sulfuric acid; nitrogen in sodium hydroxide; chloroform

hydrogen; palladium on activated charcoal in N,N-dimethyl-formamide

perchloric acid 48 h; Ambient temperature;

water; sodium acetate T=50°C; pH=4.9; 25 h; Conversion of starting material;

1: triethylamine / dichloromethane / 1 h 2: trifluoroacetic acid / dichloromethane / 20 °C View Scheme

1: 52 percent / N-methylmorpholine, 1-hydroxybenzotriazole (HOBt), 1-<3-(dimethylamino)propyl>-3-ethylcarbodiimide hydrochloride (EDC) / tetrahydrofuran / 1.) 0 deg C, 1 h, 2.) RT, overnight 2: 99 percent / H2 / 10percent Pd/C / methanol / 3 h / 2275.5 Torr 3: 17 percent / potassium tert-butoxide / CH2Cl2 / 4 h / -78 - 20 °C 4: CF3COOH / CH2Cl2 5: acetone / 35 °C View Scheme

water; sodium acetate T=50°C; pH=4.9; 25 h; Conversion of starting material;

water; sodium acetate T=50°C; pH=4.9; 25 h; Conversion of starting material;

1: Et3N / CH2Cl2 2: H2 / 10percent Pd/C 3: 78 percent / acetic acid / 48 h / Ambient temperature 4: 0.3 percent / pyridine / 1.) 2 deg C, 20 min, 2.) 80 deg C, 80 min 5: 82 percent / trifluoroacetic acid / 0.5 h / Ambient temperature View Scheme

1: Et3N / CH2Cl2 2: H2 / 10percent Pd/C 3: 78 percent / acetic acid / 48 h / Ambient temperature 4: 77 percent / pyridine / 1.) 2 deg C, 20 min, 2.) 80 deg C, 80 min 5: 94 percent / trifluoroacetic acid / 0.5 h / Ambient temperature View Scheme