemeka
, p. 75 - 80 (2007/10/03)
Rate measurements are reported for the reactions of 12 ring-substituted anilines with 2,4-dinitrophenyl 2,4,6-trinitrophenyl ether (1) in acetonitrile. Formation of the products, the correspondingly substituted 2,4,6- trinitrodiphenylamines, occurs without the observation of intermediates in detectable amounts by both base-catalysed and uncatalysed pathways and Hammett ρ value were determined for these processes. The results show that although substituents at the 3- or 4-positions of the anilines have only small steric effects, alkyl substituents at the 2-position may result in considerable reductions in reactivity. These effects are more pronounced for the base-catalysed pathway and in 2,6-dimethylaniline the uncatalysed pathway takes all the reaction flux. In the case of the 2-fluoro substituent the electronic effect, strong inductive electron withdrawal, is dominant over steric effects. Copyright
Mechanism of the Reactions of Substituted Anilines with Phenyl 2,4,6-Trinitrophenyl Ether in Benzene: Evidence for a Cyclic Transition State involving an Eight-membered Ring
Banjoko, Olayinka,Ezeani, Chike
, p. 1357 - 1360 (2007/10/02)
Rates and activation parameters have been determined for the reactions of phenyl 2,4,6-trinitrophenyl ether with substituted anilines in benzene.For some of the nucleophiles, the rates decrease with increasing temperature in the range 5-35 deg C resulting in negative activation enthalpies (ΔH(excit.) -3.1 to -27.3 kJ mol-1).This is strong evidence for a stepwise mechanism involving (at least) a pre-equilibrium.These base-catalysed nucleophilic substitution reactions are sensitive to the nature of the arylated amine as indicated by the Hammett's constant (ρ -7.7).
