1: Et3N / CH2Cl2 / -30 °C 2: 89 percent / NaN3 / dimethylformamide / 50 °C 3: Pseudomonas capacia / Microbiological reaction 4: PPh3; H2O / tetrahydrofuran / 55 °C 5: Et3N / 20 °C 6: 88 percent / imidazole / 20 °C 7: 92 percent / NaH / dimethylformamide / 20 °C 8: 95 percent / Grubb's catalyst / CH2Cl2 / Heating 9: 96 percent / nBu4NF / tetrahydrofuran / 20 °C 10: 72 percent / m-chloroperbenzoic acid / CH2Cl2 / Heating 11: KOH (1 percent) / Heating View Scheme