1: With methanesulfonic acid in ethanol; di-isopropyl ether T=20°C; 0.833333 h; 2: With triethylamine in hexane; water; ethyl acetate T=20°C; 1 h;

1.1: methanesulfonic acid / di-isopropyl ether; ethanol / 0.83 h / 20 °C 1.2: 1 h / 20 °C 2.1: sodium hydroxide; water; dipotassium hydrogenphosphate; sodium tetrahydroborate / ethanol; methanol / 1.5 h / 12 - 20 °C 2.2: 8 h / 20 °C 3.1: triethylamine / isopropyl alcohol / 4 h / 20 °C View Scheme