1.1: 16 percent / potassium carbonate; N-chlorosuccinimide / CH2Cl2 / 140 h / 20 °C 2.1: EtMgCl / toluene; tetrahydrofuran / 0.8 h / -78 °C 2.2: toluene; tetrahydrofuran / Heating 2.3: 56 percent / sodium hydroxide; hydrogen peroxide / various solvents / 3 h / 0 - 20 °C View Scheme