potassium permanganate; tetrabutylammomium bromide in water; benzene 1) 30 min, 5-10 deg C; 2) 30 min, 50 deg C;

1: 86 percent / KMnO4, tetrabutylammoniumbromide / benzene; H2O / 1) 30 min, 5-10 deg C; 2) 30 min, 50 deg C 2: 19 percent / H2S, 25 percent NH3 / 2 h / Heating View Scheme