Hydrazine hydrate (1:1) → 4-Amino-2-[(tert-butoxycarbonyl)(methyl)amino]butanoic acid

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Reaction Steps

11.8 g (32.6 mmol) of the compound from example 5A was dissolved in approx. 640 ml ethanol and 23.8 ml (488 mmol) hydrazine hydrate was added to the reaction mixture. After stirring over night, the reaction mixture was filtered and the filtrate was concentrated to dryness under reduced pressure. The raw product was dissolved in ethanol and approx. 50 g silica gel was added, the solvent was removed under reduced pressure. The resulting solid was added onto a approx. 500 g silica gel column and chromatographed. Solvents used were dichloromethane/methanol 9/1 to dichloromethane/methanol 1/1. The product-containing fractions were combined and concentrated to dryness under reduced pressure. This gave 2.98 g (12.8 mmol, 39% of theory) product.

Provenance & Evidence