The QTAIM is based on the topological analysis of the electron charge density to predict the structure and the stability of a molecular system. That approach allows for the evaluation of various topological parameters at the bond critical points (bcp) to gain insight into the nature and characteristics of chemical bonds. The electron density (b) at the bcp reflects the strength of a bond and its Laplacian (( 2 b) measures the local charge concentration ( 2 b < 0) or local charge depletion ( 2 b > 0). These two properties along with the total energy density (Hb) are used to analyse the covalent character of an interaction. The topological analysis has been used to understand the changes in the breaking and forming bonds of several organic reactions.