2-Chloro-2-methylpropane; lithium 1.) THF, 0 deg C, ultrasound irradiation, 10 min, 2.) THF, 2 h; Yield given. Multistep reaction;

2-Chloro-2-methylpropane; lithium 1.) THF, 5 h 2.) 0.5 h; Yield given. Multistep reaction;