formic acid; triethylamine in N,N-dimethyl-formamide

1: MeNH2*HCl, AcOK, trimethyl orthoformate / methanol / 16 h / Heating 2: NaBH4 / dimethylsulfoxide / 1 h / 20 °C View Scheme

1: NH4OAc / acetic acid 2: HCO2H, Et3N / dimethylformamide View Scheme

potassium fluoride; tetrabutyl-ammonium chloride in N,N-dimethyl-formamide 4 h;

2: 98 percent / diisobutylaluminium hydride / 0 °C View Scheme

2: 98 percent / diisobutylaluminium hydride / 0 °C 3: 81 percent / MnO2 View Scheme

1: 18 percent / tetra-n-butylammonium chloride, KF*2H2O / dimethylformamide / 4 h 2: 98 percent / di-isobutylaluminium hydride / toluene / 2 h / 0 °C 3: 81 percent / MnO2 / CH2Cl2 / 0.5 h 4: 79 percent / toluene-p-sulphonic acid monohydrate / benzene / 17 h / Heating 5: 96 percent / Zn powder / acetic acid / 1.5 h / Ambient temperature 6: 89 percent / tetrahydrofuran / 0.08 h View Scheme