ethyl 3-amino-5-chloro-1-benzofuran-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3-amino-5-chloro-benzofuran-2-carboxylic acid ethyl ester (2.8 g, 11.7 mmol) in benzene (35 mL) was added ethyl chloroformate (1.3 mL, 14.0 mmol) followed by K2CO3 (4.5 g, 35.1 mmol). After heating at reflux for 14 h, the mixture was filtered, washing with benzene. The filtrate was concentrated to afford the desired product (100%), which was used in the next step without further purification. 1H NMR (CDCl3): 8.69 (s, 1H), 8.45 (s, 1H), 7.47-7.39 (m, 2H), 4.48 (q, J=7.1 Hz, 2H), 4.30 (q, J=7.1 Hz, 2H), 1.55 (t, J=7.1 Hz, 3H), 1.35 (t, J=7.1 Hz, 3H). After heating at reflux for 14 h the mixture was filtered washing with benzene The filtrate was concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of (4-chloro-2-cyano-phenoxy)-acetic acid ethyl ester (15.3 g, 64.0 mmol) in DMF (150 mL) was added K2CO3 (14.1 g, 102 mmol). After heating at reflux for 10 h, the reaction mixture was poured into ice water. The crude product was collected by filtration as a brown solid (14.37 g, 92%). 1H NMR (CDCl3): 7.54 (s, 1H), 7.41-7.27 (m, 2H), 4.94 (s, 2H), 4.44 (q, J=7.1 Hz, 2H), 1.44 (t, J=7.1 Hz, 3H). After heating at reflux for 10 h The crude product was collected by filtration as a brown solid (14.37 g, 92%)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3-amino-5-chloro-benzofuran-2-carboxylic acid ethyl ester (2.8 g, 11.7 mmol) in benzene (35 mL) was added ethyl chloroformate (1.3 mL, 14.0 mmol) followed by K2CO3 (4.5 g, 35.1 mmol). After heating at reflux for 14 h, the mixture was filtered, washing with benzene. The filtrate was concentrated to afford the desired product (100%), which was used in the next step without further purification. 1H NMR (CDCl3): 8.69 (s, 1H), 8.45 (s, 1H), 7.47-7.39 (m, 2H), 4.48 (q, J=7.1 Hz, 2H), 4.30 (q, J=7.1 Hz, 2H), 1.55 (t, J=7.1 Hz, 3H), 1.35 (t, J=7.1 Hz, 3H). After heating at reflux for 14 h the mixture was filtered washing with benzene The filtrate was concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of (4-chloro-2-cyano-phenoxy)-acetic acid ethyl ester (15.3 g, 64.0 mmol) in DMF (150 mL) was added K2CO3 (14.1 g, 102 mmol). After heating at reflux for 10 h, the reaction mixture was poured into ice water. The crude product was collected by filtration as a brown solid (14.37 g, 92%). 1H NMR (CDCl3): 7.54 (s, 1H), 7.41-7.27 (m, 2H), 4.94 (s, 2H), 4.44 (q, J=7.1 Hz, 2H), 1.44 (t, J=7.1 Hz, 3H). After heating at reflux for 10 h The crude product was collected by filtration as a brown solid (14.37 g, 92%)

Conditions: temp:0.00; pressure:0.00; stir: