1: thionyl chloride / 4-(N,N-dimethlyamino)pyridine / tert-butyl methyl ether / 1.5 h / 15 - 30 °C 2: dimethyl sulfoxide / 1 h / 30 - 40 °C 3: tetra-n-octylammonium bromide; potassium hydroxide / water / 1 h / 70 °C 4: sodium hydroxide; water / ethanol / 80 °C View Scheme

1.1: 4-(N,N-dimethlyamino)pyridine; thionyl chloride / tert-butyl methyl ether / 1 h / 15 - 30 °C 2.1: dimethyl sulfoxide / 1 h / 30 - 40 °C 2.2: 0.5 h 3.1: potassium hydroxide; tetra-n-octylammonium bromide / water / 1 h / 70 °C 4.1: sodium hydroxide; water / ethanol / 80 °C 5.1: thionyl chloride / toluene / 0.5 h / 60 °C 6.1: triethylamine; 4-(N,N-dimethlyamino)pyridine / toluene / 2 h 7.1: hydrogenchloride; water / acetonitrile / 40 - 45 °C View Scheme

1: With sodium bis(2-methoxyethoxy)aluminium dihydride in toluene T=15 - 40°C; 2: With sodium hydroxide in water; toluene T=40 - 50°C;

sodium tetrahydroborate in tetrahydrofuran T=0°C; 1 h; Product distribution / selectivity;

10 palladium on activated charcoal; hydrogen in ethanol T=50°C; P=760.051 Torr;

in toluene

methanol; sodium tetrahydroborate

palladium 10 on activated carbon; hydrogen in methanol T=50°C; P=15001.5 Torr;

10 platinum on carbon; hydrogen in methanol T=50°C; P=760.051 Torr;

1: triethylamine / tetrakis (triphenylphosphine) palladium (0) / methanol; acetonitrile 2: sodium hydroxide; lithium aluminum hydride / tetrahydrofuran; water View Scheme