The reaction of 2‐phenoxy‐3,5‐dinitropyridine with substituted anilines in the presence of 1,4‐diazabicyclo[2.2.2]octane in dimethyl sulfoxide: Kinetic and equilibrium studies

Abstract

The reactions of 2-phenoxy-3,5-dinitropyridine (1) with a series of substituted anilines (4a-d) in dimethyl sulfoxide (DMSO) in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) yield the 2-anilino derivatives without the accumulation of intermediates. The kinetics is compatible with a two-step reaction involving initial nucleophilic attack followed by either base-catalyzed or uncatalyzed conversion to the product. The base-catalyzed pathway is likely to involve rate-limiting proton transfer from the zwitterionic intermediate to base. The results are compared with those for reactions of 1,3,5-trinitrobenzene (2) and phenyl 2,4,6-trinitrophenyl ether (3, R = Ph) with anilines.

Study of Kinetics, Equilibrium and the Influence of Steric Effects on Proton‐Transfer in the Reactions of 2, 2, 4‐ and 2, 6‐ Substituted Anilines with 2‐Phenoxy‐3,5‐dinitropyridine in DMSO

“…More recently, kinetic and equilibrium results have been reported for the reactions of 2phenoxy-3,5-dinitropyridine (1), with some 4-substituted anilines in the presence of DABCO, in DMSO 17 .…”

“…It is known that reaction at unsubstituted ring positions to give anionic adducts may precede the attack at the 2-positon [15][16][17][18][20][21] . Previous work [10][11][12][13][14][15][16][17][18][20][21][22] , at lower base concentrations and in different solvents did not find evidence for base catalysis. However, the present work shows that in DMSO such catalysis occurs and the values of K 1 k An and K 1 k DABCO for reactions of 1 with anilines are calculated.…”

Kinetic studies of reactions of 4‐nitrobenzofuroxan with carbanions derived from benzyltriflones in methanol

“…In another study, the results of kinetic measurements of the reactions of carbanions derived from ring‐substituted benzyltriflone anions, 3a–e , and nitrogen nucleophile with nitrobenzofurazan derivatives, in methanol and DMSO, respectively, were studied 20–30 to obtain a comparison of these results with the previous results obtained with 4‐nitrobenzofuroxan.…”