Theoretical prediction of rate constant of some N-phenylacetamide substitutes reactions with chloramine-T using ab-initio and statistical calculations

Abstract

The rate of constant of N-phenylacetamide substitutes reaction with Chloramine-T have been investigated in this work using ab-initio and statistical calculations. The first order reaction between N-phenylacetamide substitutes and Chloramine-T shows that the rate constant depends on concentration of the N-phenylacetamide substitutes. Therefore, ab initio calculations were applied on the N-phenylacetamide substitutes using DFT/ b3lyp with aug-cc-putz as a basis set, to extract the values of several physical variables such as, mulliken charge at the active atoms, dipole moment, Homo and Lomo energy levels, Hardness (η), Chemical Electronic Potential (μ) and Global Electrophilicity Index (W). The relationship between these physical variables that play an effective role in the reaction rate then found using statistical calculation. These relationships can be found through the investigation of the value of correlation coefficient (R2) and the Standard error (SE). The factors were studied by simple regression analysis and multiple regression analysis between these physical variables as independent variables and rate constant as dependent variable using SPSS software. The high value of R2 (≈1) and SE (≈ zero) of the regression analysis reflect the high relationship between these variables that affect the reaction rate. Finally, the differences between the experimental and calculated rate of constant value were found in about 0.02.