1: 84 percent / imidazole; DMAP / dimethylformamide 2: 100 percent / aq. acetic acid / dimethylformamide 3: 92 percent / DMAP / pyridine 4: 86 percent / sodium borohydride / methanol 5: 95 percent / sodium azide / dimethylformamide 6: 90 percent / DMAP / pyridine 7: 98 percent / hydrogen / Pd/C / methanol 8: 71 percent / potassium tert-butoxide / dimethylformamide; benzene 9: 57 percent / tetrabutylammonium fluoride / tetrahydrofuran 10: 93 percent / carbon tetrabromide; triphenylphosphine / CH2Cl2 11: 80 percent / potassium tert-butoxide / dimethylsulfoxide 12: 95 percent / ozone / methanol View Scheme