diisobutylaluminium hydride in hexane; dichloromethane T=-78°C;

lithium aluminium tetrahydride in tetrahydrofuran 2 h; Heating;

1: DMSO; oxalyl chloride; Et3N / CH2Cl2 / -78 - 20 °C 2: CH2Cl2 / 36 h / 20 °C 3: 92 percent / diisobutylaluminum hydride / tetrahydrofuran; toluene / 3 h / -20 °C View Scheme

1: CH2Cl2 / 36 h / 20 °C 2: 92 percent / diisobutylaluminum hydride / tetrahydrofuran; toluene / 3 h / -20 °C View Scheme

1.1: NaH / tetrahydrofuran; dimethylsulfoxide / 0.5 h / 20 °C 1.2: 78 percent / tetrabutylammonium iodide / tetrahydrofuran; dimethylsulfoxide / 60 °C 2.1: DMSO; oxalyl chloride; Et3N / CH2Cl2 / -78 - 20 °C 3.1: CH2Cl2 / 36 h / 20 °C 4.1: 92 percent / diisobutylaluminum hydride / tetrahydrofuran; toluene / 3 h / -20 °C View Scheme

1: 1.) NaH / 1.) THF, RT, 4 h, 2.) THF, overnight 2: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 1 h, 2.) THF, hexane, from -78 deg C to RT, overnight 3: 76 percent / NaAlH2(OCH2CH2OEt)2 (Red-Al) / tetrahydrofuran; toluene / 0 °C View Scheme

1: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 1 h, 2.) THF, hexane, from -78 deg C to RT, overnight 2: 76 percent / NaAlH2(OCH2CH2OEt)2 (Red-Al) / tetrahydrofuran; toluene / 0 °C View Scheme

1: 69 percent / Ag2O / dimethylformamide / 48 h / Ambient temperature 2: 95 percent / DIBAL-H / CH2Cl2; hexane / -78 °C View Scheme

1.1: n-BuLi / tetrahydrofuran; petroleum ether / -78 - 0 °C 1.2: HMPA / tetrahydrofuran; petroleum ether / -50 °C 1.3: 70 percent / tetrahydrofuran; petroleum ether / 8 h / -50 - 20 °C 2.1: 96 percent / LiAlH4 / tetrahydrofuran / 2 h / Heating View Scheme

Multistep reaction;