hydrazine in 2-ethoxy-ethanol T=160°C; 16 h; Heating / reflux;

1: 3-fluoro-1-bromobenzene With n-butyllithium; diisopropylamine in tetrahydrofuran T=-78°C; 1 h; Inert atmosphere; 2: 2-methylpropanoic anhydride in tetrahydrofuran 0.25 h; Inert atmosphere; 3: With hydrazine hydrate in ethylene glycol T=0 - 100°C;