The title co-crystal, 3-(4-fluoro-phen-yl)-1H-pyrazole-5-(4-fluoro-phen-yl)-1H-pyrazole (1/1), C9H7FN2, crystallizes with four independent mol-ecules (A, B, C and D) in the asymmetric unit exhibiting two tautomeric forms (A and D; B and C) due to N-H proton exchange between the two N atoms of the pyrazole ring. The dihedral angles between the mean planes of the pyrazole and benzene rings are 15...

The title compound, C21H12Cl2N2O3, is a 1,4-diaroyl pyrazole derivative and has three aromatic rings. The dihedral angles between the naphthalene ring system and the pyrazole ring, the pyrazole and phenyl rings and the naphthalene ring system and the phenyl ring are 49.44 (13), 49.87 (16) and 0.58 (11)°, respectively. The phenolic proton forms an intra-molecular O-H⋯O hydrogen bond with an adja...

In the title compound, C21H12Br2N2O3, a 1,4-diaroyl pyrazole derivative, the dihedral angles between the naphthalene ring system and the pyrazole ring, the pyrazole and benzene rings, and the naphthalene ring system and benzene ring are 50.0 (2), 51.1 (2) and 1.34 (16)°, respectively. The phenolic proton forms an intra-molecular O-H⋯O hydrogen bond with the adjacent carbonyl O atom. In the crys...

In the title compound, C(16)H(11)ClN(2)O(2), the pyrazole ring makes dihedral angles of 11.88 (13) and 22.33 (13)° with the 3-chloro-2-hy-droxy-benzene group and phenyl rings, respectively. The phenolic hy-droxy group forms an intra-molecular O-H⋯N hydrogen bond with the imine N atom of the pyrazole unit. The formyl group is virtually coplanar with the pyrazole ring [dihedral angle = 4.5 (19)°]...

The reaction of Co(NO(3))(2)·3H(2)O with pyridine-2,6-dicarboxylic acid and 3,5-dimethyl-1H-pyrazole in a 1:1:3 molar ratio affords the title complex, [Co(C(7)H(3)NO(4))(C(5)H(8)N(2))(3)]·H(2)O. The Co(II) atom is coordinated by one pyridine-2,6-dicarboxyl-ate chelating ligand and three 3,5-dimethyl-1H-pyrazole ligands in a distorted octa-hedral geometry. Hydrogen-bonding interactions involving...

The title structure, C(15)H(7)N(7)O(10)·C(3)H(6)O, was prepared by penta-nitration of 3,5-diphenyl-1H-pyrazole. The proton attached to a pyrazole N atom forms a hydrogen bond with the O atom of the acetone solvent mol-ecule, owing to the NO(2) enhanced acidity of the proton. The NO(2) group on the phenyl C atom is twisted by 33.9 (2)° from coplanarity with the ring in order to avoid a short int...

Proton transfer in pyrazole systems involving interaction with a paramagnetic transition metal complex has been studied with 1H and 13C NMR techniques. Kinetics of the ligand exchange in the pyrazole complex of bis-(acetylacetonato)nickel (II) has been investigated, and hyperfine coupling constants for the interaction of the nickel unpaired electron with the ligand nuclei in the complex have be...

The title Schiff base compound, C(23)H(23)N(5)O, was synthesized by the reaction of 4-amino-phenazone and 3,5-dimethyl-1-phenyl-pyrazole-4-carbaxaldehyde. The mol-ecule adopts an E configuration about the central C=N double bond. A weak intra-molecular C-H⋯O hydrogen bond generates an S(6) ring motif. The dihedral angle between the pyrazole rings is 24.72 (10)° and the dihedral angles between t...

In this paper, we report the anisochrony of the fluorine atoms of a CHF₂ group when linked to a pyrazole ring. The pyrazole is part of (4S,7R)-7,8,8-trimethyl-4,5,6,7-tetrahydro-4,7-methano-2H-indazole also known as (4S,7R)-campho[2,3-c]pyrazole, which has two stereogenic centers. Gauge-Independent Atomic Orbital (GIAO)/Becke, 3-parameter, Lee-Yang-Parr (B3LYP)/6-311++G(d,f) calculated 19F chem...