7-methoxy-1-benzothiophene-2-carboxylic acid methyl ester

7-methoxy-1-benzothiophene-2-carboxylic acid methyl ester

To a solution of 600 mg (3.31 mmol) of 3-methoxy-2-nitrobenzaldehyde in 8 ml of DMF 550 mg (3.97 mmol) of potassium carbonate and 350 mg (3.31 mmol)

Mercaptoacetate added. The reaction mixture is heated for 4 h at 70 ° C. After cooling water is added. The resulting precipitate is filtered, washed with water and dried in vacuo. Obtained 387 mg (45.7% of theory) of the title compound. 

1H NMR (200 MHz, DMSO-d _6): δ = 8.21 (s, IH), 7.63 (d, IH), 7.46 (dd, IH), 7.11 (d, IH), 

3.98 (s, 3H), 

3.89 (s, 3H) ppm. 

MS (ESIpos): m / z = 240 (M + NH ₄₎ ⁺
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