palladium 10 on activated carbon; hydrogen in benzene T=20°C; 4 h;

water; acetic acid in tetrahydrofuran T=40°C; 24 h;

1: 1) titanium tetraisopropoxide, L-(+)-diethyltartrate, molecular sieves 4A, t-butyl hydroperoxide, 2) Me2S, aq. NaF / 1) CH2Cl2, ClCH2CH2Cl, -23 deg C, 2 h, 2) r.t., 24 h 2: 1) (COCl)2/DMSO, 2) Et3N / 1) 1) CH2Cl2, -78 deg C, 30 min, 2) r.t., 1 h 3: tetrahydrofuran / 2 h / 0 °C 4: formic acid, Et3N / Pd2(dba)3CHCl3-P(OMe)3 / dioxane / 2 h / Ambient temperature; var. phosphorus ligands; var. times; var. concentrations of formic acid 5: 83 percent / H2 / 5percent Pd/C / methanol / 24 h / Ambient temperature 6: 11 percent / p-TsOH / tetrahydrofuran; H2O / 5 h / 50 °C View Scheme

1: 1) (COCl)2/DMSO, 2) Et3N / 1) 1) CH2Cl2, -78 deg C, 30 min, 2) r.t., 1 h 2: tetrahydrofuran / 2 h / 0 °C 3: formic acid, Et3N / Pd2(dba)3CHCl3-P(OMe)3 / dioxane / 2 h / Ambient temperature; var. phosphorus ligands; var. times; var. concentrations of formic acid 4: 83 percent / H2 / 5percent Pd/C / methanol / 24 h / Ambient temperature 5: 11 percent / p-TsOH / tetrahydrofuran; H2O / 5 h / 50 °C View Scheme

1: formic acid, Et3N / Pd2(dba)3CHCl3-P(OMe)3 / dioxane / 2 h / Ambient temperature; var. phosphorus ligands; var. times; var. concentrations of formic acid 2: 83 percent / H2 / 5percent Pd/C / methanol / 24 h / Ambient temperature 3: 11 percent / p-TsOH / tetrahydrofuran; H2O / 5 h / 50 °C View Scheme

toluene-4-sulfonic acid in tetrahydrofuran; water T=50°C; 5 h; Yields of byproduct given;

1: 98.5 percent / LAH / diethyl ether / 2 h / Ambient temperature 2: 1) NaH / 1) THF, reflux, 1.5 h, 2) THF, reflux, several hours 3: TsOH, MeOH / 0.5 h / Ambient temperature 4: 52 percent / Ph3P, EtO2CN=NCO2Et / tetrahydrofuran / 24 h / Ambient temperature 5: 95 percent / N KOH aq / tetrahydrofuran; ethanol / 1 h / Ambient temperature 6: imidazole / dimethylformamide / Ambient temperature; several hours 7: 96.7 percent / H2 / 10percent Pd-C / ethanol 8: pyridine / 0 °C / several hours 9: NaI, NaHCO3 / acetone / Heating; several hours 10: 1) LDA, / 1) THF-hexane-HMPA, -55 deg C, 30 min, 2) THF-hexane-HMPA, -60 to -5 deg C, 3 h 11: 37 percent / AcOH, H2O / tetrahydrofuran / 24 h / 40 °C View Scheme

1: 1) NaH / 1) THF, reflux, 1.5 h, 2) THF, reflux, several hours 2: TsOH, MeOH / 0.5 h / Ambient temperature 3: 52 percent / Ph3P, EtO2CN=NCO2Et / tetrahydrofuran / 24 h / Ambient temperature 4: 95 percent / N KOH aq / tetrahydrofuran; ethanol / 1 h / Ambient temperature 5: imidazole / dimethylformamide / Ambient temperature; several hours 6: 96.7 percent / H2 / 10percent Pd-C / ethanol 7: pyridine / 0 °C / several hours 8: NaI, NaHCO3 / acetone / Heating; several hours 9: 1) LDA, / 1) THF-hexane-HMPA, -55 deg C, 30 min, 2) THF-hexane-HMPA, -60 to -5 deg C, 3 h 10: 37 percent / AcOH, H2O / tetrahydrofuran / 24 h / 40 °C View Scheme

1: 52 percent / Ph3P, EtO2CN=NCO2Et / tetrahydrofuran / 24 h / Ambient temperature 2: 95 percent / N KOH aq / tetrahydrofuran; ethanol / 1 h / Ambient temperature 3: imidazole / dimethylformamide / Ambient temperature; several hours 4: 96.7 percent / H2 / 10percent Pd-C / ethanol 5: pyridine / 0 °C / several hours 6: NaI, NaHCO3 / acetone / Heating; several hours 7: 1) LDA, / 1) THF-hexane-HMPA, -55 deg C, 30 min, 2) THF-hexane-HMPA, -60 to -5 deg C, 3 h 8: 37 percent / AcOH, H2O / tetrahydrofuran / 24 h / 40 °C View Scheme

1: imidazole / dimethylformamide / Ambient temperature; several hours 2: 96.7 percent / H2 / 10percent Pd-C / ethanol 3: pyridine / 0 °C / several hours 4: NaI, NaHCO3 / acetone / Heating; several hours 5: 1) LDA, / 1) THF-hexane-HMPA, -55 deg C, 30 min, 2) THF-hexane-HMPA, -60 to -5 deg C, 3 h 6: 37 percent / AcOH, H2O / tetrahydrofuran / 24 h / 40 °C View Scheme