1: 93 percent / iodine, potassium iodide 2: 99 percent / H2 / Adams platinum 3: toluene-p-sulphonic acid / CH2Cl2 / 1.5 h / Ambient temperature 4: H2 / 10percent palladized charcoal / tetrahydrofuran / 760 Torr / Ambient temperature 5: 40 percent / trifluoroacetic acid / 2-3 deg C 70 min, CH2Cl2-CH3OH 18 deg C 2 min 6: 95 percent / H2 / 10percent palladized charcoal / acetic acid / 4 h / Ambient temperature 7: sodium amalgam, aq. acetic acid / 18 h / 37 °C / enzymes from Euglena gracilis 8: 1.) 2M aq. potassium hydroxide; 2.) sodium amalgam / 1.) tetrahydrofuran 20 deg C; 2.) 3-4 min 9: 0.5 h / coproporphyrinogen-III oxidase (from Euglena gracilis) View Scheme

1: 93 percent / iodine, potassium iodide 2: 99 percent / H2 / Adams platinum 3: toluene-p-sulphonic acid / CH2Cl2 / 1.5 h / Ambient temperature 4: H2 / 10percent palladized charcoal / tetrahydrofuran / 760 Torr / Ambient temperature 5: 40 percent / trifluoroacetic acid / 2-3 deg C 70 min, CH2Cl2-CH3OH 18 deg C 2 min 6: 95 percent / H2 / 10percent palladized charcoal / acetic acid / 4 h / Ambient temperature 7: sodium amalgam, aq. acetic acid / 18 h / 37 °C / enzymes from Euglena gracilis 8: 1.) 2M aq. potassium hydroxide; 2.) sodium amalgam / 1.) tetrahydrofuran 20 deg C; 2.) 3-4 min View Scheme