1.1: 86 percent / Na2S*2H2O / aq. ethanol 2.1: BH3*Me2S / 1 h / 20 °C 2.2: 61 percent / aq. NaOH; aq. H2O2 / 2 h / 20 °C 3.1: 64 percent / CBr4; Ph3P / tetrahydrofuran / 2 h / 0 °C 4.1: Bu3SnH; AIBN / benzene / 80 °C View Scheme

1.1: 86 percent / Na2S*2H2O / aq. ethanol 2.1: BH3*Me2S / 1 h / 20 °C 2.2: 61 percent / aq. NaOH; aq. H2O2 / 2 h / 20 °C 3.1: NaIO4 / acetone; H2O 3.2: Et3N / 3 h 3.3: 40 mg / tetrahydrofuran; ethanol 4.1: Bu3SnH; AIBN / benzene / 1 h / Heating View Scheme