Isonicotinamide Ligands Research Articles

Aqua-bis-(2,2'-bi-pyridine-κ2N,N')(isonicotinamide-κN)ruthenium(II) bis-(trifluoromethanesulfonate).

In the title complex, [Ru(C10H8N2)2(C6H6N2O)(H2O)](CF3SO3)2, the central RuII atom is sixfold coordinated by two bidentate 2,2'-bi-pyridine, an isonic-otinamide ligand, and a water mol-ecule in a distorted octa-hedral environment with tri-fluoro-methane-sulfonate ions completing the outer coordination sphere of the complex. Hydrogen bonding involving the water mol-ecule and weak π-π stacking inter-actions between the pyridyl rings in adjacent mol-ecules contribute to the alignment of the complexes in columns parallel to the c axis.

Poly[[(μ3-adamantane-1,3-di-acetato)[μ-N-(pyridin-3-yl)isonicotinamide]-nickel(II)] monohydrate], a layered coordination polymer with triangular (3,6) topology.

The title compound, {[Ni(C14H18O4)(C11H9N3O)]·H2O}n, contains octa-hedrally coordinated NiII ions ligated by 1,3-adamantanedi-acetato (ada) ligands and N-(pyridin-3-yl)isonicotinamide (3-pina) ligands, to form coordination polymer layers with a triangular (3,6) grid topology based on [Ni2(OCO)2] dimeric units. The diperiodic layer motifs stack in an ABAB pattern mediated by C-H⋯O supra-molecular inter-actions between ada ligands and water mol-ecules of crystallization to form the full triperiodic crystal structure of the title compound.

Poly[[(μ3-adamantane-1,3-di-carboxyl-ato)aqua-[μ-N-(pyridin-3-yl)isonicotinamide]-nickel(II)] monohydrate], a layered coordination polymer with (4,4) topology.

The title com-pound, {[Ni(C12H14O4)(C11H9N3O)(H2O)]·H2O}n, contains octa-hedrally coordinated NiII ions ligated by adamantane-1,3-di-carboxyl-ate (adc) and N-(pyridin-3-yl)isonicotinamide (3-pina) ligands forming coordination polymer layers with a (4,4) grid topology. These diperiodic layer motifs aggregate in an AAA pattern mediated by supra-molecular C-H⋯O inter-actions to form the full triperiodic crystal structure of the title com-pound.

Poly[[[μ3-3-(2-carboxyl-atophen-yl)propionato][μ2-N,N'-(ethane-1,2-di-yl)bis-(pyridine-4-carbox-amide)]copper(II)] monohydrate], a layered coordination polymer with (4,4) topology.

In the title compound, {[Cu(C10H8O4)(C14H14N4O2)]·H2O}n, the CuII cations are coordinated in a square-pyramidal fashion, with trans pyridyl-N donor atoms from two N-(2-(pyridin-3-yl-amino)-eth-yl)isonicotinamide (pein) ligands in the basal plane. The other three coordination sites are taken up by carboxyl-ate O-atom donors from three different 3-(2-carb-oxy-phen-yl)propionate (cpp) ligands. The central ethyl-enedi-amine segments of the pein ligands are disordered equally over two sets of positions. {Cu2O2} rhomboid clusters are connected into [Cu(cpp)(pein)]n (4,4) coordination polymer grids by the full span of the cpp and pein ligands. Individual layer motifs stack in an AAA pattern along the a axis by means of inter-layer hydrogen-bonding inter-actions.

A Novel Synthesis of iso-nicotinamide ligand and its cobalt complex

The complex of cobalt(II) with iso-nicotinamide (intmd) was synthesized at a 1:1 mole ratio of metal to ligand. The complex formula obtained is [Co(intmd)2(H2O)2]Cl2.nH2O (n = 0 or 1). The Co(II)-intmd complex was characterized by UV-Vis Spectrophotometer, Atomic Absorption Spectrophotometry (AAS), Differential Thermal Analyzer (DTA), Conductivity meter, Fourier-transform Infrared Spectroscopy (FTIR), Magnetic Susceptibility Balance (MSB), and Powder X-Ray Diffraction. Thermal analysis showed the complex contained several hydrates. The electrical conductivity of the complex in aquades is 1:1, the complex is electrolyte. The infrared spectrum shows that C=O and -NH2 from intmd are coordinated with metal ion. The electronic spectra show two peaks indicating the transitions 4T1g(F) → 4T1g(P) (ν3) and 4T1g(F) → 4A2g(F) (ν2). The complex is paramagnetic with μeff = 5.31-5.44 BM. It is suggested that the Co(II)-intmd complex has an octahedral geometry and an orthorhombic crystal system.

