L-Phenylalanine → N-(2,4-Dinitrophenyl)-L-phenylalanine

To a mixture of L-phenylalanine (8.88 g, 53.7 mmol) and 1-fluoro-2,4-dinitrobenzene (3.24 ml, 26.9 mmol) was added triethylamine (7.86 ml, 56.4 mmol). The resulting mixture was warmed using a Biotage Initiator microwave to 100° C. for 4 min. The solid was diluted with MeOH and the slurry was dropped into distilled water. Dichloromethane was added to the slurry and the organic phase was separated. The organic phase was further extracted with 1.2 M hydrogen chloride solution and brine. The organic phase was dried over Na2SO4, filtered and the solvents were evaporated. The residue was diluted with dichlormethane and the slurry was filtered. The precipitate was then washed with a small amount of dichlormethane. The combined filtrates were evaporated and the residue was purified by flash chromatography using a dichloromethane/methanol gradient (0% to 5%) to afford the title compound.

1. temperatureThe resulting mixture was warmed
2. customto 100° C.
3. customfor 4 min
4. additionthe slurry was dropped
5. distillationinto distilled water
6. additionDichloromethane was added to the slurry
7. customthe organic phase was separated
8. extractionThe organic phase was further extracted with 1.2 M hydrogen chloride solution and brine
9. dry with materialThe organic phase was dried over Na2SO4
10. filtrationfiltered
11. customthe solvents were evaporated
12. additionThe residue was diluted with dichlormethane
13. filtrationthe slurry was filtered
14. washThe precipitate was then washed with a small amount of dichlormethane
15. customThe combined filtrates were evaporated
16. customthe residue was purified by flash chromatography

ORD record

ord-9f2ff8d211394187b56c4faa692e1502

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09221812B2