Metamagnetism and canted antiferromagnetic ordering in two monomeric CoII complexes with 1-(2-pyrimidyl)piperazine. Hirshfeld surface analysis and theoretical studies.

Here we present the magnetic properties of two cobalt complexes formulated as: [Co(SCN)2(L)2] (1) and (H2L)2[Co(SCN)4]·H2O (2) (L = 1-(2-pyrimidyl)piperazine). The two compounds contain isolated tetrahedral CoII complexes with important intermolecular interactions that lead to the presence of a canted antiferromagnetic order below 11.5 and 10.0 K, with coercive fields at 2 K of 38 and 68 mT, respectively. Theoretical calculations have been used to explain this behaviour. Hirshfeld surface analysis shows the presence of strong intermolecular interactions in both compounds. The crystal geometries were used for geometry optimization using the DFT method. From the topological properties, electrostatic potential maps and molecular orbital analysis, information about the noncovalent interaction and chemical reactivity was obtained.

Self-assembly of new cobalt complexes based on [Co (SCN)4], synthesis, empirical, antioxidant activity, and quantum theory investigations.

The cobalt (II) complexes have been synthesized from the reaction of the cationic entities (3,4-dimethylaniline (1) and histamine (2)) with metallic salt CoCl2⋅6H2O and thiocyanate ion (SCN-) as a ligand in H2O/ethanolic solution and processing by the evaporation crystal growth method at room temperature to get crystals. The synthesized complex has been fully characterized by single-crystal X-ray diffraction. UV-Visible, FTIR spectroscopy, TGA analysis, and DFT circulations were also performed. The crystal structural analysis reveals that the solid (1) {[Co(SCN)4] (C8H12N)3}·Cl crystallizes in the monoclinic system with the space group P21/n and the solid (2) {[Co(SCN)4](C5H11N3)2}·2Cl crystallizes in the monoclinic space group P21/m. Metal cations are joined into corrugated chains parallel to the b-axis direction in (1) and (2) by four thiocyanate anions. The crystal structures of (1) and (2) were calculated using XRPD data, indicating that they are closely connected to the DRX mono-crystal results. Different interactions pack the system into a ring formed by N-H⋯Cl and N-H⋯S hydrogen bonds. C-H⋯π and the π⋯π stacking of anilinuim ring for (1) and N-H⋯S intermolecular interactions for (1) and (2) increase the crystals' robustness. Hirshfeld surface analysis cum 2D fingerprint plots visualize the main intermolecular interactions with their contributions in the solid-state phase. The molecular geometries of both complexes obtained from the crystal structure were used for quantum chemical calculation. Here, frontier orbital analysis and electrostatic potential illustrate the chemical reactivities of metal-organic complexes. QTAIM and NCI analysis reveal the strength of interactions at the electronic level.

Biocompatible conjugated fluorenylporphyrins for two-photon photodynamic therapy and fluorescence imaging.

The photophysical properties of a new series of fluorenyl porphyrins bearing water-solubilising oligoethyleneglycol chains are described. These biocompatible compounds present very good two-photon absorption and singlet oxygen generation properties, while retaining some fluorescence in water. After testing in vitro on breast cancer cells, some of them were shown to be efficient non-toxic two-photon photosensitisers allowing for fluorescence imaging, thus demonstrating their theranostic potential.

4-Chloro-anilinium hydrogen oxalate hemihydrate.

In the title hydrated mol-ecular salt, C(6)H(7)ClN(+)·C(2)HO(4) (-)·0.5H(2)O, the water O atom lies on a crystallographic twofold axis. In the crystal, the anions are linked by O-H⋯O hydrogen bonds, forming chains propagating along the b axis. These chains are inter-connected through O-H⋯O hydrogen bonds from the water mol-ecules and N-H⋯O hydrogen bonds from the cations, building layers parallel to the ab plane.

Bis(2,5-dimethyl-anilinium) tetra-chlorido-zincate(II).

In the title compound, (C(8)H(12)N)(2)[ZnCl(4)], the Zn(2+) ion adopts a distorted tetra-hedral coordination geometry. In the crystal, the cations and anions are linked by N-H⋯Cl hydrogen bonds, leading to ribbons propagating parallel to the a axis.

2,5-Dimethyl-anilinium nitrate.

In the title salt, C(8)H(12)N(+)·NO(3) (-), all non-H atoms of the cation lie on mirror planes. The nitrate counteranion has m symmetry and acts as a hydrogen-bond acceptor of N-H⋯O hydrogen bonds, connecting the cations and anions into layers running parallel to the ab plane.

2,6-Dimethyl-anilinium chloride monohydrate.

In the title hydrated mol-ecular salt, C(8)H(12)N(+)·Cl(-)·H(2)O, the component species inter-act by way of N-H⋯O, N-H⋯Cl and O-H⋯Cl hydrogen bonds, resulting in a three-dimensional network.

2,5-Dimethyl-anilinium chloride monohydrate.

In the title compound, C(8)H(12)N(+)·Cl(-)·H(2)O, the crystal packing is influenced by O-H⋯Cl, N-H⋯Cl and N-H⋯O hydrogen bonds, resulting in a two-dimensional network propagating parallel to (001).