ethyl 4-chloro-2-methoxyimino-3-oxobutanoate

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: Ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (50 g.) was added over 3 minutes with stirring at ambient temperature to a solution of thiourea (18.4 g.) and sodium acetate (19.8 g.) in a mixture of methanol (250 ml.) and water (250 ml.). After stirring for 35 minutes at 40° to 45° C., the reaction mixture was cooled with ice and adjusted to pH 6.3 with a saturated aqueous solution of sodium bicarbonate. After stirring for 30 minutes at the same temperature, precipitates were collected by filtration, washed with water (200 ml.) and then with diisopropyl ether (100 ml.), and dried to give colorless crystals of ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (37.8 g.), m.p. 161° to 162° C. the reaction mixture was cooled with ice After stirring for 30 minutes at the same temperature precipitates were collected by filtration washed with water (200 ml.) with diisopropyl ether (100 ml.), and dried

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

Procedure: Sulfuryl chloride (235 ml.) was dropwise added over 20 minutes with stirring and ice-cooling to a solution of ethyl 2-methoxyiminoacetoacetate (syn isomer) (500 g.) in acetic acid (500 ml.), and the mixture was stirred overnight under cooling with water. Nitrogen gas was introduced to the reaction mixture for 2 hours, and the resulting mixture was poured into water (2.5 l.) After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.), the extracts were combined. The combined extract were washed with a saturated aqueous solution of sodium chloride, and adjusted to pH 6.5 by adding water (800 ml.) and sodium bicarbonate. Methylene chloride layer was separated, washed with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off to give ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (559 g.). the mixture was stirred overnight Nitrogen gas was introduced to the reaction mixture for 2 hours After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.) The combined extract were washed with a saturated aqueous solution of sodium chloride by adding water (800 ml.) and sodium bicarbonate Methylene chloride layer was separated washed with an aqueous solution of sodium chloride dried over magnesium sulfate The solvent was distilled off

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

Procedure: Sulfuryl chloride (235 ml.) was dropwise added over 20 minutes with stirring and ice-cooling to a solution of ethyl 2-methoxyiminoacetoacetate (syn isomer) (500 g.) in acetic acid (500 ml.), and the mixture was stirred overnight under cooling with water. Nitrogen gas was introduced to the reaction mixture for 2 hours, and the resulting mixture was poured into water (2.5 l). After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.), the extracts were combined. The combined extracts were washed with a saturated aqueous solution of sodium chloride, and adjusted to pH 6.5 by adding water (800 ml.) and sodium bicarbonate. Methylene chloride layer was separated, washed with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off to give ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (559 g.). the mixture was stirred overnight Nitrogen gas was introduced to the reaction mixture for 2 hours After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.) The combined extracts were washed with a saturated aqueous solution of sodium chloride by adding water (800 ml.) and sodium bicarbonate Methylene chloride layer was separated washed with an aqueous solution of sodium chloride dried over magnesium sulfate The solvent was distilled off

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

Procedure: Sulfuryl chloride (235 ml.) was dropwise added over 20 minutes with stirring and ice-cooling to a solution of ethyl 2-methoxyiminoacetoacetate (syn isomer) (500 g.) in acetic acid (500 ml.), and the mixture was stirred overnight under cooling with water. Nitrogen gas was introduced to the reaction mixture for 2 hours, and the resulting mixture was poured into water (2.5 l). After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.), the extracts were combined. The combined extracts were washed with a saturated aqueous solution of sodium chloride, and adjusted to pH 6.5 by adding water (800 ml.) and sodium bicarbonate. Methylene chloride layer was separated, washed with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off to give ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (559 g.). the mixture was stirred overnight Nitrogen gas was introduced to the reaction mixture for 2 hours After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.) The combined extracts were washed with a saturated aqueous solution of sodium chloride by adding water (800 ml.) and sodium bicarbonate Methylene chloride layer was separated washed with an aqueous solution of sodium chloride dried over magnesium sulfate The solvent was distilled off

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

Procedure: Ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (50 g.) was added over 3 minutes with stirring at ambient temperature to a solution of thiourea (18.4 g.) and sodium acetate (19.8 g.) in a mixture of methanol (250 ml.) and water (250 ml.). After stirring for 35 minutes at 40° to 45° C., the reaction mixture was cooled with ice and adjusted to pH 6.3 with a saturated aqueous solution of sodium bicarbonate. After stirring for 30 minutes at the same temperature, precipitates were collected by filtration, washed with water (200 ml.) and then with diisopropyl ether (100 ml.), and dried to give colorless crystals of ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (37.8 g.), mp 161° to 162° C. the reaction mixture was cooled with ice After stirring for 30 minutes at the same temperature precipitates were collected by filtration washed with water (200 ml.) with diisopropyl ether (100 ml.), and dried

