Nitric Acid → HCID 68285413, Verbindung
Reaktionsgleichung
S(=O)(=O)(O)O.[Br:6][C:7]1[CH:11]=[C:10]([Br:12])[S:9][C:8]=1[C:13]([O:15][CH2:16][CH3:17])=[O:14].[N+:18]([O-])([OH:20])=[O:19]>>[Br:6][C:7]1[C:11]([N+:18]([O-:20])=[O:19])=[C:10]([Br:12])[S:9][C:8]=1[C:13]([O:15][CH2:16][CH3:17])=[O:14]Komponenten
4
Reaktionsbedingungen
- Temperatur
- -5 °C
Versuchsvorschrift
Sulfuric acid (27.6 g, 15.0 ml, 281.0 mmol) was added in a dropwise manner to ethyl 3,5-dibromothiophene-2-carboxylate (Prepared according to procedure reported in JCS Perkin Trans-1: Organic and Bioorganic Chemistry (1972-1999), 1973, p 1766-1770), 5.0 g (15.92 mmol), at room temperature (about 25° C.). The reaction mixture was then cooled to −5° C. and to the cooled mixture was added nitric acid (2.0 g, 2.04 ml, 31.84 mmol) slowly. The reaction mixture was then stirred at 0° C. for 1 hr. The progress of the reaction was monitored by TLC. The reaction mixture was then poured onto ice-water (150 ml). The mixture so obtained was extracted with ethyl acetate (2×100 ml). The combined organic layer was dried over sodium sulphate and was concentrated under reduced pressure to obtain a crude product, which was then purified by column chromatography over silica gel (100-200 mesh) using 2% ethyl acetate in hexanes as an eluent to obtain the title compound (3.40 g, 59.54%).