1: 90 percent / 3.5 h / 190 °C 2: 82 percent / LiAlH4 / diethyl ether / 0 - 20 °C 3: 92 percent / imidazole / dimethylformamide / 24 h / 20 °C 4: O3; NaOH / methanol; CH2Cl2 / -78 °C 5: 0.98 g / methanol / 0 - 20 °C 6: 84 percent / TBAF / tetrahydrofuran / 0 - 20 °C View Scheme