1: 1.) SOCl2, 2.) NaBH4 / 1) reflux, 1 h; 2) CH2Cl2, EtOH, 10 deg C, 1 h 2: 82 percent / 4 Anstroem molecular sieves, diisopropyl L-tartrate, Ti(OPr-i)4, t-BuOOH / CH2Cl2; 2,2,4-trimethyl-pentane / 4 h / -20 °C 3: 1.) NaH, 2.) ZnCl2, 3.) 4 Angstroem molecular sieves / 1) THF, 5 deg C, 30 min; 2) THF, 5 deg C, 30 min; 3) THF, 55 deg C, 16 h 4: 1.) Et3N, MeSO2Cl, 2.) aq. NaOH / 1) pyridine, 5 deg C, 2 h; 2) pyridine, pH 12.5 5: CF3CHCF2NEt2 / CH2Cl2 / 2 h / 100 °C 6: KOAc / methanol; propan-2-ol; H2O / 3 h / Heating; pH 5 View Scheme

sodium tetrahydroborate; thionyl chloride 1) reflux, 1 h; 2) CH2Cl2, EtOH, 10 deg C, 1 h; Yield given. Multistep reaction;