n-butyllithium; diisopropylamine in tetrahydrofuran; hexane T=-75°C; 2 h;

1: 88 percent / phosphorus oxybromide / 2 h / 150 °C 2: 88 percent / butyllithium; diisopropylamine / tetrahydrofuran; hexane / 2 h / -75 °C View Scheme

1: 51 percent / polyphosphoric acid / 2 h / 150 °C 2: 88 percent / phosphorus oxybromide / 2 h / 150 °C 3: 88 percent / butyllithium; diisopropylamine / tetrahydrofuran; hexane / 2 h / -75 °C View Scheme

potassium carbonate in acetone T=25°C; 6 h;