S. Trofimenko, Glenn P.A. Yap, Fernando A. Jové
Aug 20, 2007
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0
Influential Citations
35
Citations
Journal
Tetrahedron
Abstract
Abstract The tautomerism in the solid state and in solution of five 4-bromo-1 H -pyrazoles has been studied by multinuclear magnetic resonance spectroscopy and, for one of them, by X-ray crystallography (3,4-dibromo-5-phenyl-1 H -pyrazole). When there is a bromine atom at position 3(5), in all cases, the tautomer present in the solid state is the 3-bromo one. In solution, the same tautomer is the major one. DFT calculations justify the predominance of 3-bromo tautomers over 5-bromo ones and provide some useful chemical shifts obtained through GIAO calculations.