Ammonium Chloride → HCID 18540457, compound

To a vigorously stirred solution of (S)-2-tert-butoxycarbonylamino-3-(4-hydroxy-3-nitro-phenyl)-propionic acid ethyl ester (1.00 g, 2.82 mmol) in methanol (50 mL) was added a solution of ammonium chloride (2.26 g, 42.3 mmol) in water (25 mL) followed by zinc dust (<10 μM particle size) (1.84 g, 28.1 mmol). After stirring at ambient temperature for 30 minutes the reaction mixture was filtered through a pad of Celite® and residual soluble material eluted from the pad with methanol. The filtrate was concentarted in vacuo and the aqueous residue poured into water (100 mL), diluted with brine (50 mL) and extracted with ethyl acetate (3×50 mL). The combined organic extracts were washed with brine (75 mL), dried over sodium sulfate and concentrated in vacuo to give crude 3-(3-amino-4-hydroxy-phenyl)-2-tert-butoxycarbonylamino-propionic acid ethyl ester as a green viscous solid which was used without further purification (0.89 g, 97%).

1. filtrationwas filtered through a pad of Celite® and residual soluble material
2. washeluted from the pad with methanol
3. additionthe aqueous residue poured into water (100 mL)
4. additiondiluted with brine (50 mL)
5. extractionextracted with ethyl acetate (3×50 mL)
6. washThe combined organic extracts were washed with brine (75 mL)
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated in vacuo

ORD record

ord-666acbd6cf6a4e839a7313b6f717c5ee

Source dataset

uspto-grants-2008_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07371869B2