water; sodium hydroxide in 2-methyl tetrahydrofuran T=25 - 28°C; 1 h;

1.1: sodium hydrogencarbonate / 2-methyl tetrahydrofuran; water / 0.5 h / Cooling 1.2: 3 h / 10 °C / Cooling 2.1: water; sodium hydroxide / 2-methyl tetrahydrofuran / 1 h / 25 - 28 °C View Scheme

the presence of alkali;