Triethylamine → 4-Chloro-6-fluoroquinazoline

Participants

Reaction Steps

Preparation D2, Step 2: 6-fluoroquinazolin-4-ol (1.00 g, 6.09 mmol, 1 eq.), phosphorus oxychloride (3.41 mL, 36.6 mmol, 6 eq.) and triethylamine (5.09 mL, 36.6 mmol, 6 eq.) were mixed at room temperature and then refluxed for 2 hours. Worked up by stripping 3 times from methylene chloride. The residue was dissolved in methylene chloride (25 mL) and rinsed 3 times with saturated sodium bicarbonate (25 mL) and 1× with brine (25 mL). The organic layer was dried (sodium sulfate) and stripped to give a crude oil. Purified over silica gel in 9:1 to 3:1 hexanes/ethyl acetate. Obtained 4-chloro-6-fluoroquinazoline (0.96 g) as a tan solid. Yield=86%. LCMS detects (M+H)+=183.16.

Provenance & Evidence