4-(2,6-Dichlorophenyl)(hydroxyimino)methyl-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one
Abstract
The title compound, C18H15Cl2N3O2, was derived from the product of the intermolecular 3 + 2-cycloaddition reaction of 2,6-dichlorobenzonitrile oxide and 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one. The hydroxy group and the 2,6-dichlorophenyl ring of the oxime are in a trans conformation and the C=N-O angle is 113.90 (15) A. Pairs of molecules form centrosymmetric O-HN hydrogen-bonded dimers, with an ON distance of 2.821 (2) A. The pyrazole ring is nearly planar, with a mean deviation from the plane of 0.0246 (3) A and a dihedral angle between the pyrazole and the unsubstituted phenyl ring of 131.7 (4)Degrees.