1: dimethylsulfoxide / 3 h / 80 °C 2: H2, Et3N / 10percent Pd/C / Ambient temperature 3: 1.) CF3COOH / 1.) 10 min, 2.) 0 deg C, 10 min View Scheme

1: H2, triethylamine / 10percent Pd/C / tetrahydrofuran / Ambient temperature; atmospheric pressure 2: 1) trifluoroacetic acid / 1) 30 min, 2) methylene chloride, r.t., 30 min, then 40 deg C, 1 h View Scheme

hydrogen; triethylamine; palladium on activated charcoal in tetrahydrofuran Ambient temperatureatmospheric pressure;