反应详情

A solution of 2,4-difluororesorcinol (Compound 4, 0.20 g, 1.37 mmol) and ethyl 4-chloroacetoacetate (0.29 g, 1.75 mmol) in 2 mL methanesulfonic acid is kept at room temperature for 2.5 hours, then diluted with 25 mL water. The resulting precipitate is collected on a Buchner funnel and dried to give 134 mg of dimly fluorescent Compound 28 as a colorless powder. This product is purified further by chromatography (silica gel, ethyl acetate/hexanes): Rf =0.45 (EtOAc/hexanes 3:2); 1H NMR (CDCl3 -CD3OD) δ 7.13 (dd, 1H), 6.41 (s, 1H), 4.52 (s, 2H); 19F NMR (CDCl3 -CD3OD) Φ 136.38 (t, 1F), 153.26 (d, 1F).

1. customThe resulting precipitate is collected on a Buchner funnel
2. customdried