sodium hydroxide T=20°C; 0.5 h;

Multi-step reaction with 2 steps 1: 66 percent / 2 M NaOH / ethanol; H2O / 1 h / 20 °C2: 1.) 2.2 M n-BuLi / 1.) THF, -70 deg C, 15 min, 2.) THF, -70 to -50 deg C, 60 min  

Multi-step reaction with 3 steps 1: 66 percent / 2 M NaOH / ethanol; H2O / 1 h / 20 °C2: 1.) 2.2 M n-BuLi / 1.) THF, -70 deg C, 15 min, 2.) THF, -70 to -50 deg C, 60 min3: 86 percent / 2.0 M tBuOK / dimethylformamide / 0.08 h / 0 - 5 °C