Phosphorus oxychloride → Methyl 5-chloro-3-(methylthio)pyrimido[4,5-c]quinoline-8-carboxylate

Participants

Reaction Conditions

Reaction Steps

Methyl 3-(methylthio)-5-oxo-5,6-dihydropyrimido[4,5-c]quinoline-8-carboxylate (1.0 eq, 279 mg, 0.926 mmol) was suspended in toluene (2 ml). POCl3 (2 ml) and DIEA (0.5 ml) were added and the mixture stirred at 120° C. for 5 hours. The volatiles were removed in vacuo and CH2Cl2 was added. The organic phase was washed with saturated aqueous sodium bicarbonate, washed with water and dried over Na2SO4. The solution was filtered through a pad of celite and the solvents removed in vacuo. The material was triturated in hexanes and AcOEt, filtered and dried to provide methyl 5-chloro-3-(methylthio)pyrimido[4,5-c]quinoline-8-carboxylate as a beige solid (184 mg, 63% yield). LCMS (ES): >95% pure, m/z 320 [M+1]+, 322 [M+3]+.

Provenance & Evidence