Rate Increase in Consecutive Nucleophilic Aromatic Substitution Reactions of Trichlorotrinitrobenzene:  The Synthesis of 1-(Alkylamino)-3,5-dichloro-2,4,6-trinitrobenzenes

Abstract

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Kinetics and reactivity of substituted anilines with 2‐chloro‐5‐nitropyridine in dimethyl sulfoxide and dimethyl formamide

“…The low negative Δ S # values in DMSO than in DMF indicated that the order of the transition state is sensitive to the change in nature of the solvent; the present reaction involves a neutral nucleophile and a negatively charged leaving group Cl − , therefore there are two different charges on the transition state and hence their solvation energies are different; the transition state is a dipolar one because there is a concomitant development of a delocalized negative charge in the hetarene ring and an sp 3 positively charged nitrogen atom, transition state (I) (Scheme ). The solvation of (I) in DMSO and DMF presumably arises from an ion–dipole interaction suggesting that it is weaker in DMF; and the transition state is more strongly solvated by basic solvents when amines are used as nucleophiles 1–5. …”

“…the transition state is more strongly solvated by basic solvents when amines are used as nucleophiles 1–5.…”

“…Kinetic studies of nucleophilic substitution reactions of activated aromatic substrates with amines have been the subject of many excellent reviews and books 1–6. On the other hand, several investigations have demonstrated a great increase in the reactivity of the anionic nucleophiles in dipolar aprotic solvents due to the increase of the basicity of the base 7–10.…”

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

“…Kinetic studies of nucleophilic substitution reactions of aromatic substrates have been the subject of several excellent reviews and books [1][2][3][4] and are still an area of active research [5][6][7][8][9]. The presence of electron-withdrawing ring substituents such as the nitro group strongly accelerates substitution, and ring nitrogen atoms have also been found to exert a powerful activating effect [7].…”

Simulation, shared spaces, and information management to support discovery and learning: An application in emergency management

“…Kinetic studies of nucleophilic substitution reactions of aromatic substrates have been the subject of several excellent reviews and books 1–4 and are still an area of active research 5–9. The presence of electron‐withdrawing ring substituents such as the nitro group strongly accelerates substitution, and ring nitrogen atoms have also been found to exert a powerful activating effect 7.…”