Comparing the impact of different supporting ligands on copper(I)-ethylene interactions

作者：Geri Jacob B; Pernicone Naomi C; York John T^*

来源：Polyhedron, 2013, 52: 207-215.

DOI：10.1016/j.poly.2012.09.046

• Copper
• Ethylene
• Density functional theory
• N-donor ligands

The nature of copper(I)-ethylene bonding in a series of [Cu(L)(C2H2)](n+) complexes (where L = 1,4,7-trithiacyclononane, 2,2'-bipyridine, N,N,N',N'-tetramethylethylenediamine, 1,4,7-trimethyl-1,4,7-triazacyclononane, hydrotris(3,5-dimethyl-1-pyrazolyl)borate, the bis(2,6-dimethylphenyl)-substituted beta-diketiminate, and the iminophosphanamide (tBu)(2)P(NSiMe3)(2)) has been studied using density functional theory methods. The B3LYP, M06-L, and BP86 functionals performed similarly in reproducing important geometric parameters from experimental structures. Bonding interactions between the [Cu(L)](n+) and ethylene fragments were investigated using energy decomposition analysis (ALMO-EDA), molecular orbital and fragment orbital interaction analysis, and natural bond orbital (NBO) analysis. NBO and EDA calculations both predict an increase in [Cu(L)](n+) -> ethylene(pi*) charge donation and stabilization with an increase in the qualitatively-predicted electron donating ability of the supporting ligand, and a lesser amount of ethylene(pi) -> Cu charge donation, the magnitude of which is not strongly correlated to ligand donor ability. Molecular orbital analysis reveals an increased mixing of the empty ethylene pi*-orbital with filled orbitals as the qualitative ligand donating ability increases, consistent with enhanced Cu -> ethylene(pi) pi-backbonding and the NBO and EDA results.

• 出版日期2013-3-22