Structural Chemistry

, Volume 8, Issue 3, pp 189–195 | Cite as

Tautomerism and the Mills-Nixon-like effect in pyrazoles



Theoretical calculations on a wide variety of NH-pyrazoles clearly show a relationship between ring strain and annular tautomerism, i.e., the most stable tautomer is that having the largest singleond character in the C3-C4 bond.

Key words

Mills-Nixon-like effect AM1 calculations ab initio calculations annular tautomerism NH-pyrazoles 


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Copyright information

© Plenum Publishing Corporation 1997

Authors and Affiliations

  1. 1.CSICInstituto de Química MédicaMadridSpain

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