1: 81 percent / glacial acetic acid / H2O / 1.5 h / 80 - 90 °C 2: 86 percent / glacial acetic acid, H2O2 / tetrahydrofuran / 1) 0 deg C, 0.25 h, 2) warm to RT, 1 h View Scheme

dihydrogen peroxide; acetic acid in tetrahydrofuran 1) 0 deg C, 0.25 h, 2) warm to RT over 1 h;

1: 24 percent / pyridine, H2O2 / CH2Cl2 / 1) -50 deg C, 5 min, 2) warm to 0 deg C, 0.5 h 2: 1) Na / 1a) THF, reflux, 4 h, 1b) HMPA, heating, 3 h, 2) heating, 8 h View Scheme

pyridine; dihydrogen peroxide in dichloromethane 1) -50 deg C, 5 min, 2) warm to 0 deg C, 0.5 h;