trifluoroacetic acid in water; acetonitrile T=0°C;

trifluoroacetic acid in acetonitrile T=0°C; 3 h; Yields of byproduct given;

1: 1.) Na, MeOH, 2.) 2,6-lutidine, 3.) NaH 2: BF3*Et2O, TFA / CH2Cl2 / Ambient temperature 3: 100 percent / Na, MeOH View Scheme

1: bromotrimethylsilane / CH2Cl2 / 2 h / Heating 2: 90 percent / mercuric bromide, mercuric cyanide, 4A molecular sieves / acetonitrile / 1 h / Ambient temperature 3: 78 percent / 60 percent acetic acid / H2O / 0.5 h / 80 °C / Heating 4: 1.) glacial acetic acid, sodium acetate; 2.) methanol / 1.) 10 percent palladium-on-charcoal; 2.) 2 M sodium methoxide / 1.) ethanol, water, heating for 17 h at 75 deg C; 2.) 20 min View Scheme

1: bromotrimethylsilane / CH2Cl2 / 2 h / Heating 2: 67 percent / mercuric bromide, mercuric cyanide, 4A molecular sieves / acetonitrile / 1 h / Ambient temperature 3: 1.) acetic acid, sodium acetate; 2.) methanol / 1.) 10 percent palladium-on-charcoal; 2.) 2 M sodium methoxide / 1.) ethanol, water, heating for 17 h at 75 deg C; 2.) 30 min View Scheme

trimethylsilyl bromide in dichloromethane 2 h; Heating;

boron trifluoride diethyl etherate in dichloromethane T=-30°C;

in dichloromethane T=50°C; 2 h; Microwave irradiationInert atmosphereMolecular sieve; stereoselective reaction;

trimethylsilyl trifluoromethanesulfonate in dichloromethane T=-30°C; 0.0833333 h; Inert atmosphere; stereoselective reaction;

boron trifluoride diethyl etherate in dichloromethane 0.5 h; Ambient temperature;