Isonicotinamide Ligands Research Articles

Catena-Poly[[[diaquabis(pyridine-4-carboxamide-κN)copper(II)]-μ2-squarato-κO1:O3] dihydrate

The asymmetric unit of the title compound, {[Cu(C4O4)(C6H6N2O)2(H2O)2].2H2O}n, consists of one pyridine-4-carboxamide (isonicotinamide or ina) ligand, one-half of a squarate dianion, a coordinated aqua ligand and a solvent water molecule. Both the CuII and the squarate ions are located on inversion centers. The CuII ions are octahedrally surrounded by four O atoms of two water molecules and two squarate anions, and by two N atoms of the isonicotinamide ligands. The crystal structure contains chains of squarate-1,3-bridged CuII ions. These chains are held together by N-H...O and O-H...O intermolecular hydrogen-bond interactions, forming an extensive three-dimensional network.

One- or two-dimensional organometallic arrays containing PdIr 2(μ 3-S) 2 mixed-metal sulfido cluster units connected via the nicotinamide or isonicotinamide ligands on their Pd sites through hydrogen-bonding interactions

Mixed-metal sulfido cluster [(PdCl 2)(Cp*Ir) 2(μ 3-S) 2] (Cp*=η 5-C 5Me 5) dissolved in CH 2Cl 2 reacted with two equivalent of L (L=nicotinamide, isonicotinamide, or N-methylnicotinamide) in the presence of AgBF 4 to give the cationic clusters [(PdL 2)(Cp*Ir) 2(μ 3-S) 2][BF 4] 2. The single-crystal X-ray diffraction studies of these products have disclosed that in the solid state the PdIr 2S 2 cores are self-assembled to form one-dimensional chains through the intermolecular hydrogen-bonding between the amide groups for L=nicotinamide or two-dimensional sheets via the hydrogen-bonding between the amide groups and the BF 4 anions for L=isonicotinamide, whereas no organization of the cluster cores is observed for L= N-methylnicotinamide.

Directed assembly of dinuclear and mononuclear copper(ii)-carboxylates into infinite 1-D motifs using isonicotinamide as a high-yielding supramolecular reagent

Isonicotinamide has been employed as a supramolecular reagent in the synthesis of five Cu(II) complexes, tetrakis(μ-acetato-O,O′)bis(isonicotinamide-N)dicopper(II) acetonitrile; trans-diaquabis(2-fluorobenzoato-O)-bis(isonicotinamide-N)copper(II), bis{bis(μ2-acetato-O)-acetic acid-O-bis(isonicotinamide-N)copper(II)} bis(methanol), bis(acetato-O)-acetic acid-O-bis(isonicotinamide-N)copper(II) acetic acid, bis(2-fluorobenzoato-O)-2-fluorobenzoic acid-O-bis(isonicotinamide-N)copper(II). The crystal structure determination of these compounds demonstrate that an effective supramolecular reagent can be combined with very different (chemically and structurally) inorganic building blocks and still create a family of inorganic–organic hybrid materials that all display the same principal supramolecular motifs; infinite 1-D chains. This consistency (which can be equated with a high supramolecular synthetic ‘yield’) has been achieved in the presence of several potentially disruptive (in a structural sense) molecules, e.g. water, methanol, and acetic acid. This illustrates that flexible or unpredictable coordination chemistry does not, in itself, necessarily prevent supramolecular synthesis using a reliable supramolecular reagent, in this case the structurally bifunctional isonicotinamide ligand.

(Acetonitrile)[2,6-bis(pyrazol-1-yl)pyridine](isonicotinamide)copper(II)-tetrafluoroborate-acetonitrile (1/2/2).

Molecules of the title compound, [Cu(C(2)H(3)N)(C(11)H(9)N(5))(C(6)H(6)N(2)O)](BF(4))(2).2C(2)H(3)N, comprise (acetonitrile)[2,6-bis(pyrazol-1-yl)pyridine](isonicotinamide)copper(II) cations, tetrafluoroborate anions and lattice acetonitrile molecules. The cations have distorted square-pyramidal geometries in which the N(3)-donor, viz. 2,6-bis(pyrazol-1-yl)pyridine, and the N-donor, viz. the isonicotinamide ligand, occupy the four basal positions, with the coordinated acetonitrile N-donor atom occupying the apical position. Pairs of cations are linked by N-H.F hydrogen bonds through tetrafluoroborate anions, forming centrosymmetric dimers, which are further linked by C-H.O hydrogen bonds into two-dimensional undulating sheets, three of which interpenetrate to generate a two-dimensional network.

Two-fold interpenetration of 3-D nets assembled via three-co-ordinate silver(I) ions and amide–amide hydrogen bonds

The combination of isonicotinamide with AgBF4 or AgClO4, respectively, led to isostructural compounds [tris(isonicotinamide)silver(I) tetrafluoroborate and tris(isonicotinamide)silver(I) perchlorate], containing two 3-D interpenetrating nets of three-co-ordinate silver(I) ions linked by N–H· · ·O hydrogen bonds between adjacent isonicotinamide ligands.

Electrochemical and spectroscopic investigation of prussian blue modified electrodes containing isonicotinamide

Prussian blue modified electrodes derived from Fe[Fe(CN) 5adpy] (adpy = isonicotinamide) exhibit reversible electrochemical waves at E 1 2 = 0.45 and 1.1 V vs. she, ascribed to the Fe III/II and [Fe(CN) 5adpy] 2−/3− redox couples, respectively. Reversible electrochromic behavior is observed below 0.7 V, associated with the rise and decay of the intervalence band at 775 nm. The resonance Raman spectra of the modified electrodes are dominated by the vibrational peaks of the isonicotinamide ligand; in contrast, the SERS spectra exhibit only metal-CN vibrational peaks, suggesting an adsorption mechanism involving the cyanide ligands. The electrodes based on the Ni x [Fe(CN) 5adpy] y analogue exhibit reversible waves at 0.5 and 0.7 V, ascribed to [Fe(CN) 5adpy] 3− species located in non-equivalent sites. These sites exhibit a contrasting response for K + and Na + ions.