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

Procedure: Ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (50 g.) was added over 3 minutes with stirring at ambient temperature to a solution of thiourea (18.4 g.) and sodium acetate (19.8 g.) in a mixture of methanol (250 ml.) and water (250 ml.). After stirring for 35 minutes at 40° to 45° C., the reaction mixture was cooled with ice and adjusted to pH 6.3 with a saturated aqueous solution of sodium bicarbonate. After stirring for 30 minutes at the same temperature, precipitates were collected by filtration, washed with water (200 ml.) and then with diisopropyl ether (100 ml.), and dried to give colorless crystals of ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (37.8 g.), mp 161° to 162° C. the reaction mixture was cooled with ice After stirring for 30 minutes at the same temperature precipitates were collected by filtration washed with water (200 ml.) with diisopropyl ether (100 ml.), and dried

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

Procedure: Sulfuryl chloride (235 ml.) was dropwise added over 20 minutes with stirring and ice-cooling to a solution of ethyl 2-methoxyiminoacetoacetate (syn isomer) (500 g.) in acetic acid (500 ml.), and the mixture was stirred overnight under cooling with water. Nitrogen gas was introduced to the reaction mixture for 2 hours, and the resulting mixture was poured into water (2.5 l). After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.), the extracts were combined. The combined extracts were washed with a saturated aqueous solution of sodium chloride, and adjusted to pH 6.5 by adding water (800 ml.) and sodium bicarbonate. Methylene chloride layer was separated, washed with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off to give ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (559 g.). the mixture was stirred overnight Nitrogen gas was introduced to the reaction mixture for 2 hours After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.) The combined extracts were washed with a saturated aqueous solution of sodium chloride by adding water (800 ml.) and sodium bicarbonate Methylene chloride layer was separated washed with an aqueous solution of sodium chloride dried over magnesium sulfate The solvent was distilled off

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

Procedure: Ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (50 g.) was added over 3 minutes with stirred at ambient temperature to a solution of thiourea (18.4 g.) and sodium acetate (19.8 g.) in a mixture of methanol (250 ml.) and water (250 ml.). After stirring for 35 minutes at 40° to 45° C., the reaction mixture was cooled with ice and adjusted to pH 6.3 with a saturated aqueous solution of sodium bicarbonate. After stirring for 30 minutes at the same temperature, precipitates were collected by filtration, washed with water (200 ml.) and then with diisopropyl ether (100 ml.), and dried to give colorless crystals of ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (37.8 g.), m.p. 161° to 162° C. the reaction mixture was cooled with ice After stirring for 30 minutes at the same temperature precipitates were collected by filtration washed with water (200 ml.) with diisopropyl ether (100 ml.), and dried

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

Procedure: Sulfuryl chloride (235 ml.) was dropwise added over 20 minutes with stirring and ice-cooling to a solution of ethyl 2-methoxyiminoacetoacetate (syn isomer) (500 g.) in acetic acid (500 ml.), and the mixture was stirred overnight under cooling with water. Nitrogen gas was introduced to the reaction mixture for 2 hours, and the resulting mixture was poured into water (2.5 l.) After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.), the extracts were combined. The combined extract were washed with a saturated aqueous solution of sodium chloride, and adjusted to pH 6.5 by adding water (800 ml.) and sodium bicarbonate. Methylene chloride layer was separated, washed with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off to give ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (559 g.). the mixture was stirred overnight Nitrogen gas was introduced to the reaction mixture for 2 hours After extracting with methylene chloride (500 ml.) and twice with methylene chloride (200 ml.) The combined extract were washed with a saturated aqueous solution of sodium chloride by adding water (800 ml.) and sodium bicarbonate Methylene chloride layer was separated washed with an aqueous solution of sodium chloride dried over magnesium sulfate The solvent was distilled off

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

Procedure: Ethyl 2-methoxyimino-4-chloroacetoacetate (syn isomer) (50 g.) was added over 3 minutes with stirring at ambient temperature to a solution of thiourea (18.4 g.) and sodium acetate (19.8 g.) in a mixture of methanol (250 ml.) and water (250 ml.). After stirring for 35 minutes at 40° to 45° C., the reaction mixture was cooled with ice and adjusted to pH 6.3 with a saturated aqueous solution of sodium bicarbonate. After stirring for 30 minutes at the same temperature, precipitates were collected by filtration, washed with water (200 ml.) and then with diisopropyl ether (100 ml.), and dried to give colorless crystals of ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (37.8 g.), mp 161° to 162° C. the reaction mixture was cooled with ice After stirring for 30 minutes at the same temperature precipitates were collected by filtration washed with water (200 ml.) with diisopropyl ether (100 ml.), and dried