sodium sulfide; sodium hydroxide in ethanol 3 h; Heating;

1: sodium tetrahydroborate; methanol 2: triethylamine / ethyl acetate / 2.5 h / 20 - 50 °C 3: 1,3-dibromo-5,5-dimethyl-hydantoin / acetonitrile / 1 h / 50 °C 4: N,N-dimethyl-formamide / 6 h / 90 °C / |Inert atmosphere 5: hydrogenchloride / isopropyl alcohol View Scheme

1: sodium tetrahydroborate; methanol 2: triethylamine / ethyl acetate / 2.5 h / 20 - 50 °C 3: 1,3-dibromo-5,5-dimethyl-hydantoin / acetonitrile / 1 h / 50 °C 4: N,N-dimethyl-formamide / 6 h / 90 °C / |Inert atmosphere View Scheme

1: sodium tetrahydroborate; methanol 2: triethylamine / ethyl acetate / 2.5 h / 20 - 50 °C 3: 1,3-dibromo-5,5-dimethyl-hydantoin / acetonitrile / 1 h / 50 °C View Scheme

1: 99 percent / 2 h / Ambient temperature 2: 38 percent / ammonium acetate / ethanol / 5 h / Heating View Scheme

methanol; sodium tetrahydroborate