Ethyl Acetate → HCID 10759234, compound

N'-Acetylhydrazinecarboxylic acid tert-butyl ester(0.95 g, 5.45 mmol) was dissolved in methylene chloride (10 ml) and trifluoroacetic acid (10 ml) was added and the mixture was stirred at room temperature for 1 h. The mixture was concentrated in vavuo and stripped three times with methylene chloride to give 1.0 g of acetic acid hydrazide. Then (2R)-2-(tert-butoxycarbonylmethylamino)-3-phenyl propionic acid (0.76 g, 2.73 mmol) was dissolved in a mixture of dimethyl formamide (3 ml) and methylene chloride (6 ml) and a mixture of 1-hydroxy-7-azabenzotriazole (0.45 g, 3.28 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.62 g, 3.28 mmol) was added and stirred for 20 min. Then a mixture of acetic acid hydrazide (1.0 g, 5.45 mmol) and diisopropylethylamine (1.87 ml) was added and the mixture was stirred overnight. Ethyl acetate (50 ml) was added and the mixture was washed with water (50 ml). The aqueous layer was extracted with ethyl acetate (3×50 ml) and the combined organic layers were washed with water (2×50 ml) and brine (50 ml) and dried (MgSO4), filtered, concentrated to an oil, and chromatographed on silica (40 g) with heptane:ethyl acetate (1:1) to give 0.81 g of N-[(1R)-2-(N'-acetylhydrazino)-1-benzyl-2-oxoethyl]-N-methylcarbamic acid tert-butyl ester as a yellow oil.

1. additionwas added
2. additionwas added
3. stirringthe mixture was stirred overnight
4. washthe mixture was washed with water (50 ml)
5. extractionThe aqueous layer was extracted with ethyl acetate (3×50 ml)
6. washthe combined organic layers were washed with water (2×50 ml) and brine (50 ml)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated to an oil
10. customchromatographed on silica (40 g) with heptane:ethyl acetate (1:1)

ORD record

ord-633490f26b6a41a9ac0924114ddd3ba8

Source dataset

uspto-grants-2000_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06083908