2-Bromothiophene → Ethyl (5-bromothiophen-2-yl)(oxo)acetate

Participants

Reaction Steps

To a solution of 2-bromothiophene (10 mL, 103.3 mmol, 1.0 eq) in dichloromethane (200 mL) was added ethyl 2-chloro-2-oxoacetate (13.8 mL, 123.9 mmol, 1.2 eq) and aluminum trichloride (16.5 g, 123.9 mmol, 1.2 eq) at 0° C. After stirring for 10 minutes, the reaction mixture was diluted with dichloromethane and poured into ice. The combined organic phase was washed (brine), dried (MgSO4), filtered and concentrated to give a residue, the residue was purified by silica gel column chromatography to yield ethyl 2-(5-bromothiophen-2-yl)-2-oxoacetate (7.0 g, 25.8%). LC-MS (m/z): 262.8 [M+H]+. 1H NMR (400 MHz, DMSO-d6): δ 1.33 (t, J=7.2 Hz, 3H), 4.33-4.39 (m, 2H), 7.48 (d, J=3.6 Hz, 1H), 7.94 (d, J=4.4 Hz, 1H).

Provenance & Evidence