L-Valine → N-(tert-Butylcarbamoyl)-L-valine

4.69 g of L-valine was dissolved in 40 ml of a 1N sodium hydroxide aqueous solution, and 5 ml of tetrahydrofuran was added to the solution. While stirring, 4.00 g of tert-butyl isocyanate was added, and the stirring was continued overnight at room temperature. After 10 ml of a 1N sodium hydroxide aqueous solution was added to the reaction mixture, the mixture was washed twice with 50 ml of ethyl acetate and acidified with 6N hydrochloric acid. Then, the reaction mixture was extracted twice with 100 ml of ethyl acetate. The extracts were washed twice with 50 ml of a saturated sodium chloride aqueous solution. After drying over anhydrous sodium sulfate and then concentrating under reduced pressure, recrystallization was carried out from an ethyl acetate-hexane mixture to obtain 6.6 g of N-tert-butylcarbamoyl-L-valine as white crystals.

1. additionwas added to the solution
2. washthe mixture was washed twice with 50 ml of ethyl acetate
3. extractionThen, the reaction mixture was extracted twice with 100 ml of ethyl acetate
4. washThe extracts were washed twice with 50 ml of a saturated sodium chloride aqueous solution
5. dry with materialAfter drying over anhydrous sodium sulfate
6. concentrationconcentrating under reduced pressure, recrystallization

ORD record

ord-b7066bfbacfc4e73bf0d972a9eb0696a

Source dataset

uspto-grants-1985_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04512898