1: With potassium hydroxide; water 48 h; Heating / reflux; 2: With hydrogenchloride in water pH=1;

hydrogen bromide

1: aqueous HNO3 2: aqueous NaOH View Scheme

potassium carbonate in N,N-dimethyl-formamide T=20°C;

hydrogenchloride 10 h; Heating;

potassium hydrogencarbonate in N,N-dimethyl-formamide T=40°C; 2 h; Inert atmosphere;

potassium carbonate in N,N-dimethyl-formamide T=65°C; 36 h;

1: 81 percent / K2CO3 / dimethylformamide / 36 h / 65 °C 2: 80 percent / KOH / tetrahydrofuran; H2O; methanol / 12 h 3: 1.) oxalyl chloride, DMF, 2.) triethylamine / 1.) CH2Cl2, reflux, 40 min, 2.) THF, 0 deg C, 30 min 4: 1.) Na2S2SO4, 2.) aq. HCl / 1.) THF, H2O, room temp., 1.5 d, 2.) THF, H2O, room temp., 2 d 5: 89 percent / H2 / Pd/C / methanol / 5 h / 60 °C / 2068.6 Torr 6: 79.4 percent / 24 h / Heating 7: 70 percent / oxalyl chloride, DMSO / CH2Cl2 / 1 h / -78 °C 8: 90 percent / pyridine / CH2Cl2 / 3 h / Ambient temperature 9: 50 percent / DABCO / (CH3CN)2PdCl2 / methanol / 45 °C 10: 99 percent / NaBH4 / methanol / 4.5 h 11: 0.1 M aq. HCl / 2 h / Ambient temperature View Scheme

1: 68 percent / HCl / 10 h / Heating 2: H2 / 5percent Pd/C / methanol / 2 h / 760 Torr View Scheme

sodium hydroxide; potassium borohydride; palladium on activated charcoal in methanol; water 2 h;