Dimethylformamide → 2-Aminocarbonyl-5-nitrobenzofuran

Reaktionsgleichung

[C:1]([C:4]1[O:5][C:6]2[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[CH:9][C:7]=2[CH:8]=1)(O)=[O:2].C(Cl)Cl.C(Cl)(=O)C(Cl)=O.C[N:26](C=O)C>>[NH2:26][C:1]([C:4]1[O:5][C:6]2[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[CH:9][C:7]=2[CH:8]=1)=[O:2]

Komponenten

Edukt 4

HCID 6228Dimethylformamide

HCID 6344Dichloromethane

HCID 65578Oxalyl chloride

HCID 14771285-Nitrobenzofuran-2-carboxylic acid

Produkt 1

HCID 13829552-Aminocarbonyl-5-nitrobenzofuran

Reaktionsbedingungen

Temperatur: 10 °C

Versuchsvorschrift

A dry reaction flask equipped with a magnetic stirring bar, nitrogen inlet and rubber septum was charged with 2-carboxy-5-nitrobenzofuran (0.414 g, 2 mmol) and CH2Cl2 (100 mL). To this was added DMF (0.1 mL) followed by a slow addition of oxaloyl chloride (0.519 mL, 6 mmol) over the period of 5 minutes at 0° C. The reaction mixture was further stirred for 30 minutes by the time the formation of a clear solution was observed. The resulting clear solution was concentrated under a reduced pressure and dried under high vacuum for 30 minutes. The resulting residue was suspended in EtOAc (25 mL), cooled to 10° C., to it was added NH4OH (30% solution, 25 mL) and stirred at room temperature for 24 h. The organic phase was separated and dried over anhydrous sodium sulfate and solvent was removed to give 2-aminocarbonyl-5-nitrobenzofuran. 1H NMR (DMSO-d6): δ 8.75 (d, 1H, J=2.7 Hz), 8.28 (m, 2H), 7.86 (d, 1H, J=9.0 Hz), 7.83 (bs, 1H), 7.72 (s, 1H); LCMS: purity: 93%, MS (m/e): 206 (M+).