hydrogen; palladium in methanol; water T=25°C; Hydrogenolysis; P=2574.28 Torr; 4 h;

1: With zinc(II) tetrahydroborate in tetrahydrofuran; diethyl ether T=-78°C; 1 h; 2: With hydrogenchloride in ethyl acetate T=20°C; 2.5 h; 3: With hydrogen; palladium on activated charcoal in methanol T=20°C; P=760 Torr; 2.5 h;

hydrogenchloride T=20°C; 16 h;

1: activated Al2O3 / 24 h / -20 °C 2: H2 / Raney-Ni / methanol / 16 h / 20 °C 3: 185 mg / aq. NaHCO3 / ethyl acetate / 2 h / 20 °C 4: 87 percent / TsOH / toluene / 5 h / 50 °C 5: 89 percent / MeONa / methanol / 24 h / 20 °C 6: 95 percent / N-ethylmorpholine; isobutyl chloroformate / tetrahydrofuran / 1 h / -5 - 20 °C 7: 82 percent / TsOH / methanol / 24 h / 20 °C 8: 86 percent / aq. HCl / 16 h / 20 °C View Scheme

1: H2 / Raney-Ni / methanol / 16 h / 20 °C 2: 185 mg / aq. NaHCO3 / ethyl acetate / 2 h / 20 °C 3: 87 percent / TsOH / toluene / 5 h / 50 °C 4: 89 percent / MeONa / methanol / 24 h / 20 °C 5: 95 percent / N-ethylmorpholine; isobutyl chloroformate / tetrahydrofuran / 1 h / -5 - 20 °C 6: 82 percent / TsOH / methanol / 24 h / 20 °C 7: 86 percent / aq. HCl / 16 h / 20 °C View Scheme

1: 96 percent / tetrabutylammonium fluoride / tetrahydrofuran / 0.33 h / 0 °C 2: H2 / Pd/C / methanol / 2 h / atmospheric pressure View Scheme

hydrogenchloride; sodium hydroxide 1) EtOH, reflux;

1: 95 percent / N-ethylmorpholine; isobutyl chloroformate / tetrahydrofuran / 1 h / -5 - 20 °C 2: 82 percent / TsOH / methanol / 24 h / 20 °C 3: 86 percent / aq. HCl / 16 h / 20 °C View Scheme

1: 95 percent / N-ethylmorpholine; isobutyl chloroformate / tetrahydrofuran / 1 h / -5 - 20 °C 2: 82 percent / TsOH / methanol / 24 h / 20 °C 3: 86 percent / aq. HCl / 16 h / 20 °C View Scheme

1: 82 percent / TsOH / methanol / 24 h / 20 °C 2: 86 percent / aq. HCl / 16 h / 20 °C View Scheme