Anthranilic Acid → 4-Quinazolone, 2-ethyl-3-methyl

Participants

Reaction Conditions

Reaction Steps

A mixture of anthranilic acid (13.7 g, 100 mmol), methylamine (2M solution in methanol, 100 mL, 200 mmol), triethylorthopropionate (40 mL, 200 mmol), pTSA (catalytic amount) was heated at 70° C. with stirring for 3 days. The reaction mixture was cooled to room temperature, IN NaOH solution (160 mL) was added and the mixture stirred vigourously. The resulting precipitate was filtered, washed with water and dried under high vacuum to yield the product as a fluffy white solid (13.67 g, 73%). 1H NMR (400 MHz, CDCl3) δ 1.41 (t, 3H, J=7.4 Hz), 2.87 (q, 2H, J=7.4 Hz), 3.64 (s, 3H), 7.44 (t, 1H, J=8.1 Hz), 7.65 (dd, 1H, J=8.8, 0.7 Hz), 7.72 (t, 1H, J=8.4 Hz), 8.27 (dd, 1H, J=9.2, 1.8 Hz); ESI-MS m/z 189.0 (M+1)+.

Provenance & Evidence