1.1: potassium carbonate / acetone / 6 h / Reflux 2.1: hydrazine / water; diethylene glycol / 120 - 190 °C 2.2: 6 h / 120 - 130 °C 3.1: carbon disulfide / 0.5 h / Inert atmosphere; Cooling with ice 3.2: 19 h / 0 - 20 °C 4.1: ethyl mercaptan sodium salt / N,N-dimethyl-formamide / 16 h / 110 °C View Scheme

1.1: thionyl chloride / 31 h / 20 °C / Reflux 2.1: carbon disulfide / 0.5 h / Inert atmosphere; Cooling with ice 2.2: 19 h / 0 - 20 °C 3.1: ethyl mercaptan sodium salt / N,N-dimethyl-formamide / 16 h / 110 °C View Scheme

1.1: hydrazine / water; diethylene glycol / 120 - 190 °C 1.2: 6 h / 120 - 130 °C 2.1: carbon disulfide / 0.5 h / Inert atmosphere; Cooling with ice 2.2: 19 h / 0 - 20 °C 3.1: ethyl mercaptan sodium salt / N,N-dimethyl-formamide / 16 h / 110 °C View Scheme

1.1: carbon disulfide / 0.5 h / Inert atmosphere; Cooling with ice 1.2: 19 h / 0 - 20 °C 2.1: ethyl mercaptan sodium salt / N,N-dimethyl-formamide / 16 h / 110 °C View Scheme