1: 92 percent / i-Pr2NEt / CH2Cl2 / 0.17 h / 0 °C 2: 92 percent / imidazole / CH2Cl2 / 12 h / 20 °C 3: 91 percent / (S)-tol-BINAP; K2CO3 / Pd(OAc)2 / toluene / 16 h / 80 °C 4: 95 percent / TBAF / tetrahydrofuran / 0.17 h / 20 °C 5: 83 percent / LiHMDS; DMAP / tetrahydrofuran / 2 h / -40 - 20 °C View Scheme

1: 92 percent / i-Pr2NEt / CH2Cl2 / 0.17 h / 0 °C 2: 80 percent / Na(O-t-Bu); DPPF / Pd(OAc)2 / toluene / 1 h / 90 °C 3: 72 percent / LiHMDS; DMAP / tetrahydrofuran / 2 h / -40 - 20 °C View Scheme