Exploring the catalytic activity of the copper(II) complex of pentadentate ligand in oxidizing o-aminophenol (OAP) has not been extensively studied. To scrutinize the least explored domain, we synthesized and characterized the copper(II) complex of pentadentate ligand, 3-(bis(pyridin-2-ylmethyl)amino)-N-(quinolin-8-yl)propanamide. Further, the complex was allowed to react with OAP to form 2-aminophenoxazin-3-one (APX) via oxidative coupling reaction, the resultant product is a functional analogue of phenoxazinone synthase (PHS), an active enzyme, relevant to the industrial production of a widely recognized antibiotic called Actinomycin D. Furthermore, kinetic studies were performed to comprehend the path of the reaction which unveiled the formation of the complex-substrate adduct. It is worth noticing that the complex displayed an impressive turnover number of 6.4 × 104 h−1 under atmospheric conditions in methanol. To the best of our knowledge, the present complex is the first copper(II) complex with pentadentate N5 ligand showing PHS mimicking catalytic activity.