A new 2D cadmium chloride network with 2-aminopyrimidine displaying long lifetime photoluminescence emission

CuII and ZnII β-diketonate coordination polymers based on pyrimidin-2-amine, pyrazine and 1,2-bis(4-pyridyl)ethane

Copper(II) and zinc(II) bis(4,4,4-trifluoro-1-phenylbutane-1,3-dionato) compounds with pyrimidin-2-amine (pyr2a), pyrazine (pyz) and 1,2-bis(4-pyridyl)ethane (dpet) were prepared and solid-state structures of coordination polymers [M(tfpb)₂(pyr2a)]_∞ [M = Cu (1), Zn (2); tfpb = 4,4,4-trifluoro-1-phenylbutane-1,3-dionate], [M(tfpb)₂(pyz)]_∞ [M = Cu (3), Zn (4a, 4b)] and [Cu(tfpb)₂(dpet)]_∞ (5), respectively, were determined by single-crystal X-ray analysis. The coordination of metal centers in all compounds is octahedral with nitrogen ligands occupying the axial positions. Compound (1) crystallizes in the triclinic space group P\bar 1, whereas (2) crystallizes in the monoclinic space group P2/n. Differences are due to the different orientation of adjacent M(tfpb)₂ units, whereas the orientation of pyrimidin-2-amine is the same in both compounds. Polymeric chains in (1) and (2) contain intramolecular N-H...O hydrogen bonding between amino and carbonyl groups. Room-temperature structures (3) and (4a) are isomorphous adopting the monoclinic space group C2/m; however, on cooling crystals (4a) to 150 K a single-crystal-to-single-crystal transformation to (4b) possessing the triclinic space group P\bar 1 was observed. Compound (5) crystallizes in the triclinic space group P\bar 1 and contains a parallel aggregation of chains in contrast to the known structure of the non-fluorinated benzoylacetonato ligand, where chains aggregate in a perpendicular fashion. In the compounds studied intramolecular C-H...O and/or C-H...F interactions are present. The neighboring chains are linked by π...π interactions and in some compounds also by C-H...π interactions [(1), (4b), (5)].

catena-Poly[[(2-amino-pyrimidine-κN(1))(thio-cyanato-κS)mercury(II)]-μ-thio-cyanato-κ(2)S:N]

In the title coordination polymer, [Hg(NCS)(2)(C(4)H(5)N(3))], the Hg(II) atom is four-coordinated by one aromatic N atom from a 2-amino-pyrimidine ligand, one S atom from a terminal thio-cyanate ligand, and one S atom and one N atom from a bridging thio-cyanate ligand. The crystal structure features polymeric chains running along the b axis which are stabilized by N-H⋯N hydrogen bonds.

Poly[(μ2-2-aminopyrimidine-κ2N1:N3)di-μ2-chlorido-mercury(II)]

The title compound, [HgCl₂(C₄H₅N₃)]_n, features a two-dimensional network parallel to (001) that is based on an Hg^II atom octahedrally coordinated by four μ₂-Cl atoms and two μ₂-2-amino­pyrimidine (apym) ligands in trans positions, yielding a distorted HgCl₄N₂ octa­hedron. The coordination network can be described as an uninodal 4-connected net with the sql topology. The Hg^II ion lies on a site of -1 symmetry and the apym ligand lies on sites of m symmetry with the mirror plane perpendicular to the pyrimidine plane and passing through the NH₂ group N atom. This polymeric structure is stabilized by N—H⋯Cl hydrogen bonds and columnar π–π stacking of pyrimidine rings, with a centroid–centroid distance of 3.832 (2) Å.