Iodine → HCID 57517766, compound

Participants

Reaction Conditions

Reaction Steps

Magnesium turnings (6.8 g, 0.27 mmol) are introduced into diethyl ether (30 ml), and, while stirring, a solution of 2-bromo-3-methyl-thiophene (50 g, 0.282 mol) in diethyl ether (100 ml) is added dropwise. The reaction can be initiated if necessary by adding iodine crystals. During the addition, the reaction mixture should boil gently. After the addition, the mixture was stirred at room temperature for 1 hour. A suspension of 5-chloroisatin (19 g, 0.105 mol) in THF (200 ml) was added to the Grignard solution while cooling slightly (temperature 18-24° C.) and the mixture was stirred at room temperature for 30 min. The reaction mixture was stirred into ammonium chloride solution and extracted several times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over magnesium sulfate and concentrated under reduced pressure. The residue was stirred with diethyl ether. The resulting precipitate was filtered off, washed with diethyl ether and dried. 26 g of the desired intermediate were obtained.

Provenance & Evidence