ethyl 4-amino-5-cyano-2-hydroxybenzoate

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 stirred solution of 4.1 parts of ethyl 4-amino-5-cyano-2-hydroxybenzoate in 40 parts of 2-propanone were added successively 2.52 parts of dimethyl sulfate and 4.1 parts of potassium carbonate. The whole was stirred and refluxed for 3 hours. The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone. The filtrate was evaporated and the solid residue was crystallized from 24 parts of 2-propanol, yielding 3.5 parts (79.5%) of ethyl 4-amino-5-cyano-2-methoxybenzoate; mp. 164.5° C. (intermediate 110). refluxed for 3 hours The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone The filtrate was evaporated the solid residue was crystallized from 24 parts of 2-propanol

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 4-amino-5-cyano-2-hydroxybenzoate (3 g, 14.55 mmol) is treated with 60 ml of a 10% strength sodium hydroxide solution and the mixture is stirred at 50° C. for one hour. After cooling, the reaction solution is acidified with concentrated hydrochloric acid, diluted with water and the precipitate is filtered off with suction. The desired product is obtained after recrystallization from ethanol in 62% yield (1.6 g). After cooling the precipitate is filtered off with suction

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 4-amino-5-cyano-2-hydroxybenzoate (3 g, 14.55 mmol) is treated with 60 ml of a 10% strength sodium hydroxide solution and the mixture is stirred at 50° C. for one hour. After cooling, the reaction solution is acidified with concentrated hydrochloric acid, diluted with water and the precipitate is filtered off with suction. The desired product is obtained after recrystallization from ethanol in 62% yield (1.6 g). After cooling the precipitate is filtered off with suction

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

Procedure: According to H.-W-. Schmidt et al. (Liebigs Ann. Chem. 1979, 2005-10), ethyl acetate (42 g, 323 mmol) is added to a solution of sodium (15 g, 23 mmol) in ethanol (4.0 l) and the mixture is stirred at room temperature for 30 minutes. Ethoxymethylene-malononitrile (40.6 g, 332 mmol) is added. After 30 minutes at 80° C., the reaction mixture is allowed to cool to room temperature and the resulting precipitate is filtered off with suction. The precipitate is dissolved using water, and the aqueous phase is acidified with concentrated hydrochloric acid and the resulting precipitate is filtered off with suction again. After recrystallization from acetic acid, the crystals are filtered off with suction, washed with water and subsequently dried. The desired product is obtained in 29% yield (21.5 g). After 30 minutes at 80° C. to cool to room temperature the resulting precipitate is filtered off with suction The precipitate is dissolved the resulting precipitate is filtered off with suction again After recrystallization from acetic acid the crystals are filtered off with suction washed with water subsequently dried

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

Procedure: According to H.-W-. Schmidt et al. (Liebigs Ann. Chem. 1979, 2005-10), ethyl acetate (42 g, 323 mmol) is added to a solution of sodium (15 g, 23 mmol) in ethanol (4.0 l) and the mixture is stirred at room temperature for 30 minutes. Ethoxymethylene-malononitrile (40.6 g, 332 mmol) is added. After 30 minutes at 80° C., the reaction mixture is allowed to cool to room temperature and the resulting precipitate is filtered off with suction. The precipitate is dissolved using water, and the aqueous phase is acidified with concentrated hydrochloric acid and the resulting precipitate is filtered off with suction again. After recrystallization from acetic acid, the crystals are filtered off with suction, washed with water and subsequently dried. The desired product is obtained in 29% yield (21.5 g). After 30 minutes at 80° C. to cool to room temperature the resulting precipitate is filtered off with suction The precipitate is dissolved the resulting precipitate is filtered off with suction again After recrystallization from acetic acid the crystals are filtered off with suction washed with water subsequently dried

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

Procedure: To a stirred solution of 4.1 parts of ethyl 4-amino-5-cyano-2-hydroxybenzoate in 40 parts of 2-propanone were added successively 2.52 parts of dimethyl sulfate and 4.1 parts of potassium carbonate. The whole was stirred and refluxed for 3 hours. The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone. The filtrate was evaporated and the solid residue was crystallized from 24 parts of 2-propanol, yielding 3.5 parts (79.5%) of ethyl 4-amino-5-cyano-2-methoxybenzoate; mp. 164.5° C. (intermediate 110). refluxed for 3 hours The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone The filtrate was evaporated the solid residue was crystallized from 24 parts of 2-propanol

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

Procedure: To a stirred solution of 4.1 parts of ethyl 4-amino-5-cyano-2-hydroxybenzoate in 40 parts of 2-propanone were added successively 2.52 parts of dimethyl sulfate and 4.1 parts of potassium carbonate. The whole was stirred and refluxed for 3 hours. The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone. The filtrate was evaporated and the solid residue was crystallized from 24 parts of 2-propanol, yielding 3.5 parts (79.5%) of ethyl 4-amino-5-cyano-2-methoxybenzoate; mp. 164.5° C. (intermediate 110). refluxed for 3 hours The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone The filtrate was evaporated the solid residue was crystallized from 24 parts of 2-propanol

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

Procedure: To a stirred solution of 4.1 parts of ethyl 4-amino-5-cyano-2-hydroxybenzoate in 40 parts of 2-propanone were added successively 2.52 parts of dimethyl sulfate and 4.1 parts of potassium carbonate. The whole was stirred and refluxed for 3 hours. The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone. The filtrate was evaporated and the solid residue was crystallized from 24 parts of 2-propanol, yielding 3.5 parts (79.5%) of ethyl 4-amino-5-cyano-2-methoxybenzoate; mp. 164.5° C. (intermediate 110). refluxed for 3 hours The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone The filtrate was evaporated the solid residue was crystallized from 24 parts of 2-propanol

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

Procedure: To a stirred solution of 4.1 parts of ethyl 4-amino-5-cyano-2-hydroxybenzoate in 40 parts of 2-propanone were added successively 2.52 parts of dimethyl sulfate and 4.1 parts of potassium carbonate. The whole was stirred and refluxed for 3 hours. The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone. The filtrate was evaporated and the solid residue was crystallized from 24 parts of 2-propanol, yielding 3.5 parts (79.5%) of ethyl 4-amino-5-cyano-2-methoxybenzoate; mp. 164.5° C. (intermediate 110). refluxed for 3 hours The reaction mixture was filtered while hot and the filter-cake was washed with 2-propanone The filtrate was evaporated the solid residue was crystallized from 24 parts of 2-propanol

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Ethyl 4-amino-5-cyano-2-hydroxybenzoate (3 g, 14.55 mmol) is treated with 60 ml of a 10% strength sodium hydroxide solution and the mixture is stirred at 50° C. for one hour. After cooling, the reaction solution is acidified with concentrated hydrochloric acid, diluted with water and the precipitate is filtered off with suction. The desired product is obtained after recrystallization from ethanol in 62% yield (1.6 g). After cooling the precipitate is filtered off with suction