1: 1.) LDA / 1.) THF, -70 deg C, 10 min, 2.) THF, -70 deg C, 30 min 2: trifluoroacetic acid / CH2Cl2 / Ambient temperature 3: 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / benzene / 8 h / Heating 4: lithium aluminum hydride / tetrahydrofuran / 1.) from -20 deg C to 10 deg C, 1 h, 2.) 10 deg C, 1 h View Scheme

1: 40 percent / NaH, MeOH / toluene / 0 - 20 °C 2: 73 percent / hydrogen / 10 percent palladium on charcoal / acetic acid / 4 h / Ambient temperature 3: 82 percent / CaCl2, NaBH4 / ethanol / 0.25 h / Ambient temperature 4: 98 percent / pyridine / 0.33 h / 0 °C 5: 90 percent / LiBEt3 / tetrahydrofuran / 1 h / Ambient temperature View Scheme