1: 2.) NaBH4 / 1.) THF, r.t., 1 h, 2.) THF, MeOH, 0 deg C, 0.5 h 2: 50 percent / 70percent HClO4 / tetrahydrofuran; H2O / 3 h / Ambient temperature 3: 62 percent / borane-trimethylamine / acetic acid; tetrahydrofuran / 1 h / 0 °C 4: 1.) 5.25percent NaOCl, 2.) Na2CO3 / 1.) MeOH, 10 min, 2.) MeOH, 1 h View Scheme

Multi-step reaction with 5 steps 1: 81 percent / HCl / Ambient temperature2: 91 percent / conc aq. NH4OH / Ambient temperature3: 75 percent / 5percent Pd/C / xylene / 4 h / Heating4: 77 percent / POCl3 / toluene / Heating5: 94 percent / Br2 / tetrahydrofuran / 1 h  

Multi-step reaction with 2 steps 1: 2.) NaBH4 / 1.) THF, r.t., 1 h, 2.) THF, MeOH, 0 deg C, 0.5 h2: 50 percent / 70percent HClO4 / tetrahydrofuran; H2O / 3 h / Ambient temperature  

Multi-step reaction with 3 steps 1: 2.) NaBH4 / 1.) THF, r.t., 1 h, 2.) THF, MeOH, 0 deg C, 0.5 h2: 50 percent / 70percent HClO4 / tetrahydrofuran; H2O / 3 h / Ambient temperature3: 62 percent / borane-trimethylamine / acetic acid; tetrahydrofuran / 1 h / 0 °C