1: BF3*Et2O / CH2Cl2 / 0.75 h 2: 90 percent / H2 / Raney Ni / ethyl acetate; methanol / 4 h / Ambient temperature 3: LDA / 0.08 h / -78 °C 4: 1) TFAA, DMSO 2) K-selectride / 1) 16h, 0 deg C; 2) Et2O, 0.5h 5: 1) imidazole 2) Jones reagent / 1) DMF View Scheme