sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride in dichloromethane T=20°C; 0.5 h;

1: 87 percent / tetra-n-butylammonium hydrogen sulfate; aq. NaOH; H2O2 / CH2Cl2 / 1.5 h / 20 °C 2: 84 percent / 4-pyrrolidinopyridine / acetonitrile / 3 h / 20 °C 3: 60 percent / aq. NaOH / dioxane / 2 h / 55 °C View Scheme

sodium hydroxide; dihydrogen peroxide; tetra(n-butyl)ammonium hydrogensulfate in dichloromethane T=20°C; 1.5 h;