diethyl 2,2-dimethylpropanedioate

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of-sodium methoxide (0.343 g, 14.9 mmol), benzylurea (1.6 g, 10.6 mmol), diethyl dimethylmalonate (1.9 g, 10 mmol) and methanol (15 mL) was heated 6 hours at reflux. The reaction mixture was concentrated and the residue was stirred with water (30 mL) at 5° C. and then hydrochloric acid was added. The solids were collected, washed with water and dried to give 1-benzyl-5,5-dimethyl-2,4,6(1H,3H,5H)-pyrimidinetrione, m.p 136°-137° C. was heated 6 hours at reflux The reaction mixture was concentrated hydrochloric acid was added The solids were collected washed with water dried

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 25 g 2,2-Dimethyl-malonic acid diethyl ester, 7.8 g potassium hydroxide and 500 ml ethanol were mixed in a round-bottomed flask and refluxed for 3 hours. Then again 2.2 g potassium hydroxide were added and the mixture was refluxed overnight. The solvent was removed on a rotovap, 250 ml H2O were added and the mixture was washed with ether. The aqueous phase was acidified with HCl to pH 3-4 followed by two extractions with dichloromethane. The organic solvent was dried and evaporated and the resulting product was characterized by 1H-NMR. refluxed for 3 hours the mixture was refluxed overnight The solvent was removed on a rotovap, 250 ml H2O were added the mixture was washed with ether followed by two extractions with dichloromethane The organic solvent was dried evaporated

反応条件: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of-sodium methoxide (0.343 g, 14.9 mmol), benzylurea (1.6 g, 10.6 mmol), diethyl dimethylmalonate (1.9 g, 10 mmol) and methanol (15 mL) was heated 6 hours at reflux. The reaction mixture was concentrated and the residue was stirred with water (30 mL) at 5° C. and then hydrochloric acid was added. The solids were collected, washed with water and dried to give 1-benzyl-5,5-dimethyl-2,4,6(1H,3H,5H)-pyrimidinetrione, m.p 136°-137° C. was heated 6 hours at reflux The reaction mixture was concentrated hydrochloric acid was added The solids were collected washed with water dried

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 0.023 ml of concentrated sulfuric acid are cautiously added to a solution of 4 g of 2,2-dimethylmalonic acid in 30 ml of a 1:2 absolute ethanol/toluene mixture. The reaction mixture is refluxed, distilling the azeotropic water/toluene mixture and adding every few an ethanol/toluene mixture. After 3 hours, the reaction mixture is added with 50 ml of water and extracted with ethyl acetate (3×15 ml). The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure. The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt). 3.3 g of 2,2-dimethylmalonic acid diethyl ester are obtained. The reaction mixture is refluxed distilling the azeotropic water/toluene mixture adding every few an ethanol/toluene mixture the reaction mixture is added with 50 ml of water extracted with ethyl acetate (3×15 ml) The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt)

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 0.023 ml of concentrated sulfuric acid are cautiously added to a solution of 4 g of 2,2-dimethylmalonic acid in 30 ml of a 1:2 absolute ethanol/toluene mixture. The reaction mixture is refluxed, distilling the azeotropic water/toluene mixture and adding every few an ethanol/toluene mixture. After 3 hours, the reaction mixture is added with 50 ml of water and extracted with ethyl acetate (3×15 ml). The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure. The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt). 3.3 g of 2,2-dimethylmalonic acid diethyl ester are obtained. The reaction mixture is refluxed distilling the azeotropic water/toluene mixture adding every few an ethanol/toluene mixture the reaction mixture is added with 50 ml of water extracted with ethyl acetate (3×15 ml) The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt)

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 0.023 ml of concentrated sulfuric acid are cautiously added to a solution of 4 g of 2,2-dimethylmalonic acid in 30 ml of a 1:2 absolute ethanol/toluene mixture. The reaction mixture is refluxed, distilling the azeotropic water/toluene mixture and adding every few an ethanol/toluene mixture. After 3 hours, the reaction mixture is added with 50 ml of water and extracted with ethyl acetate (3×15 ml). The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure. The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt). 3.3 g of 2,2-dimethylmalonic acid diethyl ester are obtained. The reaction mixture is refluxed distilling the azeotropic water/toluene mixture adding every few an ethanol/toluene mixture the reaction mixture is added with 50 ml of water extracted with ethyl acetate (3×15 ml) The combined organic extracts are dried over sodium sulfate and solvent is evaporated off under reduced pressure The residue is purified by silica gel chromatography (eluent 2:1 hexane/AcOEt)

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: N-(3,5-Difluoro-benzyl)-2,2-dimethyl-malonamic acid was prepared in analogy to N-(3,5-difluoro-benzyl)-2-methyl-malonamic acid (example 1) from diethyl 2,2-dimethyl-malonate.

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: N-(3,5-Difluoro-benzyl)-2,2-dimethyl-malonamic acid was prepared in analogy to N-(3,5-difluoro-benzyl)-2-methyl-malonamic acid (example 1) from diethyl 2,2-dimethyl-malonate.