1: N-iodo-succinimide; trifluorormethanesulfonic acid / tetrahydrofuran / 0.33 h / -45 °C / Molecular sieve 2: tetrabutyl ammonium fluoride / tetrahydrofuran / 1 h 3: hydrogenchloride; water; lithium iodide / acetonitrile View Scheme

Yield given. Multistep reaction;

1: 70.5 percent / imidazole / dimethylformamide / 20 h 2: 1.) aq. 50percent NaOH / 1.) DMSO 3: 55.8 percent / tri-n-butyltin hydride, azobisisobutyronitrile / benzene / 60 - 65 °C 4: 84 percent / 1 M tetra-n-butylammonium fluoride / tetrahydrofuran 5: 66 percent / H2 / 10percent Pd/C / methanol / 6 h / 1551.4 Torr 6: 96 percent / ammonia / methanol / 12 h / 50 - 55 °C / in a pressure vessel View Scheme

1: 61 g / pyridine / 20 °C 2: 40 g / DMAP / CH2Cl2 / 3 h 3: 85 percent / TBAF / tetrahydrofuran / 2 h / 20 °C 4: 91 percent / pyridine / 3 h / 20 °C 5: lithium triethylborohydride / tetrahydrofuran / 16 h / cooling View Scheme

1: 61 g / pyridine / 20 °C 2: 40 g / DMAP / CH2Cl2 / 3 h 3: 85 percent / TBAF / tetrahydrofuran / 2 h / 20 °C 4: lithium triethylborohydride / tetrahydrofuran View Scheme

1: pyridine / 5 h / 20 °C 2: 1H-imidazole / dichloromethane; toluene / Inert atmosphere View Scheme

1: 70.5 percent / imidazole / dimethylformamide / 20 h 2: 1.) aq. 50percent NaOH / 1.) DMSO 3: 55.8 percent / tri-n-butyltin hydride, azobisisobutyronitrile / benzene / 60 - 65 °C 4: 84 percent / 1 M tetra-n-butylammonium fluoride / tetrahydrofuran 5: 81 percent / ammonia / methanol / 12 h / 50 - 55 °C / in a pressure vessel View Scheme