In present study we employed the method to determine certain thermodynamic descriptors, transition states, global reactivity Indicatorlike the energies of the highest occupied and lowest unoccupied molecular orbitals ( , respectively), the difference between the two( ) gaps, electronic chemical potential μ, chemical hardness η, global electrophilicity index η and global nucleophilicity index N, and local reactivity like the electrophilic and nucleophilic Parr functions, as the most relevant indices forof the reaction between bromotrichloromethane and triethylphosphite . In vibrational frequencies calculation, no imaginary frequency was shown Our results show that triethylphosphite behaves as a nucleophile, while bromotrichloromethane behaves as an electrophile. The nucleophilic attack takes place preferentially at the halogen(Br or Cl) atom of the bromotrichloromethane rather than at the carbon atom. The reaction is exothermic, polar and regioselective. These results are comparable to those obtained experimentally.
