potassium carbonate in acetone 36 h; Heating;

2: NH2OH*HCl / 0.67 h 3: 80 percent / Na / pentan-1-ol / 80 °C / Heating 4: 1.) NEt3, ethylchloroformate / 1.) DMF, 2 deg C, 0.5 h; 2.) DMF, 12 h, RT 5: 93 percent / maleic acid, H2 / 10percent Pd/C / aq. ethanol / 7 h / Ambient temperature 6: 77 percent / K2CO3 / acetone / 36 h / Heating View Scheme

1: NH2OH*HCl / 0.67 h 2: 80 percent / Na / pentan-1-ol / 80 °C / Heating 3: 1.) NEt3, ethylchloroformate / 1.) DMF, 2 deg C, 0.5 h; 2.) DMF, 12 h, RT 4: 93 percent / maleic acid, H2 / 10percent Pd/C / aq. ethanol / 7 h / Ambient temperature 5: 77 percent / K2CO3 / acetone / 36 h / Heating View Scheme

1: 1.) NEt3, ethylchloroformate / 1.) DMF, 2 deg C, 0.5 h; 2.) DMF, 12 h, RT 2: 93 percent / maleic acid, H2 / 10percent Pd/C / aq. ethanol / 7 h / Ambient temperature 3: 77 percent / K2CO3 / acetone / 36 h / Heating View Scheme

1: 80 percent / Na / pentan-1-ol / 80 °C / Heating 2: 1.) NEt3, ethylchloroformate / 1.) DMF, 2 deg C, 0.5 h; 2.) DMF, 12 h, RT 3: 93 percent / maleic acid, H2 / 10percent Pd/C / aq. ethanol / 7 h / Ambient temperature 4: 77 percent / K2CO3 / acetone / 36 h / Heating View Scheme

1: 93 percent / maleic acid, H2 / 10percent Pd/C / aq. ethanol / 7 h / Ambient temperature 2: 77 percent / K2CO3 / acetone / 36 h / Heating View Scheme