Allyl iodide → 7-fluoro-1-(2-propen-1-yl)-2(1H)-quinoxalinone

Beteiligte Stoffe

Reaktionsschritte

A 1:2 mixture of 7-fluoro-2(1H)-quinoxalinone and 6-fluoro-2(1H)-quinoxalinone (20 g, 0.122 mol) in dry DMF (250 ml) and anhydrous potassium carbonate (50.5 g, 0.38 mol) was treated with allyl iodide (12.3 ml, 0.134 mol) and the mixture was stirred at rt for 2 hours. The reaction mixture was evaporated to dryness, water was added and the mixture was extracted (3×) with DCM, washed with water, dried (sodium sulphate) and evaporated. It was chromatographed, twice, on silica gel, eluting with 0-40% ethyl acetate-hexane. The early fractions gave 7-fluoro-1-(2-propen-1-yl)-2(1H)-quinoxalinone (4.7 g) [later fractions contained the isomeric 6-fluoro-isomer (6.7 g)].

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