1.1: cesium fluoride / toluene / 0.17 h / 0 °C 1.2: 24 h / 0 - 20 °C 2.1: tetrabutyl ammonium fluoride; water / tetrahydrofuran; hexane / 2 h / 50 °C View Scheme

in tetrahydrofuran T=-78 - 20°C; 2 h;

n-butyllithium in tetrahydrofuran -80 deg C to r.t.;

1: tetrahydrofuran / 0.67 h / 20 - 25 °C / |Large scale 2: methanesulfonic acid; hydrogen bromide / n-heptane / 0.5 h / 65 - 75 °C / |Large scale 3: potassium carbonate / N,N-dimethyl-formamide / 0.5 h / |Large scale 4: potassium carbonate / N,N-dimethyl-formamide; water / 35 °C / |Large scale 5: palladium on carbon; acetic acid / tetrahydrofuran / 60 °C / 1725.17 Torr / |Large scale View Scheme