2: NaNO2, KBr, 2.5 N aq. HBr / 2 h / -9 - -7 °C 3: 82 percent / H2SO4 / 2-methyl-propan-2-ol; dioxane / 18 h 4: 1.) Zn(Ag), Cu(I)Br, Et2AlCl / 1.) THF, hexane, 1 h, 2.) THF, RT, 1.5 h 5: 96 percent / CH2Cl2 / 18 h / Ambient temperature 6: oxalyl chloride, DMF / CH2Cl2 / 1.) 0 deg C, 10 min, 2.) RT, 4 h 7: NaBH4 / dimethylformamide 8: ammonium formate / Pd/C (10percent) / methanol / 1.) RT, 10 min, 2.) 60-70 deg C, 21 h 9: 2 N aq. HCl / methanol View Scheme