Fortunately, tetrone 3b can also be prepared by oxidation of 1,4,5,8-tetramethoxyanthracene 2b (Scheme 2, bottom) using ceric ammonium nitrate (CAN), a reaction that seemed more promising to us despite the reported moderate yield of 45% and the not reported experimental details and characterization results. The required tetramethoxyanthracene 2b can be prepared from 1-bromo-2,5-dimethoxybenzene. The easy accessibility of this precursor certainly is an advantage of this reaction, but the low yield of 32% as well as the need for lithium 2,2,6,6-tetramethylpiperidide (LTMP) as the reagent are disadvantages that have to be considered. We decided to follow a different approach starting from low-cost 1,8dihydroxy-9,10-anthraquinone 1b (Scheme 2, bottom), as this approach was reported to be useful also on a larger scale: