1: With magnesium; ethylene dibromide in tetrahydrofuran T=20°C; Inert atmosphere; 2: With boric acid trimethyl ester in tetrahydrofuran T=-78 - 20°C; Inert atmosphere; 3: With hydrogenchloride; water in tetrahydrofuran

1.1: 74 percent / 20 percent aq. Na2CO3; Pd(PPh3)4 / toluene; 1,2-dimethoxy-ethane / 6 h / Heating 2.1: n-BuLi / tetrahydrofuran; hexane / 0.33 h / -78 °C 2.2: tetrahydrofuran; hexane / 1 h / -78 - 20 °C 3.1: 10 percent aq. HCl / hexane; tetrahydrofuran / 1 h / 20 °C View Scheme

1.1: 74 percent / 20 percent aq. Na2CO3; Pd(PPh3)4 / toluene; 1,2-dimethoxy-ethane / 6 h / Heating 2.1: n-BuLi / tetrahydrofuran; hexane / 0.33 h / -78 °C 2.2: tetrahydrofuran; hexane / 1 h / -78 - 20 °C 3.1: 10 percent aq. HCl / hexane; tetrahydrofuran / 1 h / 20 °C View Scheme