in diethyl ether; N,N-dimethyl-formamide

1: oxalyl chloride / 3 h 2: 70 percent / dimethylformamide; diethyl ether View Scheme

1: t-BuOK / dimethylformamide / 15 h / Ambient temperature 2: thionyl chloride / 1.) RT, 8 h, 2.) 100 deg C, 0.5 h 3: diethyl ether / 1.) room temp., 2 h, 2.) reflux, 2 h View Scheme

1: ammonium formate / 3 h / 180 °C 2: diethyl ether / 1.) room temp., 2 h, 2.) reflux, 2 h View Scheme

1: conc. H2SO4 / Heating 2: pyridinium chlorochromate (PCC), sodium acetate / CH2Cl2 / 1.5 h / Ambient temperature 3: 1.) t-BuOK / 1.) DMF, RT, 5 min, 2.) a) RT, 20 h, b) 90 deg C, 1 h 4: aq. KOH / ethanol / 1 h / Heating 5: thionyl chloride / 1.) RT, 18 h, 2.) 100 deg C, 30 min 6: diethyl ether / 72 h / Ambient temperature View Scheme

1: 1.) t-BuOK / 1.) DMF, RT, 5 min, 2.) a) RT, 20 h, b) 90 deg C, 1 h 2: aq. KOH / ethanol / 1 h / Heating 3: thionyl chloride / 1.) RT, 18 h, 2.) 100 deg C, 30 min 4: diethyl ether / 72 h / Ambient temperature View Scheme

1: pyridinium chlorochromate (PCC), sodium acetate / CH2Cl2 / 1.5 h / Ambient temperature 2: 1.) t-BuOK / 1.) DMF, RT, 5 min, 2.) a) RT, 20 h, b) 90 deg C, 1 h 3: aq. KOH / ethanol / 1 h / Heating 4: thionyl chloride / 1.) RT, 18 h, 2.) 100 deg C, 30 min 5: diethyl ether / 72 h / Ambient temperature View Scheme

1: aq. KOH / ethanol / 1 h / Heating 2: thionyl chloride / 1.) RT, 18 h, 2.) 100 deg C, 30 min 3: diethyl ether / 72 h / Ambient temperature View Scheme

hydrogen; palladium on activated charcoal in ethanol P=760 Torr; 4 h;