Acetyl chloride → Methyl benzo[b]thiophene-7-carboxylate
Reaction equation
[C:1](Cl)(=O)C.[S:5]1[CH:9]=[CH:8][C:7]2[CH:10]=[CH:11][CH:12]=[C:13]([C:14]([OH:16])=[O:15])[C:6]1=2>CO>[CH3:1][O:15][C:14]([C:13]1[C:6]2[S:5][CH:9]=[CH:8][C:7]=2[CH:10]=[CH:11][CH:12]=1)=[O:16]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Acetyl chloride (14.8 mmol; 1.05 mL) is added to a solution of benzo[b]thiophene-7-carboxylic acid (4.94 mmol; 880 mg) in methanol (20 mL). The reaction mixture is stirred at reflux for 24 h. The solvent is removed under reduced pressure. The residue is taken up in ethyl acetate washed with water, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to yield the title compound (880 mg, 92%) as colorless oil. 1H NMR (CDCl3): δ 8.12 (dd, 1H, J=7.2 Hz, 0.6 Hz), 8.03 (dd, 1H, J=7.6 Hz, 1.2 Hz), 7.58 (d, 1H, J=5.6 Hz), 7.46 (t, 1H, J=7.6 Hz), 7.41 (t, 1H, J=5.2 Hz), 4.03 (s, 3H).