1: 96 percent / p-toluenesulfonic acid / 2 h / Ambient temperature 2: 93 percent / K2CO3 / methanol / 1 h / Ambient temperature View Scheme

1: 85 percent / 18 M H2SO4 / tetrahydrofuran; H2O / 30 h / 0 °C 2: 96 percent / p-toluenesulfonic acid / 2 h / Ambient temperature 3: 93 percent / K2CO3 / methanol / 1 h / Ambient temperature View Scheme

2: 85 percent / 18 M H2SO4 / tetrahydrofuran; H2O / 30 h / 0 °C 3: 96 percent / p-toluenesulfonic acid / 2 h / Ambient temperature 4: 93 percent / K2CO3 / methanol / 1 h / Ambient temperature View Scheme

1: p-TsOH / acetone / 0.5 h / Ambient temperature 2: (n-Bu)3P / tetrahydrofuran / 3.5 h / Ambient temperature 3: 81 percent / 35percent aq. H2O2 / tetrahydrofuran / 1.) -5 deg C, 1 h; 2.) rt, 1.5 h 4: 87 percent / C5H5NHBr3 / tetrahydrofuran / 1.) 0 deg C, 30 min; 2.) rt, 2.5 h 5: 72 percent / NaNH2 / liquid ammonia; diethyl ether / 1.) -50 deg C, 30 min; 2.) -27 deg C, 3.5 h 6: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 7: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 8: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 9: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: (n-Bu)3P / tetrahydrofuran / 3.5 h / Ambient temperature 2: 81 percent / 35percent aq. H2O2 / tetrahydrofuran / 1.) -5 deg C, 1 h; 2.) rt, 1.5 h 3: 87 percent / C5H5NHBr3 / tetrahydrofuran / 1.) 0 deg C, 30 min; 2.) rt, 2.5 h 4: 72 percent / NaNH2 / liquid ammonia; diethyl ether / 1.) -50 deg C, 30 min; 2.) -27 deg C, 3.5 h 5: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 6: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 7: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 8: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 2: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 3: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 4: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: 87 percent / C5H5NHBr3 / tetrahydrofuran / 1.) 0 deg C, 30 min; 2.) rt, 2.5 h 2: 72 percent / NaNH2 / liquid ammonia; diethyl ether / 1.) -50 deg C, 30 min; 2.) -27 deg C, 3.5 h 3: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 4: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 5: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 6: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: 72 percent / NaNH2 / liquid ammonia; diethyl ether / 1.) -50 deg C, 30 min; 2.) -27 deg C, 3.5 h 2: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 3: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 4: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 5: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: LiAlH4 / tetrahydrofuran / 30 min at 0 deg C, then 1 h at room temp., then 30 min reflux 2: p-TsOH / acetone / 0.5 h / Ambient temperature 3: (n-Bu)3P / tetrahydrofuran / 3.5 h / Ambient temperature 4: 81 percent / 35percent aq. H2O2 / tetrahydrofuran / 1.) -5 deg C, 1 h; 2.) rt, 1.5 h 5: 87 percent / C5H5NHBr3 / tetrahydrofuran / 1.) 0 deg C, 30 min; 2.) rt, 2.5 h 6: 72 percent / NaNH2 / liquid ammonia; diethyl ether / 1.) -50 deg C, 30 min; 2.) -27 deg C, 3.5 h 7: 1) n-BuLi / 1) hexane, THF, -5 deg C, 45 min; 2) THF, -60 deg C, 1 h, then room temp. 8: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 9: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 10: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme

1: 1) NaOH / 1) MeOH, room temp., 30 min; 2) MeOH, room temp., 4 h 2: 1) CuI / 1) THF, -65 deg C, 15 min; 2) THF, -65 deg C, 3 h 3: 90 percent / LiAlH4 / diethyl ether / 3 h / 0 °C View Scheme