Piperidine → HCID 53921037, compound

A 8.1 g (44.5 mmol) of syringaldehyde, 7.2 g (44.4 mmol) of ethyl a-dimethylcarbamoylacetate and 6.6 ml (66.7 mmol) of piperidine in 150 ml of ethanol solution was stirred at 110° C. for about 12 hours. The mixture was concentrated under reduced pressure and purified by silica gel column chromatography (methanol/chloroform=2-4%). An oily product thus obtained was dissolved in 50 ml of tetrahydrofuran. To the solution was added an aqueous potassium hydroxide solution (4.3 g/10 ml), and the solution was stirred at room temperature for 15 hours. A 50 ml of ethyl acetate was added to the solution. The mixture was extracted with 100 ml of water. The aqueous layer was acidified with conc. hydrochloric acid and extracted with 120 ml of methylene chloride. The organic layer was dried over anhydrous magnesium sulfate and evaporated under reduced pressure to give 4.6 g (yield 35%) of objective α-dimethylcarbamoyl-3,5-dimethoxy-4-hydroxycinnamic acid.

1. concentrationThe mixture was concentrated under reduced pressure
2. custompurified by silica gel column chromatography (methanol/chloroform=2-4%)
3. customAn oily product thus obtained
4. extractionThe mixture was extracted with 100 ml of water
5. extractionextracted with 120 ml of methylene chloride
6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
7. customevaporated under reduced pressure

ORD record

ord-58e74a6cca9041ad9efaeeece1eaad87

Source dataset

uspto-grants-1995_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05478856