1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 1.) t-BuLi / 1.) toluene, ether, pentane, -100 deg C, 20 min, 2.) toluene, ether, pentane, from -100 deg C to 0 deg C 4: 64 percent / m-chloroperoxybenzoic acid / CH2Cl2 / 2 h / -25 - -5 °C View Scheme

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 1.) t-BuLi / 1.) toluene, ether, pentane, -100 deg C, 20 min, 2.) toluene, ether, pentane, from -100 deg C to 0 deg C View Scheme

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 1.) t-BuLi / 1.) toluene, ether, pentane, -100 deg C, 20 min, 2.) toluene, ether, pentane, - 95 deg C View Scheme

hydrogen bromide in acetic acid T=95 - 100°C; 0.25 h;

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h View Scheme

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 80 percent / 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / tetrahydrofuran / 1 h / 25 °C View Scheme

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 1.) t-BuLi, 2.) CH3OH / 1.) toluene, ether, pentane, -100 deg C, 20 min, 2.) toluene, ether, pentane, - 85 deg C View Scheme

1: 83.5 percent / 48percent HBr, HOAc / 0.25 h / 100 °C 2: 59 percent / H2 / W-2 Raney Ni / tetrahydrofuran; ethanol / 6 h 3: 1.) t-BuLi / 1.) toluene, ether, pentane, -100 deg C, 20 min, 2.) toluene, ether, pentane, from -100 deg C to 0 deg C 4: 49.5percent KHSO5 / tetrahydrofuran; methanol; H2O / 1 h / 30 °C View Scheme