5-Amino-1-phenyl-1H-pyrazole-4-carboxylic acid

Abstract

In the mol-ecule of the title compound, C10H9N3O2, the pyrazole ring is approximately coplanar with the amino and carboxyl groups. The phenyl group is twisted by 48.13 (3)° relative to this plane. An intra-molecular N - H⋯O hydrogen bond stabilizes the planar conformation of the mol-ecule. The mol-ecules are linked into two-dimensional sheets by two strong inter-molecular N - H⋯N and O - H⋯O hydrogen bonds. The latter forms the classic carboxylic acid dimer motif. © 2008.