1: With potassium acetate; acetic anhydride; 18-crown-6 ether in methanol; hexane; chloroform; ethyl acetate T=20 - 75°C; 18 h; Cooling with ice; 2: With hydrogenchloride in methanol; water T=50°C; 2 h;

1: With hydrogenchloride in methanol; water T=100°C; 1 h; 2: With water; potassium hydroxide in methanol Cooling with ice;

1.1: toluene / 1 h / 100 °C 2.1: bromine / acetic acid / 3 h / 20 °C 3.1: acetic anhydride; potassium acetate; iso-amyl nitrate / 18-crown-6 ether / chloroform / 3 h / 65 °C 4.1: hydrogenchloride / water; methanol / 1 h / 100 °C 4.2: Cooling with ice View Scheme

1.1: bromine / acetic acid / 3 h / 20 °C 2.1: acetic anhydride; potassium acetate; iso-amyl nitrate / 18-crown-6 ether / chloroform / 3 h / 65 °C 3.1: hydrogenchloride / water; methanol / 1 h / 100 °C 3.2: Cooling with ice View Scheme

triethylamine; 4-(N,N-dimethlyamino)pyridine in acetonitrile T=0 - 20°C;

1: 5-bromo-6-methyl-1H-indazole With sodium hydride in tetrahydrofuran; mineral oil T=20°C; 0.25 h; 2: methyl iodide in tetrahydrofuran; mineral oil 1.5 h; Cooling with ice;