1: 85 percent / tetrahydrofuran / 0.5 h / Ambient temperature 2: 85 percent / DDQ, CSA / benzene / 5 h / Heating 3: 87 percent / 1N HCl / 12 h / Heating View Scheme

Multi-step reaction with 10 steps 1: 98 percent / Bu4NF / tetrahydrofuran / 1 h / Ambient temperature2: 95 percent / DMSO, Et3N / CH2Cl2 / -60 deg C then warming up to 0 deg C3: DIBAL / toluene / 0.33 h / -78 °C4: 90 percent / (i-Pr)2NEt / tetrahydrofuran / 3 h / Heating5: 94 percent / LiAlH4 / diethyl ether / 1 h / Heating6: 72 percent / CAN / ethanol; H2O / -40 - 0 °C7: Na2S2O4 / CHCl3; H2O / Ambient temperature8: Me3SiBr / CH2Cl2 / 0.17 h / Heating9: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 9 steps 1: 95 percent / DMSO, Et3N / CH2Cl2 / -60 deg C then warming up to 0 deg C2: DIBAL / toluene / 0.33 h / -78 °C3: 90 percent / (i-Pr)2NEt / tetrahydrofuran / 3 h / Heating4: 94 percent / LiAlH4 / diethyl ether / 1 h / Heating5: 72 percent / CAN / ethanol; H2O / -40 - 0 °C6: Na2S2O4 / CHCl3; H2O / Ambient temperature7: Me3SiBr / CH2Cl2 / 0.17 h / Heating8: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 8 steps 1: DIBAL / toluene / 0.33 h / -78 °C2: 90 percent / (i-Pr)2NEt / tetrahydrofuran / 3 h / Heating3: 94 percent / LiAlH4 / diethyl ether / 1 h / Heating4: 72 percent / CAN / ethanol; H2O / -40 - 0 °C5: Na2S2O4 / CHCl3; H2O / Ambient temperature6: Me3SiBr / CH2Cl2 / 0.17 h / Heating7: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 6 steps 1: 94 percent / LiAlH4 / diethyl ether / 1 h / Heating2: 72 percent / CAN / ethanol; H2O / -40 - 0 °C3: Na2S2O4 / CHCl3; H2O / Ambient temperature4: Me3SiBr / CH2Cl2 / 0.17 h / Heating5: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 2 steps 1: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 4 steps 1: Na2S2O4 / CHCl3; H2O / Ambient temperature2: Me3SiBr / CH2Cl2 / 0.17 h / Heating3: AcOK / ethanol / 0.33 h / Ambient temperature  

Multi-step reaction with 3 steps 1: Me3SiBr / CH2Cl2 / 0.17 h / Heating2: AcOK / ethanol / 0.33 h / Ambient temperature  

With  hydrogenchloride  1.) THF, RT, 30 min; 2.) THF, RT, 10 min;  Yield given. Multistep reaction;