lithium aluminium tetrahydride in tetrahydrofuran T=-78°C; 1 h;

manganese(IV) oxide in chloroform 0.75 h; Reflux;

1: 4-bromo-pyridine-hydrochloride With methyl-magnesium chloride in tetrahydrofuran T=-78°C; 0.25 h; 2: phenyl chloroformate in tetrahydrofuran T=-78 - 20°C; 3: With water; ammonium chloride in tetrahydrofuran T=0°C;

acetyl-bromide T=60 - 70°C; 15 h; Inert atmosphereSchlenk technique;

selenium(IV) oxide in 1,4-dioxane 12 h; RefluxInert atmosphere;

1: 67 percent / 1 h / 100 °C 2: 94 percent / aq. HCl / 16 h / 80 °C 3: 86 percent / DMSO, (COCl)2, Et3N / CH2Cl2 View Scheme

1: 95 percent / H2SO4, fuming HNO3 / 2 h / 100 - 105 °C 2: 85 percent / PCl3 / CHCl3 / 3 h / Ambient temperature 3: 61 percent / AcBr / 6 h / Heating 4: KMnO4 / H2O / Heating 5: 1) NEt3, ethyl chloroformate, 2) LiAlH4 / 1) benzene, rt, 1 h, 2) THF, -78 deg C, 30 min 6: 69 percent / DMSO, N,N'-dicyclohexylcarbodiimide, H3PO4 / 1.5 h / Ambient temperature View Scheme

1: 85 percent / PCl3 / CHCl3 / 3 h / Ambient temperature 2: 61 percent / AcBr / 6 h / Heating 3: KMnO4 / H2O / Heating 4: 1) NEt3, ethyl chloroformate, 2) LiAlH4 / 1) benzene, rt, 1 h, 2) THF, -78 deg C, 30 min 5: 69 percent / DMSO, N,N'-dicyclohexylcarbodiimide, H3PO4 / 1.5 h / Ambient temperature View Scheme

1: 94 percent / aq. HCl / 16 h / 80 °C 2: 86 percent / DMSO, (COCl)2, Et3N / CH2Cl2 View Scheme

1: 61 percent / AcBr / 6 h / Heating 2: KMnO4 / H2O / Heating 3: 1) NEt3, ethyl chloroformate, 2) LiAlH4 / 1) benzene, rt, 1 h, 2) THF, -78 deg C, 30 min 4: 69 percent / DMSO, N,N'-dicyclohexylcarbodiimide, H3PO4 / 1.5 h / Ambient temperature View Scheme