Hydrochloric Acid → Diethyl alpha-(4-methoxyphenacyl)malonate

2.43 g (4.7 mmol) of diethyl α-(3-cyclopentyloxy-4-methoxybenzyl)-α-(4-methoxyphenacyl)malonate [prepared as described in step (ii) above] and 1.26 g (4.7 mmol) of 18-crown-6 were dissolved in 50 ml of benzene, and 4.70 ml (4.7 mmol) of a 1.1M solution of potassium hydroxide in ethanol were added to the resulting solution. The mixture was then stirred for 30 minutes, after which the ethanol in the reaction mixture was removed by distillation under reduced pressure. The remaining reaction solution was heated under reflux for 14 hours and then the reaction mixture was cooled to room temperature. The mixture was then acidified by the addition of 3N aqueous hydrochloric acid, and the resulting mixture was extracted with ethyl acetate. The organic extract was washed with water and dried over anhydrous magnesium sulfate, and then the solvent was removed by distillation under reduced pressure. The residue thus obtained was applied to a silica gel chromatography column and eluted with a 1:4 by volume mixture of ethyl acetate and hexane, to give 1.68 g of the title compound as slightly yellow crystals (yield 81%).

1. customafter which the ethanol in the reaction mixture was removed by distillation under reduced pressure
2. customThe remaining reaction solution
3. temperaturewas heated
4. temperatureunder reflux for 14 hours
5. extractionthe resulting mixture was extracted with ethyl acetate
6. extractionThe organic extract
7. washwas washed with water
8. dry with materialdried over anhydrous magnesium sulfate
9. customthe solvent was removed by distillation under reduced pressure
10. customThe residue thus obtained
11. washeluted with a 1:4 by volume mixture of ethyl acetate and hexane

ORD record

ord-04ae5fc0e89c48eeb09bd5517fa4cc56

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

USRE039420E1