1: acetic acid / tetrahydrofuran / 6 h / 20 °C 2: CH2Cl2 / 6 h / 20 °C 3: CH2Cl2; pentane / 0.5 h / 0 °C 4: hydrogen peroxide; NaOH / 3 h / 20 °C View Scheme

acetic acid in tetrahydrofuran T=20°C; 6 h;