Acetic Anhydride → HCID 178471965, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Ethyl 2,3,4,5-tetrafluorobenzoylacetate was treated with triethyl orthofomate and acetic anhydrate, then with different aminonaphthols in the presence of pyridine to generate an aminoketoacid. The solution of ethyl 2,3,4,5-tetrafluorobenzoylacetate (1.10 g, 4.18 mmol) in triethylorthoformate (1 ml, 6.06 mmol) and acetic anhydride (1.8 ml, 19 mmol) was heated and stirred at 130° C. for 4 h. During the process, the formed ethyl acetate was removed. The mixture was then distilled under vacuum to yield an orange oil, which was dissolved in 30 ml dichloromethane. 1-aminonaphthalen-2-ol hydrogen chloride (90% pure from Aldrich) (1.36 g, 6.26 mmol), premixed with 2 equivalent of pyridine, was added to the dichloromethane solution, and the mixture was stirred overnight at 22° C. After the solvent was removed under reduced pressure, the remaining residue was absorbed on silica gel and subjected to flash column chromatography (gradient ethylacetate:hexanes=8:4) that yield a bright yellow powder (1.69 g). Yield=93%. 1H NMR (CDCl3) δ 1.02 (t, J=7.2 Hz, 3H), 4.01 (q, J=7.2 Hz, 2H), 4.10 (m, 1H), 7.34 (d, J=9.0 Hz, 1H), 7.41 (m, 1H), 7.60 (m, 2H), 7.82 (8, 2H), 7.91 (d, J=8.1 Hz, 1H), 8.54 (b, 1H).

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