2-methylidenepentanedioic acid

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

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chloride (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for 1 hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for 1 hour The reaction mixture is concentrated to dryness

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chlorine (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for one hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for one hour The reaction mixture is concentrated to dryness

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chlorine (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for one hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for one hour The reaction mixture is concentrated to dryness

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cooled solution (5° C.) of thiobenzoic acid (5.5 g, 39.8 mmol) in acetone (75 mL), was added 2-methyleneglutaric acid (5.25 g, 36.4 mmol) with stirring. To the resulting solution, 4-dimethylaminopyridine (0.5 g, 4.1 mmol) was added and the solution was stirred for 5 hours at 5° C. The temperature was slowly raised to 60° C. and refluxed for 20 hours. The resulting solution was treated with activated charcoal (1 g) and filtered. The clear solution was evaporated to a thick liquid and cold distilled water (100 ml) was added with rapid stirring. The white precipitate formed was filtered and suspended in a saturated aqueous solution of NaHCO3. After stirring for 15 minutes, the suspension was filtered and the clear filtrate extracted with three portions of EtOAc. The aqueous fraction was then acidified with 18% HCl. The white precipitate formed was collected by filtration, washed with cold distilled water, and dried at 50° C. The crude product was crystallized from aqueous ethanol to yield white shiny crystals, representing a yield of 7.71 g (75%) of the captioned product (mp 144° C.). the solution was stirred for 5 hours at 5° C refluxed for 20 hours filtered The clear solution was evaporated to a thick liquid cold distilled water (100 ml) was added with rapid stirring The white precipitate formed was filtered After stirring for 15 minutes the suspension was filtered the clear filtrate extracted with three portions of EtOAc The white precipitate formed was collected by filtration washed with cold distilled water dried at 50° C The crude product was crystallized from aqueous ethanol to yield white shiny crystals

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cooled solution (5° C.) of thiobenzoic acid (5.5 g, 39.8 mmol) in acetone (75 mL), was added 2-methyleneglutaric acid (5.25 g, 36.4 mmol) with stirring. To the resulting solution, 4-dimethylaminopyridine (0.5 g, 4.1 mmol) was added and the solution was stirred for 5 hours at 5° C. The temperature was slowly raised to 60° C. and refluxed for 20 hours. The resulting solution was treated with activated charcoal (1 g) and filtered. The clear solution was evaporated to a thick liquid and cold distilled water (100 ml) was added with rapid stirring. The white precipitate formed was filtered and suspended in a saturated aqueous solution of NaHCO3. After stirring for 15 minutes, the suspension was filtered and the clear filtrate extracted with three portions of EtOAc. The aqueous fraction was then acidified with 18% HCl. The white precipitate formed was collected by filtration, washed with cold distilled water, and dried at 50° C. The crude product was crystallized from aqueous ethanol to yield white shiny crystals, representing a yield of 7.71 g (75%) of the captioned product (mp 144° C.). the solution was stirred for 5 hours at 5° C refluxed for 20 hours filtered The clear solution was evaporated to a thick liquid cold distilled water (100 ml) was added with rapid stirring The white precipitate formed was filtered After stirring for 15 minutes the suspension was filtered the clear filtrate extracted with three portions of EtOAc The white precipitate formed was collected by filtration washed with cold distilled water dried at 50° C The crude product was crystallized from aqueous ethanol to yield white shiny crystals

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

Procedure: 20.9 g of 2-methyleneglutaric acid are dissolved at 50°, with stirring, in 150 ml of 75% H2SO4, and 24.2 g of 2-mercaptobenzthiazole are added slowly. The reaction is exothermic and the temperature rises to 60°. The reaction mixture is then stirred for 2 hours at 55°. The resulting brown solution is poured into 500 ml of water and stirred for 1 hour. 600 ml of water are then added, and the white precipitate is filtered off. Recrystallisation from aqueous methanol gives 4-(benzthiazol-2-ylthio)-butane-1,3-dicarboxylic acid, melting at 152°-154°. rises to 60° stirred for 1 hour the white precipitate is filtered off Recrystallisation from aqueous methanol

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chloride (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for 1 hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for 1 hour The reaction mixture is concentrated to dryness

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chloride (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for 1 hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for 1 hour The reaction mixture is concentrated to dryness

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chlorine (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for one hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for one hour The reaction mixture is concentrated to dryness

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

Procedure: A mixture of 2-methyleneglutaric acid [Ber. 34, 427 (1901)] (40 g.) and acetyl chloride (80 ml.) is heated on the steam bath for 1.5 hours. The excess acetyl chloride is removed in vacuo (75°) and the residue is evaporated from toluene twice. Finally, the residue is dissolved in ethanol and heated on the steam bath for one hour. The reaction mixture is concentrated to dryness to yield 2-methylene-4-(ethoxycarbonyl)butyric acid. is heated on the steam bath for 1.5 hours The excess acetyl chloride is removed in vacuo (75°) the residue is evaporated from toluene twice Finally, the residue is dissolved in ethanol heated on the steam bath for one hour The reaction mixture is concentrated to dryness

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