1: 1.) aq. NaHCO3, 2.) pyridine / 1.) Et2O, RT, 16 h, 2.) from 8 deg C to 10 deg C, 48 h 2: 80 percent / Cs2CO3 / acetonitrile / 8 h / Ambient temperature View Scheme

in tetrahydrofuran T=-70°C; 3 h;

2: 72 percent / NaOH / methanol / 6 h / Heating; pH 9 View Scheme

Yield given. Multistep reaction;

2: 72 percent / NaOH / methanol / 6 h / Heating; pH 9 3: 52 percent / tetrabutylammonium fluoride trihydrate / tetrahydrofuran / 1 h / Ambient temperature View Scheme

1.1: CF3COOH / H2O / 0.5 h / 0 °C 2.1: BuLi / tetrahydrofuran; hexane / 1 h / -78 - -20 °C 2.2: CeCl3 / tetrahydrofuran; hexane / 1 h / -78 °C 2.3: 0.74 g / tetrahydrofuran; hexane / 3 h / -78 °C 3.1: 82 percent / Bu4NF / tetrahydrofuran / 0.5 h / 20 °C View Scheme