diethyl ether; sodium amide Erhitzen des Reaktionsgemisches mit Phenylessigsaeure-aethylester;

1: 1) BuLi / CH2Cl2 / 1) -78 to 0 deg C, 0.5 h, 2) 0 deg C., 1 h 2: SnCl4 / 3 h / -78 °C 3: mCPBA / CH2Cl2 / 1 h / -50 °C 4: NaHCO3 / 1,3,5-trimethyl-benzene / Heating 5: 62 percent / ZnCl2 / trifluoroacetic acid; H2O / 1 h / Ambient temperature View Scheme

1: SnCl4 / 3 h / -78 °C 2: mCPBA / CH2Cl2 / 1 h / -50 °C 3: NaHCO3 / 1,3,5-trimethyl-benzene / Heating 4: 62 percent / ZnCl2 / trifluoroacetic acid; H2O / 1 h / Ambient temperature View Scheme

sodium T=0°C;