1: 99 percent / LiAlH4 / diethyl ether / 1 h / 0 °C 2: DMAP, pyridine / tetrahydrofuran / 24 h / Ambient temperature 3: 84 percent / TMSCl, NaI / acetonitrile / -10 °C 4: 86 percent / sodium naphtalenide / 0.08 h / -70 °C 5: 69 percent / PCC, molecular sieves 3A / CH2Cl2 / 0.5 h / Ambient temperature 6: 1.) hexamethyldisilazane, n-BuLi / 1.) THF, n-hexane, -10 deg C, 10 min; 2.) THF, -70 deg C, 1 h; 3.) THF, -5 to 20 deg C, 5 min View Scheme

Multi-step reaction with 10 steps 1: EtN(i-Pr)2 / CH2Cl2 / 24 h / Heating2: OsO4, NaIO4 / diethyl ether; H2O / 7 h3: LiAlH4 / diethyl ether / 0.5 h / below 10 deg C4: pyridine / Ambient temperature5: 75 percent AcOH / 1 h / 30 °C6: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min7: NaOAc / 0.67 h / 130 °C8: 1 percent NaOMe / methanol / 1 h / Ambient temperature9: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C10: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating  

Multi-step reaction with 7 steps 1: pyridine / Ambient temperature2: 75 percent AcOH / 1 h / 30 °C3: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min4: NaOAc / 0.67 h / 130 °C5: 1 percent NaOMe / methanol / 1 h / Ambient temperature6: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C7: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating  

Multi-step reaction with 12 steps 1: 62 percent / 1.) KOH / methanol; H2O / 2 h / Heating2: LiAlH4 / diethyl ether / 1 h / below 10 deg C3: EtN(i-Pr)2 / CH2Cl2 / 24 h / Heating4: OsO4, NaIO4 / diethyl ether; H2O / 7 h5: LiAlH4 / diethyl ether / 0.5 h / below 10 deg C6: pyridine / Ambient temperature7: 75 percent AcOH / 1 h / 30 °C8: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min9: NaOAc / 0.67 h / 130 °C10: 1 percent NaOMe / methanol / 1 h / Ambient temperature11: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C12: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating  

Multi-step reaction with 8 steps 1: LiAlH4 / diethyl ether / 0.5 h / below 10 deg C2: pyridine / Ambient temperature3: 75 percent AcOH / 1 h / 30 °C4: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min5: NaOAc / 0.67 h / 130 °C6: 1 percent NaOMe / methanol / 1 h / Ambient temperature7: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C8: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating  

Multi-step reaction with 5 steps 1: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min2: NaOAc / 0.67 h / 130 °C3: 1 percent NaOMe / methanol / 1 h / Ambient temperature4: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C5: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating  

Multi-step reaction with 6 steps 1: 75 percent AcOH / 1 h / 30 °C2: 1.) LDA / 1.) THF, below -60 deg C, 20 min; 2.) THF, below -60 deg C, 30 min3: NaOAc / 0.67 h / 130 °C4: 1 percent NaOMe / methanol / 1 h / Ambient temperature5: 97 percent / Et3N, DMAP / CH2Cl2 / 7 h / below 0 deg C6: NaN(TMS)2 / 1,2-dimethoxy-ethane / 0.83 h / Heating