1: 95 percent / 4-DMAP, Et3N / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 95 percent / H2 / Pd(OH)2-C / tetrahydrofuran / 0.25 h / 25 °C / 2585.7 Torr 3: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 45 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min View Scheme

1: 98 percent / NaBH4 / methanol / 0.25 h / 0 °C 2: 95 percent / Et3N / CH2Cl2 / 12 h 3: 95 percent / H2 / Pd(OH)2 / tetrahydrofuran / 0.25 h / 25 °C / 2068.6 Torr 4: 91 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 5: 92 percent / 2 h / 100 °C 6: 1.) NaHMDS / 1.) THF, 0 deg C, 0.25 h, 2.) 0 deg C, 15 min 7: 86 percent / CSA / CH2Cl2; methanol / 1.) 0 deg C, 1 h, 2.) 25 deg C, 0.5 h 8: 82 percent / SO3*pyridine, DMSO, Et3N / CH2Cl2 / 0.5 h / 25 °C 9: LDA / tetrahydrofuran / 1.) -78 to -40 deg C, 0.5 h, 2.) -78 deg C 10: 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 11: K2CO3 / methanol / 0.25 h / 25 °C 12: 79 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 13: 1.) 2,4,6-trichlorobenzoylchloride, Et3N, 2.) 4-DMAP / 1.) THF, 25 deg C, 15 min, 2.) toluene, 25 deg C, 0.5 h 14: 92 percent / CF3COOH / CH2Cl2 / 1 h / 0 °C View Scheme

sodium tetrahydroborate in methanol T=0°C; 0.25 h;