1: With diMe-Imd-BH3; bis-(trifluoromethylsulphonyl)amine in 1,2-dichloro-ethane T=50°C; 24 h; Inert atmosphere; 2: With dihydrogen peroxide; sodium hydroxide in methanol; water; 1,2-dichloro-ethane T=25°C; 16 h;