Phosphorus oxychloride → HCID 89782281, compound

Participants

Reaction Steps

A slurry of 8-bromo-3-methylquinazoline-2,4(1H,3H)-dione (722b, 1.14 g, 4.47 mmol), phosphoryl trichloride (4.09 mL, 44.7 mmol), and N-ethyl-N-isopropylpropan-2-amine (3.11 mL, 17.88 mmol) was stirred at reflux for 19 h. The reaction mixture was concentrated, diluted with ice, basicified with 10 N NaOH to ˜pH 10, filtered, and washed with water to give brown solid. The solid was transferred to an Erlenmeyer flask and dissolved in DCM when a small aqueous layer formed; this was partitioned in a separatory funnel. The organic layer was partially concentrated, loaded onto the column and was purified via automated flash chromatography (silica gel) with 0-40% EtOAc in hexanes to give 8-bromo-2-chloro-3-methylquinazolin-4(3H)-one (722) (1.03 g, 3.77 mmol, 84% yield) as a light yellow solid. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 3.77 (s, 3H) 7.35 (t, J=7.92 Hz, 1H) 8.02 (dd, J=7.82, 1.37 Hz, 1H) 8.21 (dd, J=8.02, 1.37 Hz, 1H). MS (ESI, pos. ion) m/z: 273.9/275.9 (M+1).

Provenance & Evidence