1-Phenyl-1<i>H</i>-pyrazole-4-carbaldehyde

In the title mol-ecule, C(10)H(8)N(2)O, the five- and six-membered rings form a dihedral angle of 10.14 (9)°. The aldehyde group is almost coplanar with the pyrazole ring to which it is connected [O-C-C-C torsion angle = -179.35 (17)°]. In the crystal, inversion dimers are linked by four C-H⋯O inter-actions as the carbonyl O atom accepts two such bonds. The dimeric aggregates are linked into supra-molecular layers in the ac plane by C-H⋯π and π-π [ring centroid(pyrrole)⋯ring centroid(phen-yl) = 3.8058 (10) Å] inter-actions.