1: With n-butyllithium in tetrahydrofuran T=-78 - 20°C; 2: With tri-isopropoxy-borane in tetrahydrofuran T=-78 - 20°C;

1: With tert.-butyl lithium in pentane T=-78°C; 0.25 h; 2: With boric acid trimethyl ester in pentane T=-78 - 20°C; 8 h; 3: With ammonium chloride Further stages.;

1.1: SOCl2 / Me3N*HCl / CH2Cl2 / 3 h / Heating 2.1: 1.10 g / AIBN; 2-mercaptopyridine-N-oxide sodium salt hydrate; CBrCl3 / 2 h / Heating 3.1: t-BuLi / pentane / 0.25 h / -78 °C 3.2: B(OMe)3 / pentane / 8 h / -78 - 20 °C 3.3: aq. NH4Cl View Scheme

1.1: 100 percent / BBr3 / CH2Cl2 2.1: 100 percent / imidazole / dimethylformamide 3.1: nBuLi / tetrahydrofuran / -78 - 20 °C 3.2: 36 percent / B(OiPr)3 / tetrahydrofuran / -78 - 20 °C View Scheme

1.1: 100 percent / imidazole / dimethylformamide 2.1: nBuLi / tetrahydrofuran / -78 - 20 °C 2.2: 36 percent / B(OiPr)3 / tetrahydrofuran / -78 - 20 °C View Scheme

1.1: NaNO2; aq. HCl 1.2: 52 percent / aq. KI 2.1: 100 percent / BBr3 / CH2Cl2 3.1: 100 percent / imidazole / dimethylformamide 4.1: nBuLi / tetrahydrofuran / -78 - 20 °C 4.2: 36 percent / B(OiPr)3 / tetrahydrofuran / -78 - 20 °C View Scheme

1.1: 1.10 g / AIBN; 2-mercaptopyridine-N-oxide sodium salt hydrate; CBrCl3 / 2 h / Heating 2.1: t-BuLi / pentane / 0.25 h / -78 °C 2.2: B(OMe)3 / pentane / 8 h / -78 - 20 °C 2.3: aq. NH4Cl View Scheme