1: diisobutylaluminium hydride 2: oxalic acid / tetrahydrofuran / Linde 4A molecular sieves 3: 82 percent / 1.) titanium tetrachloride, 2,4,6-trimethylpyridine, 2.) 1 M hydrochloric acid / CH2Cl2 / 1.) -78 degC, 5 min., 2.) -78 degC to r.t. 4: pyridinium chlorochromate / CH2Cl2 / 18 h / 25 °C 5: 7.5 M KOH / tetrahydrofuran; methanol; H2O / 48 h / 25 °C 6: 96 percent / 10percent DMAP / pyridine / 3 h / 70 °C 7: 89 percent / H2 / Lindlar catalyst 8: 72 percent / BF3*Et2O 9: H2 / PtO2 10: KOH / tetrahydrofuran; methanol; H2O / 48 h / 25 °C View Scheme

View Scheme

Multistep reaction;

diisobutylaluminium hydride