1: pyridine-2,3-dicarboxylic acid ester With sulfur(IV) fluoride; hydrogen fluoride T=60°C; 24 h; 2: methanol T=80°C; 3 h;

1: 3-trifluoromethylpyridine; carbon dioxide With n-butyllithium; diisopropylamine in tetrahydrofuran; hexane T=-75°C; 2 h; 2: diazomethane in diethyl ether