Water → Phenethyl (E)-caffeate

1.98 g of caffeic acid was dissolved in 100 mL of dimethylformamide. 2.28 mL of 25% aqueous sodium hydroxide solution was added while stirring. Stirring continued for 1 hr. At the end of this period a solution of 5.7 mL of phenethyl bromide in 10 mL dimethylformamide was added slowly in 30 minutes. The resulting reaction mixture was stirred at room temperature for 50 hrs. Next, the reaction mixture was poured into 200 mL of water and extracted with ethyl acetate (3×100 mL). The combined organic extract was washed with 100 mL of 1N HCl and water (3×100 mL). After drying over sodium sulfate, the solvent was distilled off under vacuum. The residue was crystallized from ethyl acetate/hexane by treatment with activated carbon to obtain caffeic acid phenethyl ester. The yield was 600 mg and the purity was greater than 90%.

1. stirringStirring
2. customThe resulting reaction mixture
3. stirringwas stirred at room temperature for 50 hrs
4. extractionextracted with ethyl acetate (3×100 mL)
5. extractionThe combined organic extract
6. washwas washed with 100 mL of 1N HCl and water (3×100 mL)
7. dry with materialAfter drying over sodium sulfate
8. distillationthe solvent was distilled off under vacuum
9. customThe residue was crystallized from ethyl acetate/hexane by treatment with activated carbon

ORD record

ord-b78b72be027f42ddba5d8b7d3f2eb77b

Source dataset

uspto-grants-2008_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07368593B1