Side-on cupric-superoxo triplet complexes as competent agents for H-abstraction relevant to the active site of PHM.

Copper complexes with N3S donors mimic the CuM site of copper monooxygenases and react with O2 affording side-on cupric-superoxo complexes capable of H-abstraction from dihydroanthracene and THF. Spectroscopic and DFT data of the Cu-superoxos support a spin triplet ground state for the side-on complexes, as well as a hemilabile thioether.