1: 72 percent / aq. formic acid; aq. HCl / 5 °C 2: 88 percent / NaBH4 / methanol / 0.17 h 3: 97 percent / Pb(OAc)4 / acetic acid; acetic anhydride / 2 h / 50 °C 4: 78 percent / phenol, 48percent HBr / 16 h / Heating View Scheme