trimethylsilyl trifluoromethanesulfonate in dichloromethane T=-78°C; 3 h;

1: 93 percent / CeCl3*6H2O; NaBH4 / methanol / 0.33 h / 0 °C 2: 70 percent / Me3SiOTf / CH2Cl2 / 3 h / -78 °C View Scheme

1: 1.) 1,8-diazabicyclo<5.4.0>ndec-7-ene (DBU); 2.) 3 N aq. HCl / 1.) DMSO, 80 deg C, 11 h; 2.) methanol, 30 min. 2: NaBH4 / CeCl3*7H2O / methanol / 0 °C 3: 70 percent / trimethylsilyl triflate / CH2Cl2 / 3 h / -78 °C View Scheme

tetra-n-butylammonium perchlorate; lithium perchlorate in dichloromethane Ambient temperatureelectrolysis;