Effects of denticity and ligand rigidity on reactivity of copper complexes with cumyl hydroperoxide

[Display omitted] •Syntheses of N-polydentate copper(II) complexes with varied rigidity and denticity.•Reaction with cumyl hydroperoxide generated absorption bands from 380 to 420 nm.•Heterolytic cleavage predominates in the presence of tetradentate copper complexes.•Ligand rigidity has a minor effect on cleavage pathway. Cu(II) complexes bearing N2/Py2 tetradentate ligands consisting of two pyridyl arms and a flexible ethyldiamine backbone, [(BPMEN)Cu(ClO4)2] (1), with rigid cyclohexyl backbone [(BPMCN)Cu(ClO4)2] (2), and substituted with bispyrrolidyl [(PDP)Cu(ClO4)2] (3), and Cu(II) complex bearing N2/Py3 pentadentate ligand, [(TPMEN)Cu(ClO4)2] (4), were synthesized and structurally characterized. Reactivity of 1–4 with cumyl hydroperoxide was investigated to study the effects of ligand rigidity and denticity on the mechanism of O–O bond cleavage. Results presented herein illustrate that 1–3 favors homolysis, however 4 showed little to almost no impact on O–O bond cleavage.