1: tin(IV) chloride / dichloromethane / 20 °C 2: sodium hydroxide / methanol / 12 h / 20 °C 3: triethylsilane; trifluoroacetic acid / 4 h / 20 °C 4: boron trichloride / dichloromethane / 0 °C View Scheme

tin(IV) chloride in dichloromethane T=20°C; Friedel Crafts acylation;