An Approach in Synthesis of 1-Morpholino-2-phenylethane-1,2-dione Catalyzed by Copper (II) Bromide
Abstract
A novel approach towards synthesis of α-Ketoamides was serendipitously found in acetophenone's reaction with a secondary amine catalyzed by copper (II) bromide. This methodology is a promising simple alternative to access biologically active compounds containing α-Ketoamides. Reactions were carried out at room temperature using dimethyl sulfoxide (DMSO) as solvent and catalyst loading at 10 mol %. The products were purified using a chromatographic method and analyzed extensively by spectroscopic methods, namely 1D (1H and 13C) and 2D NMR (HMBC and HSQC). The reaction of acetophenone and morpholine furnished a yield of 6%. Acetophenone derivatives bearing benzyl and acetyl groups were prepared from para-hydroxy acetophenone with 25% and 99% yields, respectively. The products were analyzed by spectroscopic method, namely 1H and 13C NMR. The presence of substituents, namely hydroxyl, benzyl, acetyl group, prevent the formation of α-Ketoamides. Formation of α-Ketoamides in this reaction condition was proposed as the result of the oxidation product in the catalytic cycle of Cu (II).
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