Computational Characterization of Bidentate P-Donor Ligands: Direct Comparison to Tolman's Electronic Parameters

The applicability of two types of transition-metal carbonyl complexes as appropriate candidates for computationally derived Tolman's ligand electronic parameters were examined with density functional theory (DFT) calculations employing the B97D3 functional. Both Pd⁽⁰⁾L2(CO) and HRh^(I)L2(CO) complexes correlated well with the experimental Tolman Electronic Parameter scale. For direct comparison of the electronic effects of diphosphines with those of monophosphines, the palladium-containing system is recommended. The t r a n s influence of various phosphines did not show a major difference, but the decrease of the H-Rh-P angle from linear can cause a significant change.