Letter | Published:

Side-Reactions during Hydrogenolysis of 2,4-Dinitrophenylhydrazones of Aromatic Keto-Acids

Naturevolume 191pages285286 (1961) | Download Citation



THE identification of the keto-acid 2,4-dinitrophenylhydrazones is greatly facilitated by conversion to their respective amino-acids. The most commonly employed procedure is that first noted by Emil Fischer1 and modified for application to organic systems by Towers et al.2. This involves low-pressure hydrogenolysis over a platinum catalyst, followed by paper chromatography of the amino-acids produced. The yields of the respective amino-acids vary between 30 and 98 per cent, and in general the conversion is free from side-reactions.

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    Towers, G. H. N., Thompson, J. F., and Steward, F. C., J. Amer. Chem. Soc., 76, 2392 (1954).

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    Menkes, J. H., A.M.A., J. Dis. Child., 99, 500 (1960).

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  1. Department of Pediatrics, The Johns Hopkins Hospital, Baltimore, 5, Maryland



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