potassium carbonate in methanol T=20°C; 4 h;

1: 46 percent / K3Fe(CN)6; K2CO3; CH3SO2NH2 / AD-mix β / 2-methyl-propan-2-ol; H2O / 144 h / 4 °C 2: 92 percent / p-toluenesulfonic acid hydrate / methanol / 2 h / 20 °C 3: 96 percent / K2CO3 / methanol / 3 h / 20 °C View Scheme

1: 92 percent / p-toluenesulfonic acid hydrate / methanol / 2 h / 20 °C 2: 96 percent / K2CO3 / methanol / 3 h / 20 °C View Scheme