DFT Study on the Oxidative Addition of 4-Substituted Iodobenzenes on Pd(0)-Phosphine Complexes

Table 2

Computed activation free energies and reaction free energies (in kcal/mol) for the oxidative addition of 4-substituted iodobenzenes following the dissociated pathway. The opening step that is the dissociation of one trimethylphosphine needs a free energy of 31.2 kcal/mol. Free energy values are relative to the sum of those of Pd(PMe₃)₂ and the corresponding iodobenzenes.

Substituent		Pathway
NMe2	−0.83		3.5	14.6	−10.9
OMe	−0.37		3.0	15.8	−11.3
Me	−0.17	(	5.8	15.5	−11.2
H	0		13.4	14.2	−13.1
Cl	0.23		11.8	13.0	−12.0
CF3	0.54		11.9	12.6	−10.5
CN	0.66		11.0	11.7	−13.0
NO2	0.78		10.6	12.2	−13.6

The gibbs free energy of activation.