1: imidazole / CH2Cl2 / 1 h 2: 0.331 g / triphenylphosphine / bis(triphenylphosphine)palladium(II) chloride; copper(I) iodide / tetrahydrofuran; triethylamine / 24 h / 50 °C 3: 98 percent / pyridinium chlorochromate; celite / CH2Cl2 / 12 h / 20 °C 4: potassium fluoride / dimethylformamide / 48 h / 60 °C View Scheme

Celite; pyridinium chlorochromate in dichloromethane 2 h; Yield given;

potassium hydrogensulfate; hydroquinone Erhitzen unter vermindertem Druck;