• Title/Summary/Keyword: Anilinolysis

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Kinetics and Mechanism of the Anilinolysis of Diisopropyl Thiophosphinic Chloride in Acetonitrile

  • Ul Hoque, Md. Ehtesham;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.11
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    • pp.3880-3886
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    • 2011
  • The nucleophilic substitution reactions of diisopropyl thiophophinic chloride (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $65.0^{\circ}C$. The anilinolysis rate of 3 is rather slow to be rationalized by the conventional stereoelectronic effects. The obtained deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are secondary inverse ($k_H/k_D$ = 0.80-0.96). The anilinolyses of ten P=S systems in MeCN are reviewed on the basis of DKIEs and selectivity parameters to obtain systematic information on the DKIEs and mechanism for thiophosphoryl transfer reactions. The steric effects of the two ligands on reactivity, DKIEs, mechanism, and substituent effects of the nucleophile (X) on the DKIEs are discussed.

Kinetics and Mechanism of the Anilinolysis of Dibutyl Chlorothiophosphate in Acetonitrile

  • Hoque, Md. Ehtesham Ul;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.843-847
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    • 2012
  • The nucleophilic substitution reactions of dibutyl chlorothiophosphate (4S) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $55.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs;$k_H/k_D$) are primary normal ($k_H/k_D$ = 1.10-1.35). A concerted mechanism involving predominant frontside nucleophilic attack is proposed on the basis of the primary normal DKIEs and selectivity parameters. Hydrogen bonded, four-center-type transition state is proposed. The steric effects of the two ligands on the anilinolysis rates of the chlorothiophosphates are discussed. The anilinolyses of P=S systems are compared with those of their P=O counterparts on the basis of the reactivities, thio effects, selectivity parameters, and DKIEs.

Kinetics and Mechanism of the Anilinolysis of Diisopropyl Chlorophosphate in Acetonitrile

  • Hoque, Md. Ehtesham Ul;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3245-3250
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    • 2011
  • The nucleophilic substitution reactions of diisopropyl chlorophosphate (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $55.0^{\circ}C$. The anilinolysis rate of 3 is rather slow to be rationalized by the conventional stereoelectronic effects. The obtained deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are secondary inverse ($k_H/k_D$ = 0.71-0.95) with maximum magnitude at X = H.A concerted mechanism involving predominant backside nucleophilic attack is proposed on the basis of the secondary inverse DKIEs.

Kinetics and Mechanism of the Anilinolysis of Dipropyl Chlorothiophosphate in Acetonitrile

  • Hoque, Md. Ehtesham Ul;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4403-4407
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    • 2011
  • The nucleophilic substitution reactions of dipropyl chlorothiophosphate (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $55.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are primary normal ($k_H/k_D$ = 1.11-1.35). A concerted mechanism involving predominant frontside nucleophilic attack is proposed on the basis of the primary normal DKIEs and selectivity parameters. Hydrogen bonded, four-center-type transition state is proposed. The steric effects of the two ligands on the anilinolysis rates of various substrates are discussed.

Kinetics and Mechanism of the Anilinolysis of Aryl N,N-Dimethyl Phosphoroamidochloridates in Acetonitrile

  • Barai, Hasi Rani;Lee, Hai Whang
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.753-757
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    • 2014
  • The nucleophilic substitution reactions of Y-aryl N,N-dimethyl phosphoroamidochloridates with substituted anilines and deuterated anilines are kinetically investigated in acetonitrile at $65.0^{\circ}C$. A stepwise mechanism with a rate-limiting leaving group departure from the intermediate is proposed based on the positive ${\rho}_{XY}$ value. The deuterium kinetic isotope effects involving deuterated anilines show secondary inverse with all the nucleophiles, rationalized by a dominant backside nucleophilic attack.