in tetrahydrofuran 1) 1.3 h, T < 38 deg C 2) ca. 0.5 d, to r.t.; Yields of byproduct given;

in tetrahydrofuran 1) 1.3 h, T < 38 deg C 2) ca. 0.5 d, to r.t.; Yields of byproduct given;

1: 81 percent / TiCl4 / CH2Cl2 / 1) -70 deg C, 2) -20 deg C, 2 h 2: 92 percent / ethyl orthoformate / p-TsOH*H2O / 5 h / Heating 3: 98 percent / KOH, NH2NH2*H2O / ethane-1,2-diol / 1.5 h / Heating 4: 1) NaH / 1) DMF, 1 h, 0 deg C, 2) a) 2 h, 0 deg C, b) RT 5: 3.6 percent / conc. HCl / 2 h / Ambient temperature View Scheme

titanium tetrachloride in dichloromethane 1) -70 deg C, 2) -20 deg C, 2 h;

1: 81 percent / TiCl4 / CH2Cl2 / 1) -70 deg C, 2) -20 deg C, 2 h 2: 92 percent / ethyl orthoformate / p-TsOH*H2O / 5 h / Heating 3: 98 percent / KOH, NH2NH2*H2O / ethane-1,2-diol / 1.5 h / Heating View Scheme

1: 81 percent / TiCl4 / CH2Cl2 / 1) -70 deg C, 2) -20 deg C, 2 h 2: 92 percent / ethyl orthoformate / p-TsOH*H2O / 5 h / Heating 3: 98 percent / KOH, NH2NH2*H2O / ethane-1,2-diol / 1.5 h / Heating 4: 1) NaH / 1) DMF, 1 h, 0 deg C, 2) a) 2 h, 0 deg C, b) RT 5: 45 percent / conc. HCl / 2 h / Ambient temperature 6: 50 percent / NaOH / H2O / 1 h / Heating View Scheme

in tetrahydrofuran 1) 1.3 h, T < 38 deg C 2) ca. 0.5 d, to r.t.; Yields of byproduct given;