Transforming the naphthalene diimide (NDI) core into unusuala romatics ystems hasl arge potentialf or applicationsi nw hich currentN DI-baseds ystemss how promise. Treatment of N,N-dialkylNDIs under mild oxidizing conditions with ruthenium(III) chloride and sodium periodate affords the corresponding 1,4-diones in good yield. Interestingly,w hilea liphatic substituents at the Nimide positions allowed oxidation to take place easily,t he presence of neutral, electron-rich or electron-deficient phenyl groups retarded the oxidation process under these reaction conditions. The chemistry of the 1,4-dionei st hen explored through reduction and condensation reactions.In two examples, reaction of the 1,4-dione with diamines gives an unusual,r ing-contracted product 20,w hich has ah igh quantumy ield. Additionally,t he 1,4-dione can be converted into larger heterocycles such as 21 and 22 featuring an isoquinoline core. The 1,4-diones and their products have been investigated by spectroscopy,c yclic voltammetry,t heoretical studies, and X-ray crystallography. The results obtained demonstrate the potential of the 1,4dione to serve as an invaluable precursor for NDI-based research.The potentialo fn aphthalened iimides (NDI) and core-substituted naphthalene diimides (cNDI) in organic electronics, [1] as sensors, [2] in DNA binding [3] and detection, [4] and as supramolecular [5] and donor-acceptor motifs [6] means the development of novel systems derived from them offer great scopet o their utility.O xidationr eactions of members of the rylene family,specifically the NDIs, have yet to be explored. Arelevant example of oxidationo fp olyaromatic systems is that of pyrene 1,w hich,u nder mild conditions with ruthenium(III) chloride and sodium periodate, [7] gives the corresponding ketones 2 and 3 in high yield (Scheme 1). [8] We surmised that if NDIs could be oxidized in similar ways, then the potentialt oa nnulate with, for example, aromatic 2,3-diaminesc ould be made to extendt he aromaticity of the naphthalene core, yielding new compounds with different and favourable electronic and photophysical properties. [9] Here, we explore the oxidation of simplea liphatic and aromatic NDIs and extend the chemistry of the products towards new systemsw ith enhanced photophysicalproperties.The NDI precursors 4-12 (Scheme 2) were prepared by treating naphthalene 1,4,5,8-dianhydride with an excess of the corresponding amine in high yield. Oxidation of NDIs 4-8 with two equivalents of ruthenium(III) chloride ands odium periodate at 35 8Cg ave the corresponding diones, 13-17 in good yield. Longer reactiont imes, highero xidant equivalents and Scheme1.Synthesis of pyrene dione 2 and tetraone 3.higher temperatures did not result in further oxidation to produce useful products or improvet he yield.Though the pyrene precedence shown in Scheme 1i ntimates the product should be that of the 2,3-dione, NMR characterization, and in particular 13 CNMR spectroscopy precludes the formationovert he 1,4-dione. [11,12] Interestingly,c ompounds bearing ...