On the theoretical side, both Deeth et al. , Bäcktorp and Norrby, and Domzalska-Pieczykolan et al. have explained experimentally observed regioselectivity based on DFTcomputed barrier heights of the insertion step. Deeth et al. have developed a predictive model based on DFT-computed electrostatic and orbital properties of the neutral or cationic alkene-catalyst complexes which they test on eight different alkenes. They use a very simplified model of the Pd catalyst (PdIPH 3 and Pd(PH 3 ) 2 for the neutral and cationic pathway, respectively) and the aryl group is replaced by ethene, but still they get a good agreement with the experimentally observed regioselectivities.