1: 20 percent / NaOH / aq. ethanol / 20 h / Ambient temperature 2: 60 percent / hydrogen sulfide, triethylamine / ethanol / 5 °C / ice bath, overnight 3: 99 percent / methanol / 2 h / 66 °C 4: 39 percent / tetrahydrofuran / 3 h / Heating View Scheme

1: 60 percent / hydrogen sulfide, triethylamine / ethanol / 5 °C / ice bath, overnight 2: 99 percent / methanol / 2 h / 66 °C 3: 39 percent / tetrahydrofuran / 3 h / Heating View Scheme

in tetrahydrofuran 3 h; Heating;

1: 99 percent / methanol / 2 h / 66 °C 2: 39 percent / tetrahydrofuran / 3 h / Heating View Scheme

sodium hydroxide in methanol; water 24 h; Heating;