1: 1) lithium-hexamethyldisilazane / 1) THF, hexane, -60 deg C, 15 min, 2) -20 to 0 deg C 2: 1) lithium-hexamethyldisilazane / 1) THF, hexane, -60 deg C, 15 min, 2) 0 to 10 deg C, 20 min View Scheme

lithium hexamethyldisilazane 1) THF, hexane, -60 deg C, 15 min, 2) 0 to 10 deg C, 20 min; Yield given. Multistep reaction;