Pyrazine Groups Research Articles

Synthesis of a New Interpenetrated Mixed Ligand Ni(II) Metal–Organic Framework: Structural, Thermal and Fluorescence Studies and its Thermal Decomposition to NiO Nanoparticles

Reaction of terephthalic acid and pyrazine with nickel nitrate under hydrothermal conditions forms a 3D metal–organic framework with the composition of [Ni(μ3 − tp)(μ2 − pyz)]n (1), where H2tp = 1,4-benzenedicarboxylic acid (terephthalic acid) and pyz = pyrazine. X-ray single crystal analysis reveals that Ni(II) centers adopt a distorted octahedral geometry which are surrounded by four oxygen atoms from three tp groups and two nitrogen atoms of pyrazine molecules in equatorial and axial positions, respectively. Coordination of Ni(II) centers by terephthalate linkers in ac plane forms infinite (4, 4)-connected 2D layers, which are further joined together by pyrazine groups to form an interlocked 3D structure. Topological studies show a two-fold interpenetrated uninodal 3D network with point symbol of (412·63). The polymer shows a blue emission band at 467 nm in the solid state at room temperature. The X-ray power diffractions (PXRD) and thermal gravimetric analysis of 1 are also presented and discussed. NiO nanoparticles have been prepared via direct calcination of 1 at 600 °C, with sizes of about 35–45 nm. Nanoparticles were further characterized by IR, scanning electron microscopy equipped with energy dispersive X-ray analyses and PXRD technique.

Sensitized near-infrared luminescence of lanthanide complexes by energy transfer from rhenium(I) complexes bridged by bis(benzimidazole) and phenanthrolino-5,6:5′,6′-pyrazine ligands

A series of new rhenium-lanthanide heterobimetallic complexes bridged by bis(benzimidazole) (BiBzImH2) and 4,7-phenanthrolino-5,6:5′,6′-pyrazine (ppz) group were synthesized. The luminescent rhenium(I) complexes, [(CO)3Re(L)] having vacant diimine site, were used as ‘complex ligand’ to prepare six new heterodinuclear d–f complexes by attaching a {Ln(dik)3} fragment (Ln=Nd, Yb, or Er; dik=trifluoro theonyl acetone) at the vacant site. All prepared complexes were characterized by various spectral techniques. Upon excitation at the MLCT absorption band of Re, due to efficient energy transfer, sensitized emission occurs from lanthanide center in the near-infrared region. The lanthanide center has low-energy f–f excited states, which are capable of accepting energy from the 3MLCT excited state of the rhenium center, leading to the quenching of 3MLCT luminescence of the rhenium(I) and subsequent sensitized lanthanide(III)-based luminescence in the near-IR region. Because bis(benzimidazole) (BibzImH2) is a short bridging ligand compared to phenanthrolino-5,6:5′,6′-pyrazine (ppz), it is able to assist in faster energy transfer from rhenium(I) to Ln(III). The Nd(III) species is found to be the most effective for quenching the 3MLCT luminescence of the rhenium component because of the high density of the f–f excited states of the appropriate energy, which makes it as a more effective energy-acceptor compared to Er(III) and Yb(III) ions.

Effects of electronegative substitution on the optical and electronic properties of acenes and diazaacenes

Large acenes, particularly pentacenes, are important in organic electronics applications such as thin-film transistors. Derivatives where CH units are substituted by sp(2) nitrogen atoms are rare but of potential interest as charge-transport materials. In this article, we show that pyrazine units embedded in tetracenes and pentacenes allow for additional electronegative substituents to induce unexpected redshifts in the optical transitions of diazaacenes. The presence of the pyrazine group is critical for this effect. The decrease in transition energy in the halogenated diazaacenes is due to a disproportionate lack of stabilization of the HOMO on halogen substitution. The effect results from the unsymmetrical distribution of the HOMO, which shows decreased orbital coefficients on the ring bearing chlorine substituents. The more strongly electron-accepting cyano group is predicted to shift the transitions of diazaacenes even further to the red. Electronegative substitution impacts the electronic properties of diazaacenes to a much greater degree than expected.

