triphenylphosphine; diethylazodicarboxylate in tetrahydrofuran 2 h; Ambient temperature;

1: 96 percent / NMO; water; OsO4 / toluene; 2-methyl-propan-2-ol / 1 h / 20 °C 2: 44 percent / Amano AK / various solvent(s) / 2 h / 20 °C / Enzymatic reaction 3: triethylamine / tetrahydrofuran / 0.5 h / 0 °C 4: potassium carbonate / ethanol / 6 h / 20 °C View Scheme

potassium carbonate in ethanol T=20°C; Cyclization; 6 h;

1: 60 percent / NaBH4-silica / diethyl ether / 18 h / Ambient temperature 2: 49 percent / t-butylhydroperoxide, titanium isopropoxide, diethyl L-(+)-tartrate / -20 deg C, 3 h. then room temp., 1 h. 3: 1.) NaIO4; 2.) NaHCO3 / 1.) RuCl3 / 1.) CCl4, CH3CN, H2O, room temp., 7 h.; 2.) DMF, room temp. View Scheme

1: 63 percent / SOCl2 / 18 h / from 0 deg C to room temp. 2: 60 percent / NaBH4-silica / diethyl ether / 18 h / Ambient temperature 3: 49 percent / t-butylhydroperoxide, titanium isopropoxide, diethyl L-(+)-tartrate / -20 deg C, 3 h. then room temp., 1 h. 4: 1.) NaIO4; 2.) NaHCO3 / 1.) RuCl3 / 1.) CCl4, CH3CN, H2O, room temp., 7 h.; 2.) DMF, room temp. View Scheme

1: 75 percent 2: 96 percent / NMO; water; OsO4 / toluene; 2-methyl-propan-2-ol / 1 h / 20 °C 3: 44 percent / Amano AK / various solvent(s) / 2 h / 20 °C / Enzymatic reaction 4: triethylamine / tetrahydrofuran / 0.5 h / 0 °C 5: potassium carbonate / ethanol / 6 h / 20 °C View Scheme

1: 44 percent / Amano AK / various solvent(s) / 2 h / 20 °C / Enzymatic reaction 2: triethylamine / tetrahydrofuran / 0.5 h / 0 °C 3: potassium carbonate / ethanol / 6 h / 20 °C View Scheme

1: triethylamine / tetrahydrofuran / 0.5 h / 0 °C 2: potassium carbonate / ethanol / 6 h / 20 °C View Scheme

1: 93 percent / NaH / tetrahydrofuran / 24 h / Ambient temperature 2: 1.) NaH 3: 100 percent / aq. KOH / methanol / 5 h / Heating 4: 83 percent / diethyl phosphorocyanidate, Et3N / dimethylformamide / 2 h / 0 °C 5: 100 percent / aq. KOH / methanol / 10 h / Heating 6: 87 percent / NBS / dimethylformamide / 24 h / Ambient temperature 7: 6N aq. HCl / 12 h / Heating 8: diethyl ether 9: 98 percent / K2CO3 / 6 h / Ambient temperature 10: 94 percent / Ph3P, diethylazodicarboxylate / tetrahydrofuran / 2 h / Ambient temperature View Scheme

1: 1.) NaH 2: 100 percent / aq. KOH / methanol / 5 h / Heating 3: 83 percent / diethyl phosphorocyanidate, Et3N / dimethylformamide / 2 h / 0 °C 4: 100 percent / aq. KOH / methanol / 10 h / Heating 5: 87 percent / NBS / dimethylformamide / 24 h / Ambient temperature 6: 6N aq. HCl / 12 h / Heating 7: diethyl ether 8: 98 percent / K2CO3 / 6 h / Ambient temperature 9: 94 percent / Ph3P, diethylazodicarboxylate / tetrahydrofuran / 2 h / Ambient temperature View Scheme