C(Cl)(Cl)Cl.C(O)(=O)C.[S:9]1[CH:13]=[CH:12][C:11]([CH2:14][C:15]([O:17][CH2:18][CH3:19])=[O:16])=[CH:10]1.C1C(=O)N([Br:27])C(=O)C1>O>[Br:27][C:10]1[S:9][CH:13]=[CH:12][C:11]=1[CH2:14][C:15]([O:17][CH2:18][CH3:19])=[O:16]In a 250 ml 3-neck flask containing 50 ml of CHCl3 and 50 ml of glacial acetic acid, 9.5 grams (0.0558 mol) of ethyl thiophene-3-acetate was added, followed by 9.93 grams (0.0558 mol) of NBS. The mixture was stirred at room temperature for 12 hours. The mixture became clear yellow solution after 1 hour and then was cooled down to room temperature, and poured into 200 ml deionized (DI) water. The organic portion was washed again with 100 ml of DI-water, and then finally washed with 100 ml of 5% aqueous sodium bicarbonate solution. After having been dried over magnesium sulfate, the solvent was filtered and the product was concentrated under vacuum. The resulting residue was vacuum distilled at 95° C. under 1 mm mercury (Hg) yielding 12.3 grams of ethyl 2-bromothiophene-3-acetate (88% yield). 1H NMR (CDCl3): 1.26 (t, 3H), 3.60 (s, 2H), 4.16 (q, 2H), 6.93 (d, 1H), 7.22 (d, 1H).
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