methanesulfonic acid T=80°C; 0.416667 h; Cooling with ice;

1: N'-(2-bromo-4-isopropylphenyl)-N,N-dimethylurea With methyllithium in tetrahydrofuran; diethyl ether T=0°C; 2: With tert.-butyl lithium in tetrahydrofuran; diethyl ether; n-heptane T=0°C; 1 h; 3: carbon monoxide in tetrahydrofuran; diethyl ether; n-heptane T=0°C; 0.5 h;

H-β zeolite in 1,2-dichloro-ethane T=80°C; 24 h; Inert atmosphere;

1: hydroxylamine hydrochloride; sodium sulfate; aq. HCl / 55 °C 2: 71 percent / conc. sulfuric acid / 55 - 80 °C View Scheme

1.1: Et3N / tetrahydrofuran / 2 h / 0 °C 1.2: 70 percent / tetrahydrofuran / 1 h / 0 °C 2.1: MeLi / tetrahydrofuran; diethyl ether / 0 °C 2.2: t-BuLi / tetrahydrofuran; diethyl ether; heptane / 1 h / 0 °C 2.3: 71 percent / tetrahydrofuran; diethyl ether; heptane / 0.5 h / 0 °C View Scheme