The mechanistic study of reaction between N-benzoyl carbamates and aliphatic/aromatic amines for synthesis of substituted N-benzoyl urea derivatives: a DFT approach

A thorough investigation on whether a stepwise or a concerted pathway is involved in the synthesis of substituted N-benzoyl urea derivatives by reaction of substituted N-benzoylcarbamates and aliphatic/aromatic amines using density functional theory (DFT) calculations at B3LYP/6-31+G (d,p) level of theory has been reported. The study of effects of nature of leaving group present in N-benzoylcarbamate, structure of amines, and solvents on the reaction showed that the choice of reaction mechanism involved depends upon the nature of leaving group present on N-benzoylcarbamate. The effect of structure of amine on reaction mechanism depends upon the type of leaving group present on N-benzoylcarbamate. We have also observed that the reaction between aliphatic/aromatic amine with phenyl benzoylcarbamate is thermodynamically more favorable, while a reaction between phenyl/methyl benzoylcarbamates with methylamine is more preferred. The effect of polar solvent water and non-polar solvent toluene on reaction mechanism was also investigated to account the interactions of solvent molecules with polar transition states at the same level of theory.