Triethylamine → 4-[(S)-3-tert-Butoxycarbonylaminopyrrolidin-1-yl]-2,3,6-trifluorobenzoic acid ethyl ester

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Reaction Steps

A solution of 2,3,4,6-tetrafluorobenzoic acid ethyl ester (Example 1b, 5.1 g, 22.9 mmol), triethylamine (22 mL, 157 mmol), and (S)-pyrrolidin-3-ylcarbamic acid tert-butyl ester (5.2 g, 27.9 mmol) in acetonitrile (60 mL) is stirred at room temperature for 64 hours. The mixture is concentrated in vacuo and the residue dissolved in chloroform, washed with NaHCO3 and then brine, dried over Na2SO4, filtered, and concentrated under vacuum to afford a solid. The solid is purified by column chromatography (1:1:7 ethyl acetate/chloroform/hexanes) to afford the title compound (6.21 g). 1H NMR (CDCl3): δ 6.07 (ddd, 1H), 4.78–4.63 (bd, 1H), 4.49–4.22 (m, 3H), 3.80–3.68 (m, 1H), 3.66–3.28 (m, 3H), 2.33–2.13 (m, 1H), 2.04–1.83 (m, 1H), 1.45 (s, 9H), 1.36 (t, 3H).

Provenance & Evidence