O-lt;cyano(ethoxycarbonyl)methylenaminogt;-N,N,N',N'-tetramethyluronium tetrafluoroborate; N-ethyl-N,N-diisopropylamine in N,N-dimethyl-formamide T=10 - 20°C; 2.33333 h;

vanadium(III) chloride; zinc in tetrahydrofuran 1 h; Heating;

1-hydroxybenzotriazol-hydrate; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine in N,N-dimethyl-formamide 12 h;

in tetrahydrofuran 24 h;

1: 1.) H2SO4, 2.) 70 percent aq. AcOH / 1.) 23 deg C, 24 h, 2.) 40 deg C, 2 h 2: CHCl3 / 3 h / 23 °C 3: sodium methoxide / tetrahydrofuran / 4 h / 23 °C 4: 82 percent / CuI / tetrahydrofuran / 3 h / -40 to 0 deg C 5: triphenylphosphine, diethyl azodicarboxylate, diphenylphosphoryl azide / toluene / 12 h / 0 to 23 deg C 6: 40 percent aq. acetic acid / 3 h / 90 °C 7: hydrogen / 10 percent Pd/charcoal / ethyl acetate; methanol / atmospheric pressure 8: 82 percent / N-ethyl-N'-(dimethylaminopropyl)carbodiimide hydrochloride, triethylamine, 1-hydroxybenzotriazole hydrate / dimethylformamide / 12 h View Scheme

1: 82 percent / CuI / tetrahydrofuran / 3 h / -40 to 0 deg C 2: triphenylphosphine, diethyl azodicarboxylate, diphenylphosphoryl azide / toluene / 12 h / 0 to 23 deg C 3: 40 percent aq. acetic acid / 3 h / 90 °C 4: hydrogen / 10 percent Pd/charcoal / ethyl acetate; methanol / atmospheric pressure 5: 82 percent / N-ethyl-N'-(dimethylaminopropyl)carbodiimide hydrochloride, triethylamine, 1-hydroxybenzotriazole hydrate / dimethylformamide / 12 h View Scheme

1: CHCl3 / 3 h / 23 °C 2: sodium methoxide / tetrahydrofuran / 4 h / 23 °C 3: 82 percent / CuI / tetrahydrofuran / 3 h / -40 to 0 deg C 4: triphenylphosphine, diethyl azodicarboxylate, diphenylphosphoryl azide / toluene / 12 h / 0 to 23 deg C 5: 40 percent aq. acetic acid / 3 h / 90 °C 6: hydrogen / 10 percent Pd/charcoal / ethyl acetate; methanol / atmospheric pressure 7: 82 percent / N-ethyl-N'-(dimethylaminopropyl)carbodiimide hydrochloride, triethylamine, 1-hydroxybenzotriazole hydrate / dimethylformamide / 12 h View Scheme

1: 86 percent / triethylamine, n-propyl phosphonic anhydride / CH2Cl2; ethyl acetate / 2 h / 0 - 20 °C 2: 90 percent / oxalyl chloride, DMSO, NEt3 / CH2Cl2 / 0.25 h / -70 °C 3: 64 percent / VCl3, zinc powder / tetrahydrofuran / 1 h / Heating View Scheme

1: 90 percent / oxalyl chloride, DMSO, NEt3 / CH2Cl2 / 0.25 h / -70 °C 2: 64 percent / VCl3, zinc powder / tetrahydrofuran / 1 h / Heating View Scheme

1: hydrogen / 10 percent Pd/charcoal / ethyl acetate; methanol / atmospheric pressure 2: 82 percent / N-ethyl-N'-(dimethylaminopropyl)carbodiimide hydrochloride, triethylamine, 1-hydroxybenzotriazole hydrate / dimethylformamide / 12 h View Scheme