A new class of organic dyes based on acenaphthopyrazine for dye-sensitized solar cells

A new class of organic dyes based on acenaphthopyrazine derivatives, containing pyrazine group as the electron acceptor and o-dicarboxyl acids as the anchoring groups were designed and synthesized for application in dye-sensitized solar cells (DSCs). These dyes have short synthesis routes and are easily adsorbed on the surface of TiO 2. Under illumination of simulated AM1.5 solar light (100 mW cm −2), a total solar energy conversion efficiency ( η) of 4.04% was obtained for the 3-(diphenylamino)acenaphtho[1,2- b] pyrazine-8,9-dicarboxylic acid ( AP-1) in the preliminary tests, in comparison with the conventional N719 dye ( η = 7.05%) under the same conditions.

Synthesis and characterization of low bandgap copolymers based on indenofluorene and thiophene derivative

AbstractA series of low band gap, highly soluble alternating conjugated copolymers, comprised of 11,11,12,12‐tetrahexylindenofluorene and thiophene derivatives (P1‐P4), were synthesized via Pd‐catalyzed Suzuki coupling reaction with very good yields. Described here are the synthesis, thermal, optical, and electrochemical properties of these new copolymers as potential new active materials for electronic and optoelectronic device applications. P1 and P2 have electron donating non‐π‐substituents with ethylenedioxy and propylenedioxy bridging the 3,3 positions of the cyclopentadithiophene groups; whereas P3 and P4 have electron withdrawing π‐substituents (carbonyl and pyrazine groups on P3 and P4, respectively). For the main absorptions in UV‐vis spectrum, P1 and P2 displayed more red absorptions in comparison with P3 and P4. Nevertheless, much suppressed quantum yields are exhibited by P3 and P4. The behaviors of P3 can be attributed to the significant charge transfer interactions between the π‐substituents and the conjugated polymer backbone that leads to a less allowed optical transition between the ground and the lowest excited state. For P4, the weak fluoresence might associate with energy transfer from indenofluorene to the low band gap thiophene‐pyrazinethiophene‐thiophene (T‐PT‐T) unit. In comparison with the corresponding polymers containing fluorene instead of indenofluorene, the use of indenofluorene exhibited mixed effects on the optical properties and improved solubility. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5044–5056, 2009

Self-Assembly of Ambivalent Organic/Inorganic Building Blocks Containing Re6 Metal Atom Cluster: Formation of a Luminescent Honeycomb, Hollow, Tubular Metal-Organic Framework

Reactions in a sealed glass tube between melted pyrazine (pyz) and a Cs(3)Re(6)Q(i)(7)Br(i)Br(a)(6).H(2)O inorganic rhenium cluster compound (Q = S, Se; "i" for inner and "a" for apical positions) containing [Re(6)Q(i)(7)Br(i)Br(a)(6)](3-) units led to the substitution of three apical bromine ligands by three pyrazine groups with the formation of 3 CsBr as a byproduct. The resulting fac-Re(6)Q(i)(7)Br(i)(pyz)(a)(3)Br(a)(3) building unit, based on a Re(6) metal atom cluster, is neutral and noncentrosymmetric and exhibits an ambivalent organic/inorganic nature owing to the opposite disposition of the three apical pyrazine groups versus the three apical bromine atoms. These compounds were characterized by single-crystal and powder X-ray diffraction, elemental and thermal analyses, and luminescence measurements. The crystal structure of fac-Re(6)Q(i)(7)Br(i)(pyz)(a)(3)Br(a)(3).xH(2)O (Q = S (1) and Se (2)) displays an original, neutral metal-organic framework based on the self-assembling of fac-Re(6)Q(i)(7)Br(i)(pyz)(a)(3)Br(a)(3) hybrid building units. The latter are held together by supramolecular interactions: pi-pi, hydrogen bonds (C-H...N, C-H...Br(a), and C-H...Br(i)), and van der Waals contacts. It gives rise to a honeycomb porous structure of parallel hollow open-ended channels wherein the water molecules are located. Their removal does not lead to the collapsing of the structural edifice. The channel walls are constituted by hydrogen atoms from pyrazine as well as apical bromine from the cluster unit. To our knowledge, the structures of 1 and 2 constitute with that of PTMTC (perchlorotriphenylmethyl functionalized by carboxylic group radicals) one of the rare examples of stable open frameworks stabilized by supramolecular interactions between neutral molecules. Moreover, 1 is the first example of luminescent Re(6) compound built up from a noncentrosymmetric Re(6)S(i)(7)Br(i) cluster core.

