HCID 19101019, Verbindung → HCID 53683293, Verbindung
Reaktionsgleichung
[NH2:1][C:2]1[O:7][C:6]2[C:8]3[C:13]([CH:14]=[CH:15][C:5]=2[CH:4]([C:16]2[CH:21]=[CH:20][C:19]([F:22])=[C:18]([Cl:23])[CH:17]=2)[C:3]=1[C:24]#[N:25])=[CH:12][CH:11]=[CH:10][CH:9]=3>C(OCC)(OCC)OCC>[Cl:23][C:18]1[CH:17]=[C:16]([CH:4]2[C:3]([C:24]#[N:25])=[C:2]([N:1]=[CH:2][O:7][CH2:6][CH3:5])[O:7][C:6]3[C:8]4[C:13]([CH:14]=[CH:15][C:5]2=3)=[CH:12][CH:11]=[CH:10][CH:9]=4)[CH:21]=[CH:20][C:19]=1[F:22]Komponenten
3
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
2-Amino-4-(3-chloro-4-fluorophenyl)-4H-naphtho[1,2-b]pyran-3-carbonitrile (3.12 g) was heated, under reflux, in triethyl orthoformate (40 ml) for 24 hours. A fraction coming over at 80° to 140° C. was distilled off and more triethyl orthofomate (40 ml) was added, and the refluxing was continued for a further 24 hours. The solution was evaporated to dryness. The gummy residue was dissolved in chloroform and passed through a column of `flash` silica using 30% hexane in chloroform as eluant. The fractions containing product were bulked, evaporated and triturated with ethyl acetate to give white crystals of 4-(3-chloro-4-fluorophenyl)-2-ethoxymethyleneamino-4H-naphtho[1,2-b]pyran-3-carbonitrile, m.p. 146°-148° C.