Phosphorus oxychloride → HCID 59380503, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of (4-oxo-3,4-dihydro-benzo[4,5]thieno[2,3-d]pyrimidin-7-yl)-acetic acid ethyl ester (1.78 g, 6.17 mmol, 1 equiv, from step 3) in toluene (15 mL) were added diisopropylethylamine (1.18 mL, 6.79 mmol, 1.1 equiv) and phosphorous oxychloride (0.63 mL, 6.79 mmol, 1.1 equiv) at 0° C. under argon. The flask was equipped with a reflux condenser and heated at 80° C. for 5 h. The reaction mixture was cooled to rt and quenched with ice/saturated aqueous NaHCO3. The resulting mixture was extracted with EtOAc (3×80 mL). The combined organic layers was dried over sodium sulfate and concentrated in vacuo. The crude material was purified by flash chromatography (20% EtOAc/hexane) to yield 1.12 g (3.6 mmol, 56%) of a light yellow solid. 1H-NMR (DMSO-d6) δ 9.01 (s, 1H), 8.64 (d, J=8.6 Hz, 1H), 8.15 (s, 1H), 7.61 (d, J=8.6 Hz, 1H), 4.10 (q, 2H), 3.92 (s, 2H), 1.20 (t, 3H), LCMS RT=3.19 min, [M+H]+=307

Provenance & Evidence