Comparison of Two Tetrapodal N,O Ligands: Impact of the Softness of the Heterocyclic N-Donors Pyridine and Pyrazine on the Selectivity for Am(III) over Eu(III)

To quantify the impact of the N-donor softness on the coordination of f elements in aqueous solution, and in particular on the selectivity for Am(III) over Eu(III), we have designed the two tetrapodal hexadentate ligands N,N-bis(2-pyridylmethyl)ethylenediamine-N',N'-diacetic acid (Lpy) and N,N-bis(2-pyrazylmethyl)ethylenediamine-N',N'-diacetic acid (Lpz). These ligands bear two hard acetate groups to provide stability to the An(III) and Ln(III) complexes and two N-heterocyclic soft groups to provide Am(III) versus Eu(III) selectivity. They only differ in their N-donor moieties, pyridine or pyrazine. The proton NMR and potentiometric analyses performed on the lanthanide complexes of the two ligands indicate that a unique metallic complex, LnL, is formed and that LnLpy+ and LnLpz+ have the same structure in water. Furthermore, the hydration numbers of the europium and terbium ions in these complexes, measured by luminescence decay, have the same value (q = 3), indicating that the two ligands act as hexadentate donors in both systems. As expected, the softer pyrazine-based ligand gives less stable complexes than the pyridine-based ligand with the hard Ln(III) cations. The fragment N(CH2pz)2 containing two pyrazine functions has a very low contribution to the stability of the lanthanide complexes, even though the pyrazine groups are coordinated to the cation in water. The stabilities of the americium(III) complexes were determined by potentiometry and are greater than those found for the isoelectronic europium complexes. The selectivity for Am(III) over Eu(III) increases from 60 to 500 when the pyridine-containing fragment N(CH2py)2 is substituted by the pyrazine-containing fragment N(CH2pz)2, which demonstrates that the selectivity for Am(III) over Eu(III) is significantly enhanced when the softness of the N-heterocycle increases from pyridine to pyrazine. These new hydrophilic ligands present attractive selectivities for Am(III) over Eu(III) that could make them good candidates for the selective back extraction of Am(III) from organic solutions containing 4f and 5f elements.

Tetrapyridine and Tetrapyrazine TTF Derivatives: Synthesis, Characterization and Preparation of a Bimetallic CoII Complex

AbstractThe tetra‐substituted TTF‐type donors 4,4′,5,5′‐tetrakis(2‐pyridylethylsulfanyl)tetrathiafulvalene (1) and 4,4′,5,5′‐tetrakis(2‐pyrazylethylsulfanyl)tetrathiafulvalene (2) were prepared and characterized. These donors show a redox behaviour that is comparable with similar unsubstituted TTF donors, with a small increase of the redox potentials due to the electron‐withdrawing effect of the pyridine and pyrazine groups. Single crystal X‐ray diffraction analyses show structures with a strong segregation of TTF and azo moieties. The pyridine‐substituted donor 1 was used as a bridging ligand to prepare a dinuclear CoII‐coordination complex [1Co2(hfac)4] (hfac = hexafluoroacetylacetonate) with redox properties identical to that of 1. This dinuclear complex presents an effective magnetic moment of ca. 8 μB, corresponding to nearly independent S = 3/2 spins with weak antiferromagnetic interactions below 65 K. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Synthesis and Structural Investigation of New Triptycene-Based Ligands: En Route to Shape-Persistent Dendrimers and Macrocycles with Large Free Volume

Triptycene was used to build a series of ligands containing pyrazine groups for use in forming coordination frameworks and as model compounds toward target shape-persistent dendrimers and macrocycles. The phenylenediamine precursors are formed by controlled double nitration/reduction of triptycene, followed by condensation with triptycenyl o-quinone to form the ligands. Solid-state structures show that the ligands favor packing in layered structures with intermolecular pi stacking. Increasing the length of the wings still allows for effective packing, but increasing the number of pyrazine groups or adding more triptycenyl moieties reduces packing efficiency. To demonstrate the potential of these molecules to function as ligands, a coordination complex of 15 with copper(I) iodide was obtained and found to form dimers that pack into a layered arrangement.

