• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4387-4391
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• 2011

The kinetic studies on the pyridinolysis of diisopropyl thiophosphinic chloride have been carried out in acetonitrile at $55.0^{\circ}C$. The free energy correlations for substituent X variations in the X-pyridines are biphasic concave upwards with a break point at X = 3-Ph. A concerted SN2 mechanism is proposed with a change of the attacking direction of the X-pyridine from a frontside attack for the strongly basic pyridines to a backside attack for the weakly basic pyridines. The factors to determine the rates and thio effects on the rates for the pyridinolyses of thiophophinic chloride, chlorothiophosphate, phosphinic chloride, phosphonochloridothioate, and chlorophosphate systems are briefly reviewed on the basis of the magnitude of the positive charge of the reaction center P atom and steric effects of the two ligands.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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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.