1: 1.) acetic anhydride, 2.) K2CO3 / 1.) 90 deg C, 2 h, 2.) MeOH, 1 h, RT 2: 73 percent / ammonia, lithium / diethyl ether; ethanol / 3 h / -33 °C 3: 98 percent / imidazole / dimethylformamide / 1 h / Ambient temperature 4: methanesulfonyl chloride, N,N-dimethylaminopyridine, 2.) lithium bromide, lithium carbonate / 1.) CH2Cl2, RT, 1 h, 2.) DMF, 150 deg C, 2 h 5: 80 percent / p-toluenesulfonic acid / nitromethane / 18 h / Ambient temperature View Scheme