Synthesis and Properties of Cobalt(III) Complexes of 4-Substituted Pyridine-Capped Dioxocyclams

Cobalt(III) acetate and cyanide complexes of a series of 5,12-dioxocyclams capped across the 1,8-position by 4-substituted pyridines or pyrazine were synthesized and fully characterized. Both the spectroscopic and structural parameters for these complexes were remarkably insensitive to the electronic nature of the capping group, which ranged from the pi-accepting pyrazine group to the sigma-donating 4-[(dimethylamino)phenyl]pyridyl group. All of the complexes underwent an irreversible, one-electron reduction [Co(III)-->Co(II)] at potentials ranging from -0.95 V vs saturated calomel electrode (SCE) for the pyrazine-capped cobalt acetate complex to -1.36 V vs SCE for the pyridine-capped cobalt cyanide complexes. Pyridine-capped cobalt(III) cyanide complex underwent reaction with Rh2(OAc)4 and ruthenium(II) phthalocyanine[bis(benzonitrile)] to form tetrametallic and trimetallic complexes through coordination bridging by the cyanide nitrogen lone pair. These complexes represent two quite different structural types for cyanide-bridged polymetallics. Complex has a relatively long (2.192 A) cyanide N-to-Rh bond, and the CN-Rh bond angle (157.6 degrees) is strongly distorted from linear. In contrast, complex has a substantially shortened cyanide N-to-Ru bond (2.017 A) and an almost linear arrangement along the entire bridging axis of the molecule.

Hydrogen-bonding complexes of functionalized BEDT-TTF derivatives with chloranilic acid

The two crystalline donor-acceptor complexes showing hydrogen-bondings between bis(ethylenedithio) tetrathiofulvalene (BEDT-TTF) derivatives containing pyridine and pyrazine groups and 2,5-dichloro-3,6-dihydroxyl-1,4-benzoquinone (chloranilic acid) were prepared. X-ray structure analyses revealed that functional groups play an important role in constructing the unique crystal structures.

Stereoisomers of palladium(II) complexes with the dipyridyl ligands 2,3-di(2-pyridyl)pyrazine (dpp), 2,3-di(2-pyridyl)quinoxaline (dpq) and 6,7-dimethyl-2,3-di(2-pyridyl)quinoxaline (ddpq). Crystal structure of [Pd(dpq) 2](PF 6) 2

A solid-state and solution study to characterize the possible configurations of the [Pd(L) 2] 2+ cations (L=dpp, dpq, ddpq) has been carried out. To accomplish this objective the homoleptic complexes [Pd(L) 2](hfac) 2 (L=dpp, dpq, ddpq; hfac=hexafluoroacetylacetonate ion) were isolated. The syntheses were performed in diethyl ether by reacting [Pd(hfac) 2] with a two molar equivalent of the respective L ligand. Besides, X-ray quality crystals were obtained by metathesis with NH 4PF 6 to derive the hexafluorophosphate species [Pd(dpq) 2](PF 6) 2. The X-ray crystallographic study shows that the coordination sphere of the [Pd(dpq) 2] 2+ cation is square planar and that the bidentate chelating dpq ligands are linked via their N-pyridine atoms. Furthermore, the cation structure reveals an intramolecular π–π stacking between the two quinoxaline rings in a ‘pincer-like’ configuration. In CDCl 3 solution, the 1H NMR spectra of the [Pd(L) 2](hfac) 2 complexes permit to infer the presence of a mixture of two isomeric forms with different populations. The results suggest that the predominant form being that of the solid-state ‘pincer-like’. For the less abundant species a configuration with the quinoxaline groups (dpq, ddpq) or pyrazine groups (dpp) in opposite side respect to the plane of the Pd(II) centre, ‘step-like’, is suggested. The preponderance of the ‘pincer-like’ configuration was attributed to the influence of the aromatic π–π stacking interactions.

