potassium tert-butylate in tetrahydrofuran T=-5 - 45°C;

potassium tert-butylate in tetrahydrofuran T=-5 - 45°C;

N-ethyl-N,N-diisopropylamine in N,N-dimethyl-formamide T=20°C;

1.1: 83 percent / NaBH(OAc)3 / acetic acid / 19 h / 20 - 50 °C 2.1: 98 percent / H2 / Pd/C / methanol / 20 h / 2585.74 Torr 3.1: 97 percent / K2CO3 / dimethylformamide / 5 h / 20 - 50 °C 4.1: HCl gas / acetonitrile / 0.5 h / 0 - 20 °C 4.2: acetonitrile / 2 h / -10 - 0 °C 4.3: 86.5 percent / acetonitrile / 1 h / -10 - 0 °C 5.1: 75 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme

1.1: 84 percent / TMSCl / 22 h / Heating 2.1: 100 percent / H2 / Pd/C / methanol / 20 °C / 1034.3 - 2585.74 Torr 3.1: 83 percent / NaBH(OAc)3 / acetic acid / 19 h / 20 - 50 °C 4.1: 98 percent / H2 / Pd/C / methanol / 20 h / 2585.74 Torr 5.1: 97 percent / K2CO3 / dimethylformamide / 5 h / 20 - 50 °C 6.1: HCl gas / acetonitrile / 0.5 h / 0 - 20 °C 6.2: acetonitrile / 2 h / -10 - 0 °C 6.3: 86.5 percent / acetonitrile / 1 h / -10 - 0 °C 7.1: 75 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme

1.1: 100 percent / H2 / Pd/C / methanol / 20 °C / 1034.3 - 2585.74 Torr 2.1: 83 percent / NaBH(OAc)3 / acetic acid / 19 h / 20 - 50 °C 3.1: 98 percent / H2 / Pd/C / methanol / 20 h / 2585.74 Torr 4.1: 97 percent / K2CO3 / dimethylformamide / 5 h / 20 - 50 °C 5.1: HCl gas / acetonitrile / 0.5 h / 0 - 20 °C 5.2: acetonitrile / 2 h / -10 - 0 °C 5.3: 86.5 percent / acetonitrile / 1 h / -10 - 0 °C 6.1: 75 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme

1.1: 98 percent / H2 / Pd/C / methanol / 20 h / 2585.74 Torr 2.1: 97 percent / K2CO3 / dimethylformamide / 5 h / 20 - 50 °C 3.1: HCl gas / acetonitrile / 0.5 h / 0 - 20 °C 3.2: acetonitrile / 2 h / -10 - 0 °C 3.3: 86.5 percent / acetonitrile / 1 h / -10 - 0 °C 4.1: 75 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme

1: With triethylamine in dichloromethane T=20°C; 4 h; 2: With toluene-4-sulfonic acid in dichloromethane 3.5 h;

1: 58 percent / HCl; BH3*pyridine / methanol / 1 h / 20 °C 2: 96 percent / NaBH(OAc)3 / acetic acid / 1 h / 20 °C 3: 85 percent / DDQ / tetrahydrofuran / 21 h / 20 °C 4: 41 percent / HCl / ethyl acetate; dioxane / 20 °C 5: 82 percent / K2CO3 / dimethylformamide / 20 - 50 °C 6: 53 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme

1: 96 percent / NaBH(OAc)3 / acetic acid / 1 h / 20 °C 2: 85 percent / DDQ / tetrahydrofuran / 21 h / 20 °C 3: 41 percent / HCl / ethyl acetate; dioxane / 20 °C 4: 82 percent / K2CO3 / dimethylformamide / 20 - 50 °C 5: 53 percent / t-BuOK / tetrahydrofuran / -5 - 45 °C View Scheme