Iron(II) pyridinecarboxamide complexes: Synthesis, crystal structures and magnetic properties

Two new mononuclear complexes of iron(II) pyridinecarboxamides (picolinamide - pia, isonicotinamide - isn), [Fe(pia)3]·(SO4)·3H2O (1) and (isnH)2[Fe(isn)2(SO4)2(H2O)2]·H2O (2) have been synthesized by the reaction of iron(II) sulphate heptahydrate and pyridinecarboxamides in different solvents by standard method under reflux. Both compounds were characterized by single-crystal X-ray diffraction structure analysis, magnetic measurements and by FT-IR spectroscopy. In the complex cation of 1 Fe2+ ion is six coordinated by three nitrogen and three oxygen atoms from three bidentate picolinamide ligands in mer mode. In complex anion of 2 central Fe2+ ion is six coordinated by two isonicotinamide ligands, two sulphate ligands and two water molecules in trans mode. In both structures complex ions are connected with counterions and crystal water molecules with intermolecular hydrogen bonds. Magnetic properties of the compounds were measured between 2 K and 300 K giving the results: µeff = 4.5 BM for compound 1 and µeff = 4.7 BM for 2. Experimental values of the IR spectra are comparable with literature data and are in good agreement with results of the structural analysis.

Bis(isonicotinamide-κN)silver(I) tri-fluoro-methane-sulfonate aceto-nitrile disolvate.

The central AgI atom of the title salt, [Ag(INAM)2](CF3SO3)·2CH3CN, where INAM is isonicotinamide (C6H6N2O), is twofold coordinated by the pyridine N atoms of two isonicotinamide ligands creating a slightly distorted linear mol-ecular geometry. The formation of polymeric chains {[Ag(INAM)2]+} n , held together by discrete hydrogen bonds through the amide group of the INAM ligand leaves voids for non-coordinating aceto-nitrile mol-ecules that inter-act the silver metal center via regium bonds.

Isonicotinamide-Based Compounds: From Cocrystal to Polymer.

The reaction between [Cu(μ-OAc)(μ-Pip)(MeOH)]2 (1) (OAc = acetate; Pip = 1,3-benzodioxole-5-carboxylate) and isonicotinamide (Isn) in MeOH as solvent yielded two mixture pairs of three compounds: {(HPip)2(Isn) (2), [Cu(Pip)2(Isn)2] (3)} and {(3), {[Cu3(Pip)2(OAc)2(μ-Isn)2(Isn)2(μ-OCH3)2(MeOH)2]·2MeOH}n (4)}. Modifying the reaction conditions (t, T, molar ratio), 2 and 3 have been successfully isolated, whereas 3 and 4 had to be mechanically separated. The recrystallization of 3 in pentanol yielded single crystals of compound [Cu(Pip)2(Isn)2]·C5H11OH (3a). The X-ray crystal structure of 2, 3a, and 4 has been elucidated showing a cocrystal, a monomer, and an unusual coordination polymer, respectively. The Pip ligand exhibited a chelate (3a) or a monodentate (4) coordination mode, but the Isonicotinamide (Isn) ligand is the one that promoted the arrangement of different structures and also mainly directs the formation of the 2D and 3D supramolecular assemblies. All the structures have been analyzed by Hirshfeld surface. In addition, the energy frameworks and lattice energy values of 2 and 3a have been calculated.

Solvent dependent formation of Cu(II) complexes based on isonicotinamide ligand

Five solvent-dependent Cu(II) compounds have been synthesized with [Cu(μ-OAc)(μ-Pip)(MeOH)]2 (OAc = acetate; Pip = 1,3-benzodioxolecarboxylate) and isonicotinamide (Isn) as an auxiliary ligand in different solvents. In all the compounds, Pip units are displaced resulting in dimeric [Cu(μ-OAc)(OAc)(Isn)2(solvent)]2 (solvent = MeOH (2a), dmf and H2O (3) or H2O and HPip (4a)), paddle-wheel [Cu(μ-OAc)2(Isn)]2·2dmso (5) or monomeric compounds [Cu(OAc)2(HOAc)(Isn)2]·HOAc (6). All of them have been characterized by analytical and ATR-FTIR techniques and their X-ray crystal structures solved. The OAc anions construct different arrays and exhibit different coordination modes depending on the solvent used. The supramolecular expansion is constantly determined by the amide-amide pattern and the role of the occluded solvent molecules. This tendency is confirmed by Hirshfeld Surface analysis. Finally, the thermal stability of compound 4a has been analyzed.

