1: 98 percent / hydrogen / Pd/C / methanol 2: 71 percent / potassium tert-butoxide / dimethylformamide; benzene 3: 57 percent / tetrabutylammonium fluoride / tetrahydrofuran 4: 93 percent / carbon tetrabromide; triphenylphosphine / CH2Cl2 5: 80 percent / potassium tert-butoxide / dimethylsulfoxide 6: 95 percent / ozone / methanol View Scheme