1.1: hydrogenchloride; sodium nitrite / water / 1 h / Cooling with ice 1.2: 2 h / 0 - 5 °C 2.1: Na2S*9H2O / 1,4-dioxane; water / 80 °C / Inert atmosphere 3.1: acetone / 8 h / 60 °C 4.1: triethylamine / acetone / 0.08 h / 60 °C 4.2: 4 h / 60 °C View Scheme

1.1: hydrogenchloride; sodium nitrite / water / 1 h / Cooling with ice 1.2: 2 h / 0 - 5 °C 2.1: Na2S*9H2O / 1,4-dioxane; water / 80 °C / Inert atmosphere 3.1: acetone / 8 h / 60 °C 4.1: triethylamine / acetone / 0.08 h / 60 °C 4.2: 4 h / 60 °C View Scheme

1.1: acetone / 8 h / 60 °C 2.1: triethylamine / acetone / 0.08 h / 60 °C 2.2: 4 h / 60 °C View Scheme

1.1: Na2S*9H2O / 1,4-dioxane; water / 80 °C / Inert atmosphere 2.1: acetone / 8 h / 60 °C 3.1: triethylamine / acetone / 0.08 h / 60 °C 3.2: 4 h / 60 °C View Scheme