sulfuric acid in water T=20 - 85°C; 4 h;

1.1: TMEDA; n-BuLi / tetrahydrofuran; hexane / 2 h / 0 °C 1.2: 48 percent / ethanol; hexane / 2.5 h / -78 - 20 °C 2.1: 99 percent / HCl / 1,2-dimethoxy-ethane / 5 h / Heating 3.1: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 4.1: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 5.1: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 2: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 3: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 2: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1: 99 percent / HCl / 1,2-dimethoxy-ethane / 5 h / Heating 2: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 3: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 4: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1.1: 98 percent / K2CO3 / acetone / 3.5 h / Heating 2.1: 58 percent / NH3(liquid); Na; iron nitrate nonahydrate / acetone / 2 h / Heating 3.1: 94 percent / Et3N / CH2Cl2 / 0.5 h / 20 °C 4.1: TMEDA; n-BuLi / tetrahydrofuran; hexane / 2 h / 0 °C 4.2: 48 percent / ethanol; hexane / 2.5 h / -78 - 20 °C 5.1: 99 percent / HCl / 1,2-dimethoxy-ethane / 5 h / Heating 6.1: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 7.1: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 8.1: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1.1: 94 percent / Et3N / CH2Cl2 / 0.5 h / 20 °C 2.1: TMEDA; n-BuLi / tetrahydrofuran; hexane / 2 h / 0 °C 2.2: 48 percent / ethanol; hexane / 2.5 h / -78 - 20 °C 3.1: 99 percent / HCl / 1,2-dimethoxy-ethane / 5 h / Heating 4.1: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 5.1: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 6.1: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme

1.1: 58 percent / NH3(liquid); Na; iron nitrate nonahydrate / acetone / 2 h / Heating 2.1: 94 percent / Et3N / CH2Cl2 / 0.5 h / 20 °C 3.1: TMEDA; n-BuLi / tetrahydrofuran; hexane / 2 h / 0 °C 3.2: 48 percent / ethanol; hexane / 2.5 h / -78 - 20 °C 4.1: 99 percent / HCl / 1,2-dimethoxy-ethane / 5 h / Heating 5.1: 90 percent / p-TsOH*H2O / methanol / 6 h / Heating 6.1: 91 percent / NaH; O-(diphenylphosphinyl)hydroxylamine / tetrahydrofuran / 0.75 h / 0 - 20 °C 7.1: H2SO4 / H2O / 4 h / 20 - 85 °C View Scheme