1: 99 percent / Hg(OAc)2; acetic acid / CHCl3 / 4 h / 20 °C 2: 95 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / chlorobenzene / Heating View Scheme

1: 99 percent / Hg(OAc)2; acetic acid / CHCl3 / 4 h / 20 °C 2: 95 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / chlorobenzene / Heating 3: 84 percent / triethyl phosphite / 5 h / 120 °C 4: 100 percent / sodium methoxide / tetrahydrofuran; methanol / 0.5 h / Heating View Scheme

2,3-dicyano-5,6-dichloro-p-benzoquinone in chlorobenzene Oxidation; 16 h; Heating;