Quantitative estimation of the α-effect in the reactions yielding phosphorus-containing thiosemicarbazides
作者:N. I. Yanchuk
DOI:10.1134/s1070363206080111
日期:2006.8
The alpha-effect in the reactions of O,O-diaryl phosphorohydrazidothioates with phenyl isothiocyanate in benzene at 25 degrees C was quantitatively evaluated from the kinetic data. The probable reaction mechanism was suggested, and the causes of the alpha-effect in these reactions are discussed. An approximate linear correlation is observed between the alpha-effect in the reactions of O,O-diaryl phosphorohydrazidothioates with phenyl isothiocyanate, basicity constants of the hydrazides, and sigma(P) constants of the substituents at the P atom. The value of the alpha-effect is largely determined by the structure of the transition state.