• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.373-378
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• 2015

The solvolysis rate constants of di-n-butyl phosphorochloridate ((CH₃CH₂CH₂CH₂O)₂POCI, 1) in 28 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N_T solvent nucleophilicity scale and Y_Cl solvent ionizing scale, with the sensitivities values of 1.40 and 0.42 for l and m, respectively. These l and m values can be considered to support an S_N2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH^≠ (8.0 to 15.9 kcal·mol⁻¹ ) values and large negative ΔS^≠ (−25.8 to −53.1 cal·mol⁻¹ ·K⁻¹ ) values, the Kivinen’s n values (0.9~1.7), and the solvent kinetic isotope effect (1.62).

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.419-424
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• 1987

Kinetic studies on the solvolysis of para-methyl benzyl nitrate and benzyl nitrate were carried out in aqueous methanol, ethanol, acetonitrile, acetone, tetrahydrofuran and dioxane mixtures at 60$^{\circ}$C. The rates were faster in protic solvent mixtures than in aprotic solvent mixtures. This was considered in the light of transition state stabilization by hydrogen bonding solvation of protic solvent mixtures. Grunwald-Winstein equation, extended Grunwald-Winstein equation and correlation between E$_T$(30) and rate constant were applied in order to discuss the transition state variations caused by changing benzyl substituents and solvents. The results showed that strong electrophilic assistance of solvent is operative in the the water-rich solvents.

• Journal of the Korean Chemical Society
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• v.60 no.1
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• pp.16-20
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• 2016

The solvolysis rate constants of biphenyl-4-carbonyl chloride (C₆H₅C₆H₅COCl, 1) in 19 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N_T solvent nucleophilicity scale, Y_Cl solvent ionizing scale, and I aromatic ring parameter with sensitivity values of 0.31±0.10, 0.46±0.05, and 0.96±0.20 for l, m, and h, respectively. These l, m, and h values can be considered to support a dissciative S_N2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH^‡ (15.3~16.1 kcal/mol) values and large negative ΔS^‡ (−17.2~−20.0 cal/mol·K) values.