First crystal structures of metal complexes with a 4-nitropyrazole-3-carboxylic acid ligand and the third crystal form of the ligand

Abstract

Supporting information: this article has supporting information at journals.iucr.org/c First crystal structures of metal complexes with a 4-nitropyrazole-3-carboxylic acid ligand and the third crystal form of the ligand

Synthesis, crystal structure and biological activity of copper(II) complex with 4-nitro-3-pyrazolecarboxylic ligand

“…The lengths of equatorial coordination bonds (Table III) are comparable to those found in the previously reported square-pyramidal [Cu2(4nitro-3pzc)2(dmf)(H2O)] complex comprising the same pz ligand. 10 Similarly to previous findings the pz lingand in [Cu2(4nitro-3pzc)2(H2O)6]2H2O displays asymmetrical coordination which is reflected in corresponding Cu1-N1 i -N2 i and Cu1-N2-N1 angles of 124.0(1) and 136.8(1)°, respectively (symmetry code: i = −x, −y, −z). The ring system is approximately flat.…”

“…The Cu•••Cu distance in this binuclear unit is 3.903(1) Å which is slightly shorter than in the square-pyramidal Cu(II) complex, 3.945(1) Å. 10 O n L i n e F i r s t In the recently reported crystal structure of [Co2(4nitro-3pzc)2(H2O)6]2H2O complex with the same pz bridge, 10 the Co(II) was found in the octahedral coordination environment equivalent to that of Cu(II) ion in the title complex. The comparison of the geometrical features of two octahedral complexes is given in the Supplementary material; here we note that their crystal arrangements are characterized by the same structural motifs, based on strong O-H⋅⋅⋅O hydrogen bonds (Table IV).…”

“…We have recently reported the structural properties of Cu(II) and Co(II) complexes where dianion of 4-nitro-3-pyrazolecarboxylic acid (Scheme 1a) was used as a bridging ligand. 10 These compounds are rare examples of the metal complexes comprising 3,4-disubstituted pz derivative as a bridge and also the first crystal structures of the transition metal complexes with ligands derived from 4-nitro-3-pyrazolecarboxylic acid (Scheme 1a). Continuing our interest in pyrazole-derived molecules, [10][11][12] and particularly the bridging and structural behaviour of 4-nitro-3-pyrazolecarboxylate ligand 10,11 we have synthesized a new binuclear complex [Cu2(4nitro-3pzc)2(H2O)6]2H2O, Scheme 1b.…”

“…The Cu(II) ion, is here found in the tetragonally distorted octahedral environment, dissimilar to previously reported five-coordinated Cu(II) complex with the same ligand. 10 The novel complex was characterized by single-crystal X-ray diffraction and infrared spectroscopy. The antifungal activity of the compound was also tested for fungi Ph.…”

Crystal structure of ethyl 3-(trifluoromethyl)-1H-pyrazole-4-carboxylate, C7H7F3N2O2

“…Also, the incorporation of carboxylic acid groups and carboxylic ester functionality facilitates further modification and improvement of bioactivity of the pyrazole based molecules [10]. As a part of our continuous research interest in the pyrazole derived compounds [11][12][13] we report here the crystal structure of ethyl 3-(trifluoromethyl)-1H-pyrazole-4carboxylate.…”