1: 4-chloro-2-fluoro-1-methoxybenzene With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.5 h; 2: carbon dioxide in tetrahydrofuran; hexane T=-78 - 20°C; 4 h; 3: With hydrogenchloride; sodium hydroxide more than 3 stages;

boron tribromide in dichloromethane T=0 - 20°C; Product distribution / selectivity;