Mimicking the Cu Active Site of Lytic Polysaccharide Monooxygenase Using Monoanionic Tridentate N‑Donor Ligands

In an effort to prepare small molecule mimics of the active site of lytic polysaccharide monooxygenase (LPMO), three monoanionic tridentate N donor ligands comprising a central deprotonated amide group flanked by two neutral donors were prepared, and their coordination chemistry with Cu­(I) and Cu­(II) was evaluated. With Cu­(I), a dimer formed, which was characterized by X-ray crystallography and NMR spectroscopy. A variety of mononuclear and dinuclear Cu­(II) species with a range of auxiliary ligands (MeCN, Cl–, OH–, OAc–, OBz–, CO32–) were prepared and characterized by X-ray diffraction and various spectroscopies (UV–vis, EPR). The complexes exhibit structural similarities to the LPMO active site.