Potassium Carbonate → Ethyl 4-methyl-2-(2-oxoimidazolidin-1-yl)thiazole-5-carboxylate

Participants

Reaction Steps

To a solution of ethyl 2-amino-4-methylthiazole-5-carboxylate (9.31 g, 49.99 mmol) in tetrahydrofuran (200 mL) was added 2-chloroethyl isocyanate (5.50 mL, 64.0 mmol) at ambient temperature. The resulting reaction mixture was heated to reflux for 7 hours, followed by the addition of potassium carbonate (8.30 g, 60.0 mmol) and tetra-n-butylammonium iodide (0.50 g, 1.35 mmol) and the resulting mixture was heated to reflux for 23 hours. The solvent was removed in vacuo, and the residue was washed with water (200 mL) and ethyl acetate (50 mL) to afford the title compound in 71% yield (9.10 g): mp 197-199° C.; 1H NMR (300 MHz, DMSO-d6) δ 7.83 (s, 1H), 4.20-3.93 (m, 4H), 3.49-3.43 (m, 2H), 2.46 (s, 3H), 1.20 (t, J=6.9 Hz, 3H); MS (ES+) m/z 256.3 (M+1).

Provenance & Evidence