triphenylphosphine in dichloromethane T=0°C; 1 h;

1: 1.) n-butyllithium / 1.) THF-HMPA, -78 deg C, 1 h 2: potassium carbonate / methanol / 3 h / 23 °C 3: triphenylphosphine / CH2Cl2 / 1 h / 0 °C View Scheme

1: potassium carbonate / methanol / 3 h / 23 °C 2: triphenylphosphine / CH2Cl2 / 1 h / 0 °C View Scheme