sodium bis(2-methoxyethoxy)aluminium dihydride in benzene T=80°C; 10 h;

Multi-step reaction with 2 steps 1: methanesulphonic acid / acetic anhydride; 1,2-dichloro-ethane / 35 °C2: 80 percent / methanesulphonic acid / acetic anhydride; 1,2-dichloro-ethane / 35 °C  

Multi-step reaction with 4 steps 2: 77 percent / potassium carbonate / H2O; toluene; benzene / 1.) 0 deg C, 30 min; 2.) 35 deg C, 24 h3: methanesulphonic acid / acetic anhydride; 1,2-dichloro-ethane / 35 °C4: 80 percent / methanesulphonic acid / acetic anhydride; 1,2-dichloro-ethane / 35 °C