silica gel; copper(II) nitrate in tetrachloromethane 0.25 h; Ambient temperature;

zeolite HSZ-360 in dichloromethane 15 h; Ambient temperature;

toluene-4-sulfonic acid in benzene 2 h; Heating;

1: 1.) sec-BuLi, TMEDA / 1.) cyclohexane, THF, -78 deg C, 0.5 h at -55 deg C, 2.) -50 deg C, warmed to 20 deg C over 3 h 2: 78 percent / p-toluenesulfonic acid monohydrate / benzene / 2 h / Heating View Scheme

Yield given. Multistep reaction;