n-butyllithium; tri-isopropoxy-borane in tetrahydrofuran; hexane T=-80°C; 2 h; Inert atmosphere;

1.1: 87 percent / K2CO3 / acetone / 16 h / 80 °C 2.1: n-BuLi / tetrahydrofuran; hexane / 1 h / -70 °C 2.2: trimethylborate / tetrahydrofuran; hexane / -60 - 20 °C 2.3: 52 percent / aq. HCl / 0.5 h View Scheme

1.1: 98 percent / boron tribromide / CH2Cl2 / -78 - 20 °C 2.1: 87 percent / K2CO3 / acetone / 16 h / 80 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 1 h / -70 °C 3.2: trimethylborate / tetrahydrofuran; hexane / -60 - 20 °C 3.3: 52 percent / aq. HCl / 0.5 h View Scheme

1: potassium iodide; potassium carbonate / N,N-dimethyl-formamide / 48 h / 95 °C 2: N-bromosuccinmide; silica gel / dichloromethane / 8 h / 20 °C 3: tri-isopropoxy-borane; n-butyllithium / tetrahydrofuran; hexane / 2 h / -80 °C / |Inert atmosphere View Scheme

1: potassium iodide; potassium carbonate / N,N-dimethyl-formamide / 48 h / 95 °C 2: N-bromosuccinmide; silica gel / dichloromethane / 8 h / 20 °C 3: tri-isopropoxy-borane; n-butyllithium / tetrahydrofuran; hexane / 2 h / -80 °C / |Inert atmosphere View Scheme

1: N-bromosuccinmide; silica gel / dichloromethane / 8 h / 20 °C 2: tri-isopropoxy-borane; n-butyllithium / tetrahydrofuran; hexane / 2 h / -80 °C / |Inert atmosphere View Scheme