1: 93 percent / KOH / H2O / 2 h / 75 °C / Heating 2: 1) NaOMe; 2) HCl gas / 1) toluene, reflux, 15h 2) 1 min (comparable yield with NaH instead of NaOMe) View Scheme

Multistep reaction;

1: 79 percent / CH3I / CH2Cl2 / 72 h / Heating 2: 27 percent / KO2 / dimethylsulfoxide / 0.5 h / Ambient temperature View Scheme