1: With oxalyl dichloride; dimethyl sulfoxide in dichloromethane T=-78 - 20°C; 1 h; 2: With triethylamine in dichloromethane T=-78°C;

1: With diisobutylaluminium hydride in n-heptane; toluene T=20°C; 1 h; 2: With sulfuric acid in n-heptane; water; toluene 18 h;

1: tetrahydrofuran / 48 h / 20 °C 2: lithium aluminium tetrahydride / tetrahydrofuran / 3 h / |Reflux; |Cooling 3: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 1 h / -78 °C View Scheme

1: lithium aluminium tetrahydride / tetrahydrofuran / 3 h / |Reflux; |Cooling 2: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 1 h / -78 °C View Scheme

1: tetrahydrofuran / 48 h / 20 °C 2: lithium aluminium tetrahydride / tetrahydrofuran / 3 h / |Reflux; |Cooling 3: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 1 h / -78 °C View Scheme