Werner clathrates with enhanced hydrogen bonding functionality

The role of hydrogen bonding to generate molecular frameworks for selective enclathration of selected, closely related alcohols, carbonyls and water by three Ni(II) isothiocyanate based Werner hosts was scrutinized and their generation of crystal structures elucidated.Structures of host:guest compounds of H1, Ni(NCS)2(nicotinamide)4, with five alcohols were compared with five guests with carbonyl functionalities. In both cases, host columns formed by interaction via hydrogen bonded amide tetramers. However, the hydrogen bond between the guest alcohol functional group and thiocyanato sulphur showed a more robust structure than those with intercalated carbonyl guests found in layers between sheets of host molecular bands. A predictable framework of H1 host led to architectures with analogous patterns. Physical properties differed according to their hydrogen bonding capabilities. Selectivity was achieved for the separation of a pair of alcohols (1-butanol and 2-pentanol) and a pair of carbonyls (3- and 4-methylcyclohexanone), both difficult to separate due to similar physical properties. The positive discrimination characteristics of host H1 towards one of a pair of alcohols and carbonyl isomers have given possibilities for future industrial prospects.Host H2, Ni(NCS)2(isonicotinamide)4, presented three different tubulate packing arrangements, with the guests (H2O, ethanol and self-included ligand isonicotinamide) occupying channels in the structure. Hydrogen bonding between host carbonyl oxygens and amides formed molecular frameworks into which the guest was included.Mixed-ligand host H3, Ni(NCS)2(nicotinamide)2(isonicotinamide)2 with inclusion of water and methanol, confirmed our findings of hydrogen bonded frameworks with the two different ligands in H1 and H2; nicotinamide ligands formed amide tetramers, whereas the isonicotinamide ligands formed a variety of discrete hydrogen bonds with neighbouring molecules.The host networks formed porous materials for inclusion, giving the advantage of ‘tunability’, and pores with different size and nature available to accommodate guest molecules and to separate isomers.

Crystal structure and Hirshfeld surface analysis of di-aqua-bis-(isonicotinamide-κN)bis-(2,4,6-tri-methyl-benzoato-κO1)nickel(II) dihydrate.

In the title NiII complex, [Ni(C10H11O2)2(C6H6N2O)2(H2O)2]·2H2O, the divalent Ni ion occupies a crystallographically imposed centre of symmetry and is coordinated by two O atoms from the carboxyl-ate groups of two 2,4,6-tri-methyl-benzoate (TMB) ligands [Ni-O = 2.0438 (12) Å], two N atoms from the pyridyl groups of two isonicotinamide (INA) ligands [Ni-N = 2.1506 (15) Å] and two water mol-ecules [Ni-O = 2.0438 (12) Å] in a slightly distorted octa-hedral geometry. The coordinating water mol-ecules are hydrogen bonded to the non-coordinating carboxyl-ate O atom of the TMB ligand [O⋯O = 2.593 (3) Å], enclosing an S(6) hydrogen-bonding motif. Two solvent water mol-ecules are also present in the formula unit. In the crystal, a network of inter-molecular N-H⋯O and O-H⋯O hydrogen bonds link the complexes into a three-dimensional array. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H⋯H (59.8%), O⋯H/H⋯O (20.2%) and C⋯H/H⋯C (13.7%) inter-actions.

Crystal structure of aqua-tris-(isonicotinamide-κN)bis-(thio-cyanato-κN)cobalt(II) 2.5-hydrate.

