in methanol T=66°C; 2 h;

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 View Scheme

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

in tetrahydrofuran 3 h; Heating;

1: 39 percent / tetrahydrofuran / 3 h / Heating 2: 38 percent / sodium hydroxide / methanol; H2O / 24 h / Heating View Scheme