hydrogen; palladium on activated charcoal in ethyl acetate 4 h;

1: 85 percent / imidazole / dimethylformamide / 24 h / Ambient temperature 2: 83 percent / triethylamine, 4-(N,N-dimethylamino)pyridine / CH2Cl2 / 5 h / -15 - 23 °C 3: 75 percent / sodium hydride / tetrahydrofuran / 3 h / Ambient temperature 4: 99 percent / hydrogen / Pd/C / ethyl acetate / 4 h View Scheme

1: 85 percent / imidazole / dimethylformamide / 24 h / Ambient temperature 2: 83 percent / triethylamine, 4-(N,N-dimethylamino)pyridine / CH2Cl2 / 5 h / -15 - 23 °C 3: 75 percent / sodium hydride / tetrahydrofuran / 3 h / Ambient temperature 4: 99 percent / hydrogen / Pd/C / ethyl acetate / 4 h View Scheme

1: 83 percent / triethylamine, 4-(N,N-dimethylamino)pyridine / CH2Cl2 / 5 h / -15 - 23 °C 2: 75 percent / sodium hydride / tetrahydrofuran / 3 h / Ambient temperature 3: 99 percent / hydrogen / Pd/C / ethyl acetate / 4 h View Scheme

1: 75 percent / sodium hydride / tetrahydrofuran / 3 h / Ambient temperature 2: 99 percent / hydrogen / Pd/C / ethyl acetate / 4 h View Scheme

1H-imidazole in N,N-dimethyl-formamide T=20°C;

potassium hydrogensulfate in methanol T=20°C; 1.5 h;

1: 83 percent / tetrabutylammonium fluoride monohydrate / tetrahydrofuran / 1 h / Ambient temperature 2: 81 percent / pyridinium dichromate / dimethylformamide / 24 h 3: 69 percent / potassium hydrogen carbonate / dimethylformamide / 24 h View Scheme

1: 83 percent / tetrabutylammonium fluoride monohydrate / tetrahydrofuran / 1 h / Ambient temperature 2: 81 percent / pyridinium dichromate / dimethylformamide / 24 h View Scheme