1: aq. 10percent H2SO4 / methanol; H2O / 1 h / Ambient temperature 2: 90 percent / hydrogen peroxide, potassium hydroxide / methanol; H2O / 1 h / 15 °C 3: 7.8 g / tosyl hydrazine / acetic acid; CH2Cl2 / 8 h / Ambient temperature 4: 2.2 g / tetrahydrofuran / 3 h / Ambient temperature 5: 1.62 g / pyridine-chromic anhydride complex / CH2Cl2 / 0.25 h / Ambient temperature 6: 1.6 g / hydrogen, pyridine / 10percent Pd-BaSO4 / ethyl acetate View Scheme

sulfuric acid in methanol; water 1 h; Ambient temperature; Yield given;

1: aq. 10percent H2SO4 / methanol; H2O / 1 h / Ambient temperature 2: 90 percent / hydrogen peroxide, potassium hydroxide / methanol; H2O / 1 h / 15 °C 3: 7.8 g / tosyl hydrazine / acetic acid; CH2Cl2 / 8 h / Ambient temperature 4: 2.2 g / tetrahydrofuran / 3 h / Ambient temperature View Scheme

1: aq. 10percent H2SO4 / methanol; H2O / 1 h / Ambient temperature 2: 90 percent / hydrogen peroxide, potassium hydroxide / methanol; H2O / 1 h / 15 °C 3: 7.8 g / tosyl hydrazine / acetic acid; CH2Cl2 / 8 h / Ambient temperature 4: 2.2 g / tetrahydrofuran / 3 h / Ambient temperature 5: 1.62 g / pyridine-chromic anhydride complex / CH2Cl2 / 0.25 h / Ambient temperature View Scheme