1: acetoacetic acid methyl ester With sodium hydride in tetrahydrofuran T=0°C; 0.166667 h; 2: n-butyllithium in tetrahydrofuran; cyclohexane T=0°C; 0.166667 h; 3: 3-fluoro-1-bromomethylbenzene With hydrogenchloride more than 3 stages;