4-Fluoro-3-nitrobenzoic acid → HCID 86714406, compound

Participants

Reaction Steps

To a solution of 9.26 g of 4-fluoro-3-nitro-benzoic acid in 100 ml of dry DMF 7.43 g of HOBT, 10.54 g of EDC and 8.9 ml of DIPEA were added at 0° C. After 30 min 12.31 g of L-leucin-tert.-butylester-hydrochloride and 8.9 ml of DIPEA were added and the reaction was stirred at it for 4 h. The reaction was then concentrated to about a fifth of its volume and poured into water. It was then extracted with ethyl acetate three times. The combined organic phases were washed with saturated aqueous sodium carbonate solution and brine, dried over magnesium sulphate and concentrated to yield 17.65 g (100%) of (S)-2-(4-Fluoro-3-nitro-benzoylamino)-4-methyl-pentanoic acid tert-butyl ester as a brown oil, which was used without further purification in the subsequent step.

Provenance & Evidence