Complexity with simplicity: a steric continuum of chelating diamines with copper(I) and dioxygen

Copper(I) complexed by simple peralkylated diamines reacts with O2 at low temperature in aprotic solvents to create a diverse set of thermally sensitive, polynuclear copper products. Structural and spectroscopic characterization of several complexes provides keen insights into the complexity of this ostensibly simple, yet important, biological and industrial reaction. A correlation of a series of closely related copper(I) complexes with their oxygenated products highlights the preeminent, though not absolute, role of the ligand in these multi-step formation reactions. A steric continuum of diamine ligands provides a sensitive probe into this copper(I)/O2 reactivity. The diverse product distribution is interpreted through a single unifying mechanism.