1: sodium hydride / tetrahydrofuran; hexamethylphosphoric acid triamide / Ambient temperature 2: tetrahydrofuran; hexamethylphosphoric acid triamide 3: aq. H2SO4 / Ambient temperature 4: aq. H2SO4 / Ambient temperature View Scheme

oxygen; copper acetylacetonate in benzene 1.) reflux, 5 h; 2.) r.t., overnight;

in ethanol 168 h; Ambient temperature;

sodium hydride; p-toluenesulfonyl chloride 1.) THF, HMPA, r. t., 15 min, 2.) 50 deg C; Yield given. Multistep reaction;