palladium 10 on activated carbon; hydrogen in tetrahydrofuran; methanol T=20°C; 3 h;

1.1: potassium carbonate; potassium iodide / N,N-dimethyl-formamide / 8 h / 50 °C 2.1: trifluoroacetic acid / toluene / 2 h / 20 °C 3.1: potassium hydroxide / ethanol; water / 36 h / 20 °C 3.2: pH Ca. 5 / Cooling with ice 4.1: iodine; dimethyl sulfoxide / 12 h / 110 °C 5.1: palladium 10 on activated carbon; hydrogen / tetrahydrofuran; methanol / 3 h / 20 °C View Scheme

1.1: trifluoroacetic acid / toluene / 2 h / 20 °C 2.1: potassium hydroxide / ethanol; water / 36 h / 20 °C 2.2: pH Ca. 5 / Cooling with ice 3.1: iodine; dimethyl sulfoxide / 12 h / 110 °C 4.1: palladium 10 on activated carbon; hydrogen / tetrahydrofuran; methanol / 3 h / 20 °C View Scheme

1.1: potassium hydroxide / ethanol; water / 36 h / 20 °C 1.2: pH Ca. 5 / Cooling with ice 2.1: iodine; dimethyl sulfoxide / 12 h / 110 °C 3.1: palladium 10 on activated carbon; hydrogen / tetrahydrofuran; methanol / 3 h / 20 °C View Scheme