2,2,6,6-tetramethyl-piperidine; n-butyllithium in diethyl ether; hexane T=-75°C; 2 h;

1.1: lithium diisopropylamide / tetrahydrofuran; hexane / 0.75 h / -75 °C 1.2: 66 percent / iodine / tetrahydrofuran; hexane 2.1: 64 percent / potassium fluoride; cuprous iodide; N-methylpyrrolidinone / 20 h / 50 °C 3.1: 68 percent / 2,2,6,6-tetramethylpiperidine; butyllithium / hexane; diethyl ether / 2 h / -75 °C View Scheme

1: 64 percent / potassium fluoride; cuprous iodide; N-methylpyrrolidinone / 20 h / 50 °C 2: 68 percent / 2,2,6,6-tetramethylpiperidine; butyllithium / hexane; diethyl ether / 2 h / -75 °C View Scheme

1: 2-bromo-6-chloro-4-(trifluoromethyl)pyridine With n-butyllithium in hexane; toluene T=-75°C; 0.25 h; 2: carbon dioxide in diethyl ether; hexane; toluene