1: 28 percent / LDA / tetrahydrofuran / 1.) 30 min, -78 deg C, 2.) 30 min, 0 deg C 2: Br2 / tetrahydrofuran; CHCl3 / 0.75 h / -78 °C 3: NaBH4 / ethanol; tetrahydrofuran; CHCl3 / -78 °C 4: HgCl2, CaCO3 / acetonitrile; H2O / 48 h / Ambient temperature View Scheme

1: 28 percent / LDA / tetrahydrofuran / 1.) 30 min, -78 deg C, 2.) 30 min, 0 deg C 2: Br2 / tetrahydrofuran; CHCl3 / 0.75 h / -78 °C 3: NaBH4 / ethanol; tetrahydrofuran; CHCl3 / -78 °C 4: HgCl2, CaCO3 / acetonitrile; H2O / 48 h / Ambient temperature 5: pyridine View Scheme

1: 28 percent / LDA / tetrahydrofuran / 1.) 30 min, -78 deg C, 2.) 30 min, 0 deg C 2: pyridine 3: 82 percent / SO2Cl2 / CH2Cl2 / 2 h / Heating 4: H2 / 10percent Pd/C / methanol / 20 h / Ambient temperature 5: CrO3 / acetone / 0.33 h / Ambient temperature View Scheme

1: 28 percent / LDA / tetrahydrofuran / 1.) 30 min, -78 deg C, 2.) 30 min, 0 deg C 2: pyridine 3: 82 percent / SO2Cl2 / CH2Cl2 / 2 h / Heating 4: H2 / 10percent Pd/C / methanol / 20 h / Ambient temperature View Scheme

1: 28 percent / LDA / tetrahydrofuran / 1.) 30 min, -78 deg C, 2.) 30 min, 0 deg C 2: pyridine 3: 18 percent / 3percent H2SO4, N-chlorosuccinimide / 3 h / on an ice bath View Scheme