1860-99-7

Journal of Heterocyclic Chemistry, 13, p. 1099, 1976 DOI: 10.1002/jhet.5570130534

The general procedure for the synthesis of 2-bromothiophene-3-carboxaldehyde from 2-bromo-3-bromomethylthiophene is as follows: in a 250-mL two-necked flask, 11.9 g (46 mmol) of undried 2-bromo-3-(bromomethyl)thiophene (molecular weight 256 g/mol) was added. Under nitrogen protection, 20.8 g (74 mmol, 1.6 eq.) of IBX (molecular weight 280 g/mol) and 130 mL of anhydrous DMSO were added to the reaction system.The reaction mixture was heated in an oil bath at 60-70 °C for 3-4 h. The reaction was completed by the addition of 20.8 g (74 mmol, 1.6 eq.) of IBX (molecular weight 280 g/mol) and 130 mL of anhydrous DMSO. Upon completion of the reaction, 20 mL of deionized water was added to quench the reaction. The reaction mixture was extracted with dichloromethane and the precipitate was washed with plenty of dichloromethane to give a white solid. The filtrate was collected by filtration, subsequently dried and purified by column chromatography with the eluent being petroleum ether/ethyl acetate (40:1, V/V).

[1] Journal of the American Chemical Society, 2014, vol. 136, # 19, p. 7132 - 7139
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[3] Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999), 1983, p. 813 - 820