• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1410-1414
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• 2005

Neopentyl arenesulfonates reacted with primary alkylmagnesium halides in the presence of $(PPh_3)_2NiCl_2$ to produce the corresponding alkylarenes. The efficiency of this coupling reaction considerably depends on the nature of catalyst and solvent. Highest yield was obtained by using three equivalents of Grignard reagent to a mixture of $(PPh_3)_2NiCl_2$ and arenesulfonate in refluxing $Et_2O$. This reaction represents a novel method allowing the efficient and creative substitution of sulfur-containing groups in aromatic compounds. It also shows that the alkyloxysulfonyl group might be a suitable alternative to halides and triflate in some circumstances.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.281-284
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• 2007

Neopentyl arenesulfonates react with secondary alkylmagnesium chlorides in the presence of dppfNiCl2 to produce the corresponding arenes via the reductive cleavage of carbon-sulfur bond. Highest yield is obtained by using three equivalents of Grignard reagent to a mixture of arenesulfonate and dppfNiCl2 in Et2O at room temperature. This reaction represents a novel method allowing the efficient hydrogenolysis of sulfur-containing groups in aromatic compounds.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.254-257
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• 1996

Nucleophilic substitution reactions of 1- and 2-naphthylethyl arenesulfonates, 2 and 3, with anilines and benzylamines in methanol at 65.0 ℃ are investigated. The rates are slower than those for the corresponding derivatives of 2-phenylethyl arenesulfonates, 1, which can be attributed to a greater degree of positive charge stabilization at Cα in the transition state (TS) by a greater electron supply from a phenyl ring compared to a naphthyl ring. The mechanism for the two naphthylethyl systems are similar to that for the 2-phenylethyl derivatives, except that the transition state is formed at somewhat an earlier position along the reaction coordinate. The secondary kinetic isotope effects involving deuterated nucleophilies indicate that naphthylethyl series are sterically more crowded in the TS than 2-phenylethyl system. The data in this work can not elucidate the possible participation of the aryl-assisted pathway in the reaction.

• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1334-1336
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• 1998

Kinetic studies are carried out on the reactions of 2-chloro-2-propen-1-yl arenesulfonates with anilines and N,N-dimethylanilines in acetonitrilile at 45.0 ℃. The 2-chloro substituent is found to deactive the allyl moiety with considerable decrease in the rates. The sign and magnitude of the cross-interaction constant (ρxz 0.3) and the inverse secondary kinetic isotope effect (kH/kD 0.92) support an SN2 mechanism with a relatively tight transition state. The possibility of an SN2' mechanism can be safely precluded based on the ρxz values observed.

• Journal of the Korean Chemical Society
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• v.19 no.2
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• pp.116-122
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• 1975

Determination has been made of the kinetics of the reaction of benzyl arenesulfonates with pyridine in acetone. The substituent effects of the leaving groups in benzyl arenesulfonates are correlated by Hammett equations, with the exception of p-MeO and $p-NO_2$ groups, where the electron attracting substituents in the benzyl arenesulfonate increase the rate. The substituent effects of the leaving groups are as expected due to the nucleophilic attack of amine on the benzyl carbon atom. This can be understood in terms of changes in bond formation (C-N) and bond breaking (C-O) in the transition state with charges in electron-attracting ability of the substituents. The predicted substituent effects may indicate a small increase in bond formation and thus a tighter transition state, in benzyl p-bromobenzene sulfonate than in benzyl p-nitrobenzenesulfonate. Predicting made by Thornton concerning the substituent effects on $S_N2$ transition state structures agrees with the changes in bond formation and bond breaking.

• Bulletin of the Korean Chemical Society
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• v.16 no.8
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• pp.760-763
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• 1995

• Journal of the Korean Chemical Society
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• v.19 no.4
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• pp.240-245
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• 1975

Substituent effects of benzyl substrates for the reaction of substituted benzyl(Z) arenesulfonate(X) with dimethylanilines in (Y) acetone at $35^{circ}$ were studied. The interactions between Z and Y disappeared when changed from electron withdrawing group to releasing group in benzyl substrates. The disappearance of interactions between Z and Y infers change of mechanism from $S_N2 to S_N1$ in substituent Z.

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.827-831
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• 1995

Kinetic studies on the reactions of five secondary acylic alkyl arenesulfonates with anilines are carried out in acetonitrile at 65.0 ℃. The magnitude of ρXZ determined (ρXZ=0.12-0.13) is slightly greater than that for the alicyclic series (ρXZ=0.11) under the same experimental condition. Ab initio MO results are found to support the slightly tighter transition state expected from the greater magnitude of ρXZ for the acyclic series. Despite the small variations, the magnitude of ρXZ and the theoretical transition state tightness remain relatively constant for the secondary carbon centers. Secondary kinetic isotope effects involving deuterated aniline nucleophiles show a successively smaller kH/kD(<1.0) value for a more sterically crowded reaction center carbon. This is in accord with the later transition state for bond-making predicted by the Bell-Evans-Polanyi principle for the more endothermic nucleophilic substitution reaction. Further support is provided by the results of the AM1 MO calculations on the reactions of secondary alkyl benzenesulfonates with chloride nucleophile.

• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.502-506
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• 1994

The results of kinetic studies on the reactions of 2-phenyl-l-propyl arenesulfonates with anilines and benzylamines in methanol at $55.0^{\circ}C$ are reported. The transition state variation with the substituents in the nucleophile (X) and leaving group (Z) is in accord with that expected from a negative ${\sigma}_{XZ}$ value. A stronger nucleophile and nucleofuge lead to a greater extent of bond-making and -breaking. Somewhat greater magnitude of ${\sigma}_{XZ}$ compared to the nearly constant value for the similar processes at a primary carbon atom has been interpreted to result from a partial contribution of the concurrent frontal displacement path.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.161-164
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• 1997

Kinetic studies are carried out on the reactions of 1- and 2-naphthylmethyl arenesulfonates with anilines in acetonitrile at 25.0 ℃. The rates are faster for the 2-naphthylmethyl series than for the corresponding 1-naphthylmethyl series suggesting that there is a greater stabilization of positive charge development in the TS at the arylmethyl reaction center carbon for the former. The sign and magnitude of ρxz (=-0.12) are similar to those of the benzylic series. Thus, benzyl, 1- and 2-naphthylmethyl derivatives belong to a class of compounds which react with aniline nucleophiles through a relatively loose SN2 TS. Kinetic secondary deuterium isotope effects indicated that a stronger nucleophile and nucleofuge lead to a later TS as the definition of ρxz requires.