Highly Regioselective Synthesis of 1-Aryl-3,4,5-Substituted Pyrazoles
Francis Gosselin*, Paul D. O'Shea, Robert A. Webster, Robert A. Reamer, Richard D. Tillyer, Edward J. J. Grabowski
*Department of Process Research, Merck Frosst Centre for Therapeutic Research, 16711 route transcanadienne, Kirkland, Québec, H9H 3L1, Canada, Email: francis_gosselinmerck.com
F. Gosselin, P. D. O'Shea, R. A. Webster, R. A. Reamer, R. D. Tillyer, E. J. J. Grabowski, Synlett, 2006, 3267-3270.
DOI: 10.1055/s-2006-956487
Abstract
A highly regioselective synthesis of 1-aryl-3,4,5-substituted pyrazoles based on the condensation of 1,3-diketones with arylhydrazines proceeds at room temperature in N,N-dimethylacetamide and furnishes pyrazoles in good yields.
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Key Words
1,3-diketones, arylhydrazines, pyrazoles, cyclocondensation, regioselectivity, amide solvents
ID: J60-Y2006-4790