1: 86 percent / CSA / CH2Cl2; methanol / 1.) 0 deg C, 1 h, 2.) 25 deg C, 0.5 h 2: 82 percent / SO3*pyridine, DMSO, Et3N / CH2Cl2 / 0.5 h / 25 °C 3: LDA / tetrahydrofuran / 1.) -78 to -40 deg C, 0.5 h, 2.) -78 deg C 4: 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 5: K2CO3 / methanol / 0.25 h / 25 °C 6: 79 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 7: 1.) 2,4,6-trichlorobenzoylchloride, Et3N, 2.) 4-DMAP / 1.) THF, 25 deg C, 15 min, 2.) toluene, 25 deg C, 0.5 h 8: 92 percent / CF3COOH / CH2Cl2 / 1 h / 0 °C View Scheme