The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)3(H2O)]·2.5H2O, comprises one CoII cation, three isonicotinamide ligands, two thio-cyanate anions, one aqua ligand and two water solvent mol-ecules in general positions, as well as one water solvent mol-ecule that is located on a twofold rotation axis. The CoII cations are octa-hedrally coordinated by two terminally N-bonded thio-cyanate anions, one water mol-ecule and three isonicotinamide ligands, each coordinating via the pyridine N atom. The discrete complexes are linked by inter-molecular O-H⋯O, N-H⋯O and N-H⋯S hydrogen bonding into a three-dimensional network that contains cavities in which the solvent water mol-ecules are located. The latter are linked by further O-H⋯O hydrogen bonds to the network. There are additional short contacts present in the crystal, indicative of weak C-H⋯S, C-H⋯O and C-H⋯N inter-actions.

Synthesis, crystal structure and EPR studies of vanadyl doped [Co(2-nbH)2(ina)2(H2O)] complex

A novel aquabis(isonicotinamide-κN1)bis(2-nitrobenzoato-κ2O,O′;κO)cobalt(II), (hereafter [Co(2-nbH)2(ina)2(H2O)]; 2-nbH: 2-nitrobenzoic acid; ina: isonicotinamide), complex was synthesized and characterized by using various techniques. The crystal structure was determined by X-ray diffraction (XRD) method. The magnetic properties of VO2+ doped [Co(2-nbH)2(ina)2(H2O)] complex were obtained by electron paramagnetic resonance (EPR) technique. The angular variation of EPR spectra shows that two different VO2+ complexes are present in the lattice. The FT-IR spectra of this compound were discussed in relation to other compounds containing 2-nitrobenzoato or isonicotinamide ligands. Thermal stability and reactivity of this complex were also studied by thermal analysis methods (TG/DTG/DTA).

Crystal structure of tetra-kis-(isonicotinamide-κN)bis-(thio-cyanato-κN)cobalt(II)-isonicotinamide-ethanol (1/2/1).

The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)4]·2C6H6N2O·C2H5OH, comprises one Co(II) cation, two thio-cyanate anions, four coordinating and two solvent isonicotinamide molecules and one ethanol solvent mol-ecule. The Co(II) cations are octa-hedrally coordinated by four N-coordinating isonicotinamide ligands and two terminally N-bonded thio-cyanate anions. These discrete complexes are linked by inter-molecular N-H⋯O and N-H⋯S hydrogen-bonding inter-actions into a three-dimensional network. The two isonicotinamide and the ethanol solvent mol-ecules are embedded in channels of this network and are linked through further N-H⋯O and N-H⋯N hydrogen bonds to the network. The ethanol solvent mol-ecule is disordered over two sets of sites (occupancy ratio 0.6:0.4).

Crystal structure of bis-(isonicotinamide-κN (1))bis-(thio-cyanato-κN)zinc.

The asymmetric unit of the title complex, [Zn(SCN)2(C6H6N2O)2], consists of one Zn(2+) cation located on a twofold rotation axis, as well as of one thio-cyanate anion and one neutral isonicotinamide ligand, both occupying general positions. The Zn(2+) cation is tetra-hedrally coordinated into a discrete complex by the N atoms of two symmetry-related thio-cyanate anions and by the pyridine N atoms of two isonicotinamide ligands. The complexes are linked by inter-molecular C-H⋯O and N-H⋯O, and weak inter-molecular N-H⋯S hydrogen-bonding inter-actions into a three-dimensional network.

Synthesis, crystal structure, and spectroscopic and thermal properties of the polymeric compound catena-poly[[bis(2,4-dichlorobenzoato)zinc(II)]-μ-isonicotinamide

Zinc(II) carboxylates with O-, S- and N-donor ligands are interesting for their structural features, as well as for their antibacterial and antifungal activities. The one-dimensional zinc(II) coordination complex catena-poly[[bis(2,4-dichlorobenzoato-κO)zinc(II)]-μ-isonicotinamide-κ(2)N(1):O], [Zn(C7H3Cl2O2)2(C6H6N2O)]n, has been prepared and characterized by IR spectroscopy, single-crystal X-ray analysis and thermal analysis. The tetrahedral ZnO3N coordination about the Zn(II) cation is built up by the N atom of the pyridine ring, an O atom of the carbonyl group of the isonicotinamide ligand and two O atoms of two dichlorobenzoate ligands. Isonicotinamide serves as a bridge between tetrahedra, with a Zn···Zn distance of 8.8161 (7) Å. Additionally, π-π interactions between the planar benzene rings contribute to the stabilization of the extended structure. The structure is also stabilized by intermolecular hydrogen bonds between the amino and carboxylate groups of the ligands, forming a two-dimensional network. During thermal decomposition of the complex, isonicotinamide, dichlorobenzene and carbon dioxide were evolved. The final solid product of the thermal decomposition heated up to 1173 K was metallic zinc.

