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Assembly of orotic acid (H3Or, 1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidinecarboxylic) and Cd(NO3)·6H2O yielded a coordination polymer, [(Cd(Hor)·2.5H2O)2]n (1), which has been characterized by X-ray single-crystal diffraction, TGA, and fluorescence spectra. Single-crystal X-ray structural analyses reveal that 1 is a hydrogen-bonded binuclear Cd-orotate coordination polymer in which both Cd2+ ions have different coordination environments with identical distorted octahedral geometry. Crystal data for 1: monoclinic, space group P21/n, a = 7.0209(10) Å, b = 13.974(2) Å, c = 17.541(3) Å, β = 98.842(2)°, V = 1700.5(4) Å, Z = 4, R1 = 0.0269, wR2 = 0.0612, θmax = 25.960. The emission spectrum of the Cd-complex recorded with 265 nm excitation wavelength reveals the complex has strong blue luminescence with the peak maximum 420 nm (2.95 eV) as a result of the n–π* and π–π* transitions on the H3Or ligand. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of new supramolecular networks based on mixed ligands as orotate with 1,3-di(4-pyridyl)propane or malonic acid are reported. Both coordination polymers was characterized using X-ray crystallography, magnetic measurements, electron paramagnetic resonance, and density functional theory calculations. The significant role of hydrogen bonding O H⋯O and N H⋯O in formation of 2D coordination network and magnetic exchange pathway was found. [Display omitted] Two new coordination network based on mixed ligands, orotic acid potassium salt with 1,3-Di(4-pyridyl)propane (dpp) and malonic acid at room temperature were synthesized as [Cu 2 (dpp)(HOr) 2 ·2H 2 O]n (1) and [Cu(HOr)(H 2 O) 2 ]n (2) respectively. To strategically design and synthesize Cu(II)-coordination networks where N H⋯O and O H⋯O hydrogen bonds act as connecting tools in the construction of three dimensional networks have been discussed. The both complexes have been characterized by single crystal X-ray analysis, elemental analysis, magneto-structural study along with EPR study. The magnetic data reveals that the complex 1 shows antiferromagnetic exchange interactions while complex 2 shows ferromagnetic exchange interaction through {⋯H N C O} dimer. The DFT calculation and HOMO/LUMO molecular orbitals analysis is used to rationalized the magnetic behavior in these coordination polymers. [ABSTRACT FROM AUTHOR]

• Magneto-structural analyses of two coordination polymers based on Orotic acid are well explored. • Cu-orotate is first anionic, orotate based coordination polymer exhibit weak ferromagnetic behavior. • Ni-orotate coordination polymer becomes evidence for weak antiferromagnetic behavior. • DFT calculation underline the pathway of magnetic exchange interactions through N—H⋯O, O—H⋯O supramolecular synthons and confirm that the magnetic interactions propagate through such contacts in complex 1 and 2. Orotato based coordination network of formula [Cu(HOr) 2 2−. 2(CH 3) 2 ―NH 2 + n (1), and [Ni(HOr) . 3H 2 O] n (2), have been synthesized hydrothermally by self-assembly of orotic acid (H 3 Or) with metal salts Cu(OAc) 2 . H 2 O and Ni(NO 3) 2 • 6H 2 O respectively. Single crystal X-ray study confirms that in 1 electroneutrality is obtained with a compensating cation i.e. (CH 3) 2 ‒NH 2 + and trans-trans μ2η1:η1 bridging carboxylate extend the Cu-Orotate moiety into 2D coordination network showing square lattice topology (sql) which through { ... H‒N‒C = O} dimer yields into 3D hydrogen bonded coordination polymer.Temperature dependent measurements of magnetic susceptibility reveals the occurrence of competitive exchange interactions with weak ferromagnetic character in 1 (J = +0.31 cm–1) and weak antiferromagnetic interaction in 2 (J = - 0.52 cm–1). The dominantzero – field splitting effect is observed in Ni(II) ion. Two important magneticsuper exchange pathway transmitted through carboxylate oxygen of ligand through N‒H ... O, and O‒H ... O supramolecular synthons along with long Cu•••Cu separation of 6.635 Å (1) or Ni•••Ni separation of 7.700 Å (2). The DFT calculation analysis is used to rationalized the magnetic behavior in these coordination polymers. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A novel, potassium orotate (OrK) and 1,3 di (4-pyridyl) propane (dpp) based, coordination network of Zn synthesized at room temperature. The emission spectrum of the Zn-complex recorded with 290 nm excitation wavelength reveals that complex has strong luminescence with the peak maximum 380 nm (3.2627 eV) and thermal stability of 1 upto 350 °C owing to different coordination environment around zinc atoms and crystal packing. • The syn-anti μ2η1:η1 bridging carboxylate and pyridyl extended the Or-Zn-dpp moiety into 2D coordination network showing square grid sheet. • The emission spectrum of Zn-complex was recorded with 290 nm excitation wavelength which reflects that 1 has strong luminescence with peak maximum of 380 nm (3.2627 eV). A novel mixed ligand based coordination network of Zn, having formula [Zn 8 (Or) 8 (dpp) 4 (H 2 O) 8 n (1), have been engineered and synthesized at room temperature by self-assembly of potassium orotate (OrK) and 1,3 di(4-pyridyl)propane (dpp) with metal salt, Zn(OAc) 2 ·2H 2 O Single crystal X-ray structural analysis reveals that coordination sphere around Zn(II) ions, in Or-Zn-dpp moiety, having different atomic arrangement with distorted square pyramidal geometry. The syn-anti μ2η1:η1 bridging carboxylate and pyridyl moieties extended the Or-Zn-dpp skeleton into 2D coordination network showing square grid sheet. The emission spectrum of Zn-complex was recorded with 290 nm excitation wavelength which reflects that 1 has strong luminescence with peak maximum of 380 nm (3.2627 eV) and is a result of the n – π * and π – π * transitions of H 3 Or and dpp ligand. Thermogravimetric analysis shows that when the coordinated water molecule completely comes out from the complex around 320 °C, the dehydrated forms steadily starts to degrade, and the complete decomposition is observed above 350 °C. [ABSTRACT FROM AUTHOR]