Synthesis of 2-substituted 9,10-anthraquinones

A convenient preparation of racemic 2-substituted 9,10-anthraquinones that included 2-triazoylethyl skeleton 1 and 2-alkylethyl skeleton 6 is reported. The products were obtained in good yields by a three- or four-step synthetic route based on a sequence of N-bromosuccinimide (NBS)–mediated bromination of 2-ethyl-9,10-anthraquinone 2, nucleophilic substitution, and CuI-catalyzed 1,3-dipolar cycloaddition or alkylation/reductive desulfonylation. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]