(PhCH2PPh3)(+)Br3(-); calcium carbonate in methanol; dichloromethane T=20°C; 1 h;

potassium carbonate in acetone 24 h; Heating;

1.1: 76 percent / K2CO3 / acetone / 24 h / Heating 2.1: n-BuLi / tetrahydrofuran; hexane; diethyl ether / 0.08 h / -98 °C 2.2: B(OMe)3 / tetrahydrofuran; hexane; diethyl ether / 12 h / -98 - 20 °C 2.3: 65 percent / aq. HCl / tetrahydrofuran; hexane; diethyl ether / 20 °C View Scheme