CC BY-NC 4.0 UnportedTaeufer, TobiasArgüello Cordero, Miguel A.Petrosyan, AndranikSurkus, Annette‐E.Lochbrunner, StefanPospech, Jola2022-01-142022-01-142021https://oa.tib.eu/renate/handle/123456789/7810https://doi.org/10.34657/6851Herein we describe the synthesis and photophysical and electrochemical characterization of pyrimidopteridine-based photoredox catalysts. The pyrimidopteridines can be obtained from the corresponding N-oxides through photo-mediated oxygen atom transfer to a sacrificial acceptor molecule on gramscale. The presence of a triplet excited state was evidenced by means of transient absorption spectroscopy. Pyrimidopteridines are potent excited state oxidants with excited state reduction potentials exceeding +2.10 V vs. SCE in MeCN. The catalytic activity is illustrated in the photo-mediated oxidative annulation of 2-phenylbenzoic acid.enghttps://creativecommons.org/licenses/by-nc/4.0/540deoxygenationheteroarenesN-oxidesorganic photoredox catalysispyrimidopteridinesArticle