Figure 74.
Ligand arm steric bulk can be influential for the copper species formed upon oxygenation of copper(I) complexes (THF solvent, −380 °C). The higher steric bulk of −3XR2 disfavors pyridyl ligand binding to Cu upon dimerization, thereby giving tridentate copper coordination, which favors the bis-μ-oxo isomer. See the text.