hydrogen; palladium over charcoal in methanol 20 h;

1: With trifluoroacetic anhydride T=20°C; 2.5 h; Reflux; 2: With sodium carbonate in dichloromethane; water

1: 2-bromo-5-fluoropyridine With n-butyllithium in hexanes; diethyl ether T=-78°C; 1 h; 2: N,N-dimethyl-formamide in hexanes; diethyl ether 1 h; 3: With sodium tetrahydroborate; water; sodium hydrogencarbonate more than 3 stages;