Acetic Acid → L-Theanine

Temperatur

60 °C

First, 20.0 g (0.124 mol) of L-glutamic acid-γ-methyl ester was suspended in 20 g of methanol. To this, 13.7 g (0.137 mol) of acetylacetone and 12.5 g (0.124 mol) of triethylamine were added. The mixture was stirred at 60° C. for one hour. Subsequently, 80 g (1.24 mol) of 70% ethylamine was added to the mixture. After the mixture was allowed to react for 6 hours, excessive ethylamine was distilled away under reduced pressure. To this, 29.8 g (0.496 mol) of acetic acid, 30 mL of water and 120 mL of IPA were added. The mixture was heated for one hour and cooled on ice. The crystal precipitated was filtrated by suction and washed with 20 mL of IPA to obtain wet matter. The wet matter was dried under reduced pressure to obtain 13.1 g of theanine as a white crystal substance (yield: 61%). The obtained theanine had the same purity as high as in Example 1.

1. customto react for 6 hours
2. distillationexcessive ethylamine was distilled away under reduced pressure
3. temperatureThe mixture was heated for one hour
4. temperaturecooled on ice
5. customThe crystal precipitated
6. filtrationwas filtrated by suction
7. washwashed with 20 mL of IPA
8. customto obtain wet matter
9. customThe wet matter was dried under reduced pressure

ORD-Eintrag

ord-807ed9a9e24a42a380c6821d9246d4ea

Quelldatensatz

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08178722B2