toluene-4-sulfonic acid 1.) THF, -23 deg C, 2 h, 2.) PhH, reflux, 15 min; Yield given. Multistep reaction;

hydrogenchloride 1.) cyclohexane, THF, room temperature, 5 h, 2.) EtOH, reflux, 1 h; Yield given. Multistep reaction;

hydrogenchloride; tert.-butyl lithium 1.) THF, pentane, -78 deg C, 1 h, 2.) cyclohexane, THF, room temperature, 5 h, 3.) EtOH, reflux, 1 h; Yield given. Multistep reaction;