1: 1.) NBS; 2.) γ-collidine / 1.) hexane, reflux, 1 h; 2.) xylene, reflux, 1 h 2: 64 percent / dimethylsulfoxide; tetrahydrofuran / Ambient temperature 3: 1.) 9-BBN; 2.) NaOH, H2O2 / 1.) THF, r.t., 16 h 4: 86 percent / NaH / xylene / 22 h / Heating View Scheme

1.1: potassium tert-butylate / tetrahydrofuran / 4 h / 25 - 30 °C / |Large scale 2.1: tetrahydrofuran / 4 h / 20 - 45 °C / |Large scale 3.1: sodium hydroxide; dihydrogen peroxide / 1 h / 25 °C / |Large scale 4.1: sodium hydride / tetrahydrofuran; mineral oil / 20 °C / |Large scale 4.2: 1 h / 20 °C / |Reflux; |Large scale 5.1: L-Selectridereg; / tetrahydrofuran / 1 h / |Reflux; |Large scale 6.1: N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile / n-heptane / 0.25 h / 78 °C 7.1: 2,4,6-trimethyl-pyridine / toluene / 2.5 h / 110 °C / |Large scale 8.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 9 h / 66 °C 9.1: tetrahydrofuran / 7 h / 10 °C / |Irradiation 10.1: tetrahydrofuran / 85 h / 25 °C View Scheme

Multi-step reaction with 8 steps 1.1: potassium tert-butylate / tetrahydrofuran / 4 h / 25 - 30 °C / |Large scale2.1: tetrahydrofuran / 4 h / 20 - 45 °C / |Large scale3.1: sodium hydroxide; dihydrogen peroxide / 1 h / 25 °C / |Large scale4.1: sodium hydride / tetrahydrofuran; mineral oil / 20 °C / |Large scale4.2: 1 h / 20 °C / |Reflux; |Large scale5.1: L-Selectridereg; / tetrahydrofuran / 1 h / |Reflux; |Large scale6.1: N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile / n-heptane / 0.25 h / 78 °C7.1: 2,4,6-trimethyl-pyridine / toluene / 2.5 h / 110 °C / |Large scale8.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 9 h / 66 °C  

Multi-step reaction with 6 steps 1: 1.) NBS; 2.) γ-collidine / 1.) hexane, reflux, 1 h; 2.) xylene, reflux, 1 h2: 64 percent / dimethylsulfoxide; tetrahydrofuran / Ambient temperature3: 1.) 9-BBN; 2.) NaOH, H2O2 / 1.) THF, r.t., 16 h4: 1.) NaH; 2.) O2, PdCl2, CuCl / 1.) xylene, reflux, 18 h; 2.) DMF-H2O, r.t. 19 h5: 79 percent / tetrahydrofuran / 1 h / 0 °C  

With  2,4,6-trimethyl-pyridine; N-bromosuccinmide  1.) hexane, reflux, 1 h; 2.) xylene, reflux, 1 h;  Yield given. Multistep reaction;   

Multi-step reaction with 2 steps 1: 89 percent / imidazole / dimethylformamide / 0.5 h / Ambient temperature2: 98 percent / 2,6-lutidine / CH2Cl2 / 0.5 h / Ambient temperature  

Multi-step reaction with 2 steps 1: 1.) NBS; 2.) γ-collidine / 1.) hexane, reflux, 1 h; 2.) xylene, reflux, 1 h2: 64 percent / dimethylsulfoxide; tetrahydrofuran / Ambient temperature  

Multi-step reaction with 4 steps 1: 1.) NBS; 2.) γ-collidine / 1.) hexane, reflux, 1 h; 2.) xylene, reflux, 1 h2: 64 percent / dimethylsulfoxide; tetrahydrofuran / Ambient temperature3: 1.) 9-BBN; 2.) NaOH, H2O2 / 1.) THF, r.t., 16 h4: 86 percent / NaH / xylene / 22 h / Heating