Trifluoroacetic acid → Ethyl 2-(3,4-dichloroanilino)acetate

Participants

Reaction Steps

3,4-Dichloroaniline (100 g, 0.617 mol), ethyl bromoacetate (68.4 mL, 0.617 mol), and diisopropylethylamine (129.0 mL, 0.740 mol) were combined in 300 mL of dry NMP and stirred at room temperature for 18 h. HPLC (Eclipse XDB-C18, 4.6×250 mm, 5 micron, 1-99% CH3CN/H2O with 0.1% trifluoroacetic acid) after 18 h at room temperature showed that most of the starting material (Rt=5.2 min) was consumed and that a new peak had formed (Rt=7.9 min). The reaction was heated to 90° C. for 1 h, at which point HPLC indicated that conversion was complete. The reaction was allowed to cool to room temperature and then poured onto 2.5 L of ice, 1.5 L of water, and 240 g of NaHCO3. A tan precipitate formed immediately, the suspension was stirred vigorously for 10 minutes and then filtered through a fritted glass funnel. The tan solid was air-dried for 20 h in a crystallizing dish and then transferred to a 1 L flask and dried by rotary evaporation to remove the bulk of the remaining water. The tan solid was further dried under high vacuum to give 148 g (97%) of the title compound. LC/MS (APCI) m/e 248 [M+H]+.

Provenance & Evidence