Linear free energy relationships for dechlorination of aromatic chlorides by Pd/Fe

Reductive dechlorination rate constants for five chlorobenzenes in the presence of Pd/Fe as catalyst were determined experimentally. Linear free energy relationships (LFER) for the dechlorination rate constants of five chlorobenzenes and three chlorophenols were developed by partial least squares (PLS) regression based on quantum chemical parameters computed by PM3 Hamiltonian. The optimal LFER model obtained isimagelogk=−1.63+1.46×10−3ΔHf−7.69×10−1ELUMOwhere k stands for the dechlorination rate constants, ΔHf is the standard heat of formation, and ELUMO is the energy of the lowest unoccupied molecular orbital. The Q2cum value of the model is 0.879, indicating good robustness and predictive power of the model.