1: NaH / dimethylformamide / 0.25 h / 60 °C 2: 1.) n-butyllithium, 2.) acetaldehyde / 1.) THF, hexane, -78 deg C, 5 min, 2.) THF, hexane, -78 deg C to 0 deg C, 20 min View Scheme

n-butyllithium; acetaldehyde 1.) THF, hexane, -78 deg C, 5 min, 2.) THF, hexane, -78 deg C to 0 deg C, 20 min; Yield given. Multistep reaction. Yields of byproduct given;

n-butyllithium 1.) THF, hexane, -78 deg C, 5 min, 2.) THF, hexane, -78 deg C to 0 deg C, 20 min; Yield given. Multistep reaction. Yields of byproduct given;