Methanaminium, N-((dimethylamino)(3H-1,2,3-triazolo(4,5-b)pyridin-3-yloxy)methylene)-N-methyl-, hexafluorophosphate(1-) (1:1) → Ethyl (2S)-3-[3-({(3R)-N-[(benzyloxy)carbonyl]-4,4,4-trifluorovalyl}amino)-4-fluorophenyl]-2-methylpropanoate

Participants

Reaction Steps

0.87 g (2.85 mmol) of (3R)—N-[(benzyloxy)carbonyl]-4,4,4-trifluorovaline (diastereomer mixture) and 0.77 g (3.42 mmol) of (+)-ethyl (2S)-3-(3-amino-4-fluorophenyl)-2-methylpropanoate were dissolved in a mixture of 5 ml of DMF and 2.5 ml of pyridine, and 1.41 g (3.71 mmol) of HATU were added at RT. The reaction mixture was stirred at RT overnight and then diluted with ethyl acetate. The mixture was washed successively with 1 N hydrochloric acid, sat. sodium bicarbonate solution and sat. sodium chloride solution, dried over magnesium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 6:1). This gave 1.27 g of the target product (87.2% of theory, diastereomer ratio about 4.8:1).

Provenance & Evidence