Superior Reactivity of Thiosemicarbazides in the Synthesis of 2-Amino-1,3,4-oxadiazoles
Sarah J. Dolman,* Francis Gosselin, Paul D. O'Shea and Ian W. Davies
*Department of Process Research, Merck Frosst Centre for Therapeutic
Research, 16711 Route Transcanadienne, Kirkland, Québec, Canada H9H 3L1, E-mail:
sarah_dolman
merck.com
S. J. Dolman, F. Gosselin, P. D. O'Shea, I. W. Davies, J. Org. Chem., 2006, 71, 9548-9551.
DOI: 10.1021/jo0618730
Abstract
A facile and general protocol for the preparation of 2-amino-1,3,4-oxadiazoles relies on a tosyl chloride/pyridine-mediated cyclization of thiosemicarbazides that consistently outperforms the analogous semicarbazide cyclizations. Various 5-alkyl- and 5-aryl-2-amino-1,3,4-oxadiazoles have been prepared in good yields.
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Key Words
ID: J42-Y2006-4020
