1: 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride, 1-hydroxybenzotriazole / CH2Cl2 / 24 h / Ambient temperature 2: 1.) aq. HCOOH / 1.) room temp., 2 h, 2.) 2-butanol, xylene, heating, 4 h View Scheme

1: 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride, 1-hydroxybenzotriazole / CH2Cl2 / 24 h / Ambient temperature 2: 1.) aq. HCOOH / 1.) room temp., 2 h, 2.) 2-butanol, xylene, heating, 4 h View Scheme

1: HCl / 4 h / Heating 2: 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride, 1-hydroxybenzotriazole / CH2Cl2 / 24 h / Ambient temperature 3: 1.) aq. HCOOH / 1.) room temp., 2 h, 2.) 2-butanol, xylene, heating, 4 h View Scheme

formic acid 1.) room temp., 2 h, 2.) 2-butanol, xylene, heating, 4 h; Multistep reaction;