1: 94 percent / aq. HOAc / 1 h / 70 °C 2: 1.) BF3*OEt2, 4A MS, 2.) 2,6-lutidine / 1.) CH2Cl2, -60 deg C, 30 min, 2.) CH2Cl2, -20 deg C, 1 h 3: 50 percent / H2, Et3N / Pd/C / ethyl acetate; ethanol / 72 h / 50 °C / 38000 Torr 4: 65 percent / DBU / CH2Cl2 / 6 h / Ambient temperature 5: 69 percent / 4A MS, TMSOTf / CH2Cl2 / 0.33 h / -20 °C 6: 79 percent / Pd(MeCN)2Cl2 / acetone; H2O / Ambient temperature View Scheme