Publications by authors named "Md Ehtesham Ul Hoque"

The nucleophilic substitution reactions of Y-O-aryl methyl phosphonochloridothioates with substituted anilines (XC(6)H(4)NH(2)) and deuterated anilines (XC(6)H(4)ND(2)) are investigated kinetically in acetonitrile at 55.0 degrees C. The Hammett and Brønsted plots for substituent (X) variations in the nucleophiles are biphasic concave downwards with a break region between X = H and 4-Cl.

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The reactions of ethyl Y-phenyl chloro (1) and chlorothio (2) phosphates with X-anilines in acetonitrile at 55.0 degrees C are studied kinetically and theoretically. Kinetic results yield the primary kinetic isotope effects (k(H)/k(D) = 1.

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Kinetic studies of the reactions of aryl phenyl chlorothiophosphates (1) and aryl 4-chlorophenyl chlorothiophosphates (2) with substituted anilines in acetonitrile at 55.0 degrees C are reported. The negative values of the cross-interaction constant rhoXY (rhoXY = -0.

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Synopsis of recent research by authors named "Md Ehtesham Ul Hoque"

  • - Md Ehtesham Ul Hoque's research primarily focuses on the kinetic studies of nucleophilic substitution reactions, particularly involving anilines and phosphonochloridothioates or phosphates, exploring isotope effects in these reactions.
  • - His findings reveal intricate relationships between substituents in the nucleophiles and their reactivity, as observed through biphasic patterns in Hammett and Brønsted plots, indicating the complexity of electronic effects during the reaction mechanisms.
  • - The kinetic mechanisms investigated demonstrate significant primary and secondary isotope effects, alongside theoretical insights, contributing to a deeper understanding of aminolysis processes involving aryl chlorothiophosphates and their behavior under varying conditions.