hydrazine hydrate in ethanol 1.) reflux, 2 h; 2.) room temperature, 24 h.;

1: 75 percent / dicyclohexylcarbodiimide / dioxane; dimethylformamide / 1.) 0 deg C, 27 h; 2.) room temperature, 24 h. 2: 65 percent / hydrazine hydrate / ethanol / 1.) reflux, 2 h; 2.) room temperature, 24 h. View Scheme

1: 75 percent / dicyclohexylcarbodiimide / dioxane; dimethylformamide / 1.) 0 deg C, 27 h; 2.) room temperature, 24 h. 2: 65 percent / hydrazine hydrate / ethanol / 1.) reflux, 2 h; 2.) room temperature, 24 h. View Scheme