1: hydrogen; palladium on activated charcoal / |Inert atmosphere 2: potassium carbonate / 24 h / 20 °C / |Inert atmosphere 3: sodium cyanoborohydride / acetic acid / |Inert atmosphere 4: N-methyl-formamide / 28 h / 50 °C / |Inert atmosphere 5: 2,3-dicyano-5,6-dichloro-p-benzoquinone / tetrahydrofuran / 0.08 h / |Inert atmosphere View Scheme

1: sodium cyanoborohydride / acetic acid / |Inert atmosphere 2: N-methyl-formamide / 28 h / 50 °C / |Inert atmosphere 3: 2,3-dicyano-5,6-dichloro-p-benzoquinone / tetrahydrofuran / 0.08 h / |Inert atmosphere View Scheme

1: potassium carbonate / 24 h / 20 °C / |Inert atmosphere 2: sodium cyanoborohydride / acetic acid / |Inert atmosphere 3: N-methyl-formamide / 28 h / 50 °C / |Inert atmosphere 4: 2,3-dicyano-5,6-dichloro-p-benzoquinone / tetrahydrofuran / 0.08 h / |Inert atmosphere View Scheme

1: hydrogen; palladium on activated charcoal / |Inert atmosphere 2: potassium carbonate / 24 h / 20 °C / |Inert atmosphere 3: sodium cyanoborohydride / acetic acid / |Inert atmosphere 4: N-methyl-formamide / 28 h / 50 °C / |Inert atmosphere 5: 2,3-dicyano-5,6-dichloro-p-benzoquinone / tetrahydrofuran / 0.08 h / |Inert atmosphere View Scheme

1: titanium tetrachloride / tetrahydrofuran; dichloromethane / 5.5 h / 0 - 20 °C / |Inert atmosphere 2: thionyl chloride / dichloromethane / 0.67 h / 0 °C / |Inert atmosphere 3: N-methyl-formamide / 28 h / 50 °C / |Inert atmosphere 4: 2,3-dicyano-5,6-dichloro-p-benzoquinone / tetrahydrofuran / 0.08 h / |Inert atmosphere View Scheme