1: 92 percent / Et3N / dimethylformamide / 44 h / 23 °C 2: 97 percent / N,N-diisopropylethylamine / CH2Cl2 / 19 h / 23 °C 3: 1.) lithium diisopropylamide / 1.) THF, -78 gradC, 30 min. 2.) CH2Cl2, from -78 gradC to 23 gradC, 1.5 h. 4: titanium tetrachloride / CH2Cl2 / 1 h / 0 °C 5: 1.) 6N HCl, HOAc 2.) propylene oxide / 1.) 100 gradC, 3 h. 2.) EtOH View Scheme