1: 87.5 percent / pyridine / 32 h / 20 °C 2: 67.7 percent / AgSO3CF3, Me2NCONMe2 / CH2Cl2 / 22 h / 20 °C / 6 added in two portions. Two-thirds: -10 to -15 deg C, 20 deg C, 6 h; the rest: -10 to -15 deg C, 20 deg C, 16 h 3: 79.1 percent / NaOMe / methanol / 16 h / 20 °C 4: 87.2 percent / H2 / 10percent Pd/C / ethanol / 1) 45 deg C, 3 h; 2) 25 deg C, 16 h View Scheme

1: 54.4 percent / AgSO3CF3, Me2NCONMe2 / CH2Cl2 / 21 h / -5 - 25 °C 2: 90.7 percent / AgSO3CF3, Me2NCONMe2 / CH2Cl2 / 19 h / -15 - 20 °C 3: 83.2 percent / NaOMe / methanol; tetrahydrofuran / 16 h / 20 °C 4: H2 / Pd-C / ethanol; H2O / 20 deg C, 16 h; 50 deg C, 2 h View Scheme

1: 52 percent / AgOSO2CF3, s-collidine / 1,2-dichloro-ethane / 14 h / 20 - 25 °C 2: n-BuNH2 / methanol / 24 h / Heating 3: methanol / 14 h / 20 - 25 °C 4: H2 / 10percent Pd-C / dimethylformamide; H2O / 6 h / 40 °C View Scheme