Investigation of the electron density of iridium(I) Vaska-type complexes using DFT calculations and structural results: Structure of trans-carbonyl-chloro-bis(tricyclohexylphosphine)-iridium(I)

[Ir(CO)Cl(PCy3)2] was obtained by the slow attack of 1,2-dichloromethane on (Bu4N)[Ir2(μ-Dcbp)(CO)2(PCy3)2] (Dcbp = 3,5-dicarboxylatepyrazole). The Ir–CO, Ir–Cl and Ir–P bond distances are 1.778(10), 2.374(3) and 2.3486(8) Å, respectively. The Ir–P bond distances for a number of different Vaska complexes indicate the shortest bond distances for phoshines containing electron withdrawing groups. An excellent correlation between DFT (OLYP/ZORA/TZP) and experimental structures is obtained as reflected by the RMSD values (H excluded) of between 0.083 and 0.268 Å for the different complexes studied. The calculated Ir–P bond distances and ν(CO) stretching frequencies closely follow the trends obtained from the experimental results.

DFT calculations on a number of different iridium Vaska complexes indicated an excellent correlation between experimental and theoretical structures is obtained as reflected by the RMSD values (H excluded) of between 0.083 and 0.268 Å. The calculated Ir–P and ν(CO) closely follows the trends obtained from the experimental results.Figure optionsDownload as PowerPoint slide