(4-Nitrophenyl)acetic acid → HCID 20610284, compound

Participants

Reaction Steps

A dimethyl formamide (82 mL) solution of 4-nitrophenylacetic acid (1.61 g, 8.87 mmol) in dimethyl formamide (82 mL) was stirred with 4-hydroxybenzotriazole monohydrate (1.40 g, 10.4 mmol) for 10 minutes. 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimde hydrochloride (1.86 g, 9.72 mmol) was added and the mixture was stirred until all 1-(3-dimethylaminopropyl)-3-ethylcarbodiimde hydrochloride had dissolved. To this solution, 2-allyloxycarbonylamino-3-(3-pyrrolidin-2-yl-isoxazol-5-yl)-propionic acid ethyl ester hydrochloride from Example 1C (3.16 g, 8.25 mmol) was added and the mixture stirred 30 minutes followed by addition of triethyl amine (1.26 mL, 9.04 mmol). After the reaction had stirred at room temperature over night it was poured into water and extracted with ethyl acetate three times. The combined extracts were washed with a saturated solution of sodium bicarbonate, water (2×) and brine. The organic portion was dried over magnesium sulfate and concentrated. The resulting residue was chromatographed on a Biotage Flash 40S column eluting with ethyl acetate/hexanes (5:1) to yield the title compound as a yellow oil (674 mg, 15%). MS (CI) m/z 501.3 (M+1). Additionally, starting material 2-allyloxycarbonylamino-3-(3-pyrrolidin-2-yl-isoxazol-5-yl)-propionic acid ethyl ester was recovered (2.15 g, 75%). MS (Cl) m/z 338.1 (M+1)

Provenance & Evidence