1: With potassium tert-butylate in tetrahydrofuran T=20°C; 0.0833333 h; 2: With 3,3-dimethyldioxirane in tetrahydrofuran; acetone T=20°C; 0.0833333 h; Further stages.;

potassium carbonate; 18-crown-6 ether in acetonitrile T=80°C; 2 h;

sodium hydride DMF, 1.) 30 min, 2.) 30 min; Yield given. Multistep reaction;