Structure and magnetism of novel dinuclear cobalt(II) complexes

Two dinuclear cobalt(II) complexes of the formula [Co2X4(isonia)4] have been synthesized and structurally characterized; isonia is unidentate neutral iso-nicotinamide and X are furan-3- or furan-2-carboxylate ligands. The chromophore {CoO4N2} is formed of two iso-nicotinamide ligands and three furancarboxylate ligands where two of them bear a bridging function and one is a terminal-bidentate ligand. The magnetic data confirm a weak exchange interaction (J/hc=−2cm−1) and a high single-ion zero-field splitting (D/hc=63 and 33cm−1, respectively).

One-dimensional bimetallic cyano complexes with nicotinamide and isonicotinamide ligands

Two new 1D bimetallic Cu(II)/Ni(II) coordination polymers, {[Cu(NH3)4(μ-na)][Ni(CN)4]}n (1) and {[Cu(NH3)2(ina)2Ni(μ-CN)2(CN)2]}n (2) (na: nicotinamide, ina: isonicotinamide) have been synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, elemental, thermal analyses, and single crystal X-ray diffraction techniques. In both of the complexes, Ni(II) ion is four coordinate with four cyanide–carbon atoms in a square-planar geometry. In 1, the [Ni(CN)4]2− ion acts as a counter-ion, whereas it coordinated to the Cu(II) ions as a bridging ligand in 2. In 1 and 2, each Cu(II) ion is coordinated in a distorted octahedral geometry. Single crystal X-ray analysis showed that 1 and 2 exhibit one-dimensional linear chain running along the crystallographic a-axis and b-axis direction, respectively. Adjacent chains are further stacked through intermolecular hydrogen bonding, NH⋯π, CH⋯Ni and Ni⋯π interactions to form 3D supramolecular network.

Bis(μ-4-formylbenzoato-κ2O:O′)bis[(4-formylbenzoato-κ2O,O′)bis(isonicotinamide-κN1)copper(II)

The asymmetric unit of the centrosymmetric dinuclear title compound, [Cu2(C8H5O3)4(C6H6N2O)4], contains one half of the complex mol­ecule. The CuII atoms are bridged by the carboxyl­ate groups of two 4-formyl­benzoate (FOB) anions. Besides the two bridging FOB anions, one additional chelating FOB anion and two isonicotinamide (INA) ligands complete the distorted CuN2O4 octa­hedral coordination of each Cu2+ cation. Within the asymmetric unit, the benzene and pyridine rings are oriented at dihedral angles of 25.1 (3) and 12.6 (3)°, respectively. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network. π–π contacts between the pyridine rings [shortest centroid–centroid distance = 3.821 (3) Å] may further stabilize the crystal structure. One of the formyl groups of the two FOB anions is disordered over two sets of sites with an occupancy ratio of 0.65:0.35.

Trans-Tetraaquabis(isonicotinamide-κN1)zinc bis(3-hydroxybenzoate) tetrahydrate

The asymmetric unit of the title compound, [Zn(C6H6N2O)2(H2O)4](C7H5O3)2·4H2O, contains half of the complex cation with the ZnII ion located on an inversion center, a 3-hy­droxy­benzoate counter-anion and two uncoordinating water mol­ecules. Four water O atoms in the equatorial plane around the ZnII ion [Zn—O = 2.089 (2) and 2.128 (2) Å] form a slightly distorted square-planar arrangement and the distorted octa­hedral geometry is completed by the two N atoms [Zn—N = 2.117 (2) Å] from two isonicotinamide ligands. In the anion, the carboxyl­ate group is twisted from the attached benzene ring at 9.0 (2)°. In the crystal, a three-dimensional hydrogen-bonding network, formed by classical O—H⋯O and N—H⋯O and weak C—H⋯O hydrogen bonds, consolidates the crystal packing, which exhibits π–π stacking between the benzene and pyridine rings, with centroid–centroid distances of 3.458 (2) and 3.609 (2) Å. One of the two H atoms of each uncoordinating water mol­ecule is disordered over two orientations with an occupancy ratio of 0.60:0.40.