1: With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 2: With tri-isopropoxy-borane in tetrahydrofuran; hexane T=-78 - 20°C; 3: With hydrogenchloride in tetrahydrofuran; hexane Further stages.;

1.1: 96 percent / N-bromosuccinimide / dimethylformamide / 0 °C 2.1: n-BuLi / tetrahydrofuran; hexane / -78 °C 2.2: (i-PrO)3B / tetrahydrofuran; hexane / -78 - 20 °C 2.3: 85 percent / aq. HCl / tetrahydrofuran; hexane View Scheme

1.1: 94 percent / KOH; TBAB / dimethylsulfoxide / 100 °C 2.1: 96 percent / N-bromosuccinimide / dimethylformamide / 0 °C 3.1: n-BuLi / tetrahydrofuran; hexane / -78 °C 3.2: (i-PrO)3B / tetrahydrofuran; hexane / -78 - 20 °C 3.3: 85 percent / aq. HCl / tetrahydrofuran; hexane View Scheme

1.1: 94 percent / KOH; TBAB / dimethylsulfoxide / 100 °C 2.1: 96 percent / N-bromosuccinimide / dimethylformamide / 0 °C 3.1: n-BuLi / tetrahydrofuran; hexane / -78 °C 3.2: (i-PrO)3B / tetrahydrofuran; hexane / -78 - 20 °C 3.3: 85 percent / aq. HCl / tetrahydrofuran; hexane View Scheme