Multi-gram Preparation of 1-(3-Dimethylamino propyl)-3-ethylurea (EDU).

1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide hydrochloride ( B 1 b ) (EDC-HCl) (Figure 1) is a widely used reagent for such organic transformations as peptide coupling, amidation, esterification, protein modification and mild oxidation of primary alcohols.[1] The advantage of B 1 b over other potentially useful reagents is that the by-product ( B 2, b EDU) produced from the reaction is water soluble and therefore easily extracted at scale. 1-(3-Dimethylamino propyl)-3-ethylurea (EDU) (2) To a stirred solution of EDC-HCl B (1) b (50.0 g, 0.261 mol) in H SB 2 sb O (100 mL), aqueous sodium hydroxide solution (500 g, 10% w/w) was added. After completion of the reaction, the reaction mass was cooled to 20-30 °C. [Extracted from the article]