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Ethyl 2-Cyano-2-(4-nitrophenylsulfonyloxyimino)acetate-Mediated Lossen Rearrangement: Single-Pot Racemization-Free Synthesis of Hydroxamic Acids and Ureas from Carboxylic Acids

Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev and Bhubaneswar Mandal*

*Department of Chemistry Indian Institute of Technology Guwahati, Guwahati 781039, India, Email:

K. Thalluri, S. R. Manne, D. Dev, B. Mandal, J. Org. Chem., 2014, 79, 3765-3775.

DOI: 10.1021/jo4026429

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Hydroxamic acids were synthesized from carboxylic acids and hydroxylamine hydrochloride in the presence of ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (4-NBsOXY). 4-NBsOXY also promotes the Lossen rearrangement of hydroxamic acids in the presence of amines to yield ureas. The reactions are compatible with common N- and O-protecting groups and prevent racemization.

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Ethyl 2-Cyano-2-(2-nitrobenzenesulfonyloxyimino)acetate (o-NosylOXY): A Recyclable Coupling Reagent for Racemization-Free Synthesis of Peptide, Amide, Hydroxamate, and Ester

D. Dev, N. B. Palakurthy, K. Thalluri, J. Chandra, B. Mandal, J. Org. Chem., 2014, 79, 5420-5431.

Key Words

hydroxamic acids, ureas (amination)

ID: J42-Y2014