1: 90 percent / i-Pr2NEt / CH2Cl2 / 2 h / 0 °C 2: 82 percent / DPPP; Et3SiH / Pd(OAc)2 / dimethylformamide / 5 h / 60 °C / 11400 Torr 3: tetrahydrofuran / 50 h / 60 °C 4: 81 percent / DBU / CH2Cl2 / 48 h / 40 °C 5: 76 percent / (R)-BINOL; Ph3PAs=O; molecular sieves 4 Angstroem / La(O-i-Pr)3; TBHP / tetrahydrofuran / 5 h / 20 °C 6: 76 percent / tetrahydrofuran / 0.25 h / -78 °C 7: 74 percent / BF3*THF; NaBH4 / tetrahydrofuran / 1 h / 0 °C 8: 92 percent / aq. HCl / tetrahydrofuran; H2O / 17 h / 35 °C 9: 92 percent / i-Pr2NEt / CH2Cl2 / 0.17 h / 0 °C 10: 92 percent / imidazole / CH2Cl2 / 12 h / 20 °C 11: 91 percent / (S)-tol-BINAP; K2CO3 / Pd(OAc)2 / toluene / 16 h / 80 °C 12: 95 percent / TBAF / tetrahydrofuran / 0.17 h / 20 °C 13: 83 percent / LiHMDS; DMAP / tetrahydrofuran / 2 h / -40 - 20 °C View Scheme

1: 90 percent / i-Pr2NEt / CH2Cl2 / 2 h / 0 °C 2: 82 percent / DPPP; Et3SiH / Pd(OAc)2 / dimethylformamide / 5 h / 60 °C / 11400 Torr 3: tetrahydrofuran / 50 h / 60 °C 4: 81 percent / DBU / CH2Cl2 / 48 h / 40 °C 5: 76 percent / (R)-BINOL; Ph3PAs=O; molecular sieves 4 Angstroem / La(O-i-Pr)3; TBHP / tetrahydrofuran / 5 h / 20 °C 6: 76 percent / tetrahydrofuran / 0.25 h / -78 °C 7: 74 percent / BF3*THF; NaBH4 / tetrahydrofuran / 1 h / 0 °C 8: 92 percent / aq. HCl / tetrahydrofuran; H2O / 17 h / 35 °C 9: 92 percent / i-Pr2NEt / CH2Cl2 / 0.17 h / 0 °C 10: 80 percent / Na(O-t-Bu); DPPF / Pd(OAc)2 / toluene / 1 h / 90 °C 11: 72 percent / LiHMDS; DMAP / tetrahydrofuran / 2 h / -40 - 20 °C View Scheme