1.1: xylene / 16 h / 130 °C 2.1: 110 g / aq. HCl / xylene; tetrahydrofuran / 2 h / 50 °C 3.1: potassium tert-butoxide / tetrahydrofuran / 1 h / -5 °C 3.2: 97 percent / tetrahydrofuran / 20 h / 22 °C 4.1: 94 percent / L-selectride / tetrahydrofuran / 1.5 h / -60 °C 5.1: 96 percent / diisobutylaluminium hydride / toluene / 1 h / -40 °C 6.1: potassium tert-butoxide / tetrahydrofuran / cooling 6.2: tetrahydrofuran; toluene / -20 - 20 °C 7.1: 5.6 kg / aq. HCl / tetrahydrofuran; toluene; dimethylformamide / 2 h / 45 °C 8.1: 74 percent / sulfamic acid; sodium chlorite / CH2Cl2; H2O / 0.5 h View Scheme

bis-dimethylamino-methane in DMF (N,N-dimethyl-formamide) T=60°C; 5 h;

acetic anhydride in N,N-dimethyl-formamide T=60°C; 24.5 h;

1: 96 percent / sodium tungstate dihydrate; sulfuric acid; hydrogen peroxide / aliquat 336 / H2O; toluene / 45 °C 2: 92 percent / acetic anhydride / dimethylformamide / 24.5 h / 60 °C View Scheme

1: 100 percent / sodium hydroxide / ethanol / cooling 2: 96 percent / sodium tungstate dihydrate; sulfuric acid; hydrogen peroxide / aliquat 336 / H2O; toluene / 45 °C 3: 92 percent / acetic anhydride / dimethylformamide / 24.5 h / 60 °C View Scheme

1: 100 percent / sodium hydroxide / ethanol / cooling 2: 96 percent / sodium tungstate dihydrate; sulfuric acid; hydrogen peroxide / aliquat 336 / H2O; toluene / 45 °C 3: 92 percent / acetic anhydride / dimethylformamide / 24.5 h / 60 °C View Scheme

acetic anhydride in N,N-dimethyl-formamide T=60°C; 2.5 h;

1.1: xylene / 16 h / 130 °C 2.1: 110 g / aq. HCl / xylene; tetrahydrofuran / 2 h / 50 °C 3.1: potassium tert-butoxide / tetrahydrofuran / 1 h / -5 °C 3.2: 97 percent / tetrahydrofuran / 20 h / 22 °C View Scheme

1.1: xylene / 16 h / 130 °C 2.1: 110 g / aq. HCl / xylene; tetrahydrofuran / 2 h / 50 °C 3.1: potassium tert-butoxide / tetrahydrofuran / 1 h / -5 °C 3.2: 97 percent / tetrahydrofuran / 20 h / 22 °C 4.1: 94 percent / L-selectride / tetrahydrofuran / 1.5 h / -60 °C 5.1: 96 percent / diisobutylaluminium hydride / toluene / 1 h / -40 °C View Scheme

1: in xylenes T=130°C; 2: With hydrogenchloride in tetrahydrofuran; water; xylenes T=50°C;