Phosphorus oxychloride → 4-Chloro-2,6-diphenylpyrimidine

Participants

Reaction Steps

Phosphorous oxychloride (9.30 mL, 99.8 mmol, 7.5 eq.) was added dropwise to 2,6-diphenyl-3H-pyrimidin-4-one (10) (3.3 g, 13.3 mmol) in a vigorous reaction. To this mixture was added slowly phosphorous pentachloride (2.77 g, 13.3 mmol, 1 eq.) and the reaction mixture was stirred at reflux for 3 hours. The reaction mixture was then quenched by pouring into ice-water, and extracted with ethyl acetate (3×150 mL). The combined organic layers were washed with water and brine, dried (MgSO4) and then concentrated to give a yellow solid. This was recrystallised from hot ethanol to give fine white needles (65%). 1H NMR δ (CDCl3): 8.60-8.18 (m, 5H, Ar), 7.63 (s, 1H, Ar), 7.51-7.57 (m, 5H, Ar).

Provenance & Evidence