1: 1.) H2SO4, 2.) o-chloranil / 1.) toluene, reflux, 2h, 2.) reflux, 1h 2: 96 percent / NaBH4 / 1,2-dimethoxy-ethane / 3 h / Heating 3: 95 percent / 150 - 215 °C 4: 87 percent / KOH / acetone / Ambient temperature View Scheme

3,4,5,6-tetrachloro-1,2-benzoquinone; sulfuric acid 1.) toluene, reflux, 2h, 2.) reflux, 1h; Yield given. Multistep reaction;

1: 1.) H2SO4, 2.) o-chloranil / 1.) toluene, reflux, 2h, 2.) reflux, 1h 2: 96 percent / NaBH4 / 1,2-dimethoxy-ethane / 3 h / Heating View Scheme