Synthesis and X-ray characterization of a polymeric 1:3 complex of copper(II) nitrate with pyrazine

The structure of poly-μ-pyrazine-bis(pyrazine)(dinitrato-O)copper(II), Cu(pyz)3(NO3)2, has been investigated by X-ray diffraction. The compound crystallizes in the triclinic space group $$P\bar 1$$ with a = 6.8040 (10), b = 7.2860 (10), c = 9.289 (2) A, α = 69.65 (2), β = 68.51 (2), γ = 67.51 (2)°, and Z = 1. The structure consists of linear chains of copper ions bridged by bidentate pyrazine groups, with monodentate terminal pyrazine and nitrate groups completing the distorted octahedral geometry about the copper ions.

Second Supplements to the Second Edition of Rodd's Chemitry of Carbon Compounds. Volume IV: Heterocyclic Compounds. Part I. Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J. Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine, Phenothiazine, Phenazine and Sulphur Dyes.

ADVERTISEMENT RETURN TO ISSUEPREVBook ReviewSecond Supplements to the Second Edition of Rodd's Chemitry of Carbon Compounds. Volume IV: Heterocyclic Compounds. Part I. Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J. Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine, Phenothiazine, Phenazine and Sulphur Dyes. Six-membered Heterocyclic Compounds with Three or More Hetero-Atoms Edited by M. Sainsbury. Elsevier, Amsterdam. 2000. xiv + 299 pp. 15 × 23 cm. ISBN-0-444-82980-6. $183.50.Arnold MartinView Author Information Department of Pharmacology and Toxicology College of Pharmacy The University of Arizona Health Sciences Center Tucson, Arizona 85721-0207Cite this: J. Med. Chem. 2000, 43, 11, 2291Publication Date (Web):May 11, 2000Publication History Published online11 May 2000Published inissue 1 June 2000https://doi.org/10.1021/jm000175jCopyright © 2000 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views148Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (22 KB) Get e-AlertsSUBJECTS:Dyes and pigments,Heterocyclic compounds,Nitrogen,Oxygen,Sulfur Get e-Alerts

Second Supplements to the 2nd Edition of Rodd's Chemistry of Carbon Compounds. Rodd's Chemistry of Carbon Compounds. Volume IV. Heterocyclic Compounds. Part I: Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J: Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine,

Second Supplements to the 2nd Edition of Rodd's Chemistry of Carbon Compounds. Rodd's Chemistry of Carbon Compounds. Volume IV. Heterocyclic Compounds. Part I: Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J: Six-membered Heterocyclic Compounds with Two Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine,

Supplements to the 2nd Edition of Rodd's Chemistry of Carbon Compounds. Supplement to Volume IV. Heterocyclic Compounds. Part I. Six-Membered Heterocyclic Compounds with Two-Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J. Six-Membered Heterocyclic Compounds with Two-Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine, Phenothiazine, Phenazine and Sulphur Dyes. Six-Membered

Supplements to the 2nd Edition of Rodd's Chemistry of Carbon Compounds. Supplement to Volume IV. Heterocyclic Compounds. Part I. Six-Membered Heterocyclic Compounds with Two-Hetero-Atoms from Group V of the Periodic Table: the Pyridazine and Pyrimidine Groups. Part J. Six-Membered Heterocyclic Compounds with Two-Hetero-Atoms from Group V of the Periodic Table: the Pyrazine Group, Phenoxazine, Phenothiazine, Phenazine and Sulphur Dyes. Six-Membered

Photometabolism of Heterocyclic Aromatic Compounds by Rhodopseudomonas palustris OU 11

Rhodopseudomonas palustris OU 11 (ATCC 51186; DSM 7375) isolated from a pond of chemical industry effluent could anaerobically photometabolize heterocyclic aromatic compounds belonging to the pyridine and pyrazine groups only after a period of adaptation on pyrazinoic acid of 5 to 6 weeks. Growth on heterocyclic compounds was light dependent. The effects of various concentrations of heterocyclic compounds on growth suggest that higher concentrations of these compounds inhibit growth and are toxic.

Energetics of organic solid-state reactions: electronic structure and photoreaction mechanism of the 2,5-distyrylpyrazine oligomer molecular crystal

An investigation of the 2,5-distyrylpyrazine (DSP) oligomer crystal electronic structure is presented in order to more completely characterise the oligomer photoreaction leading to the formation of the crystal of the macromolecule. The electronic transitions observed in the oligomer crystal include an π * ←n transition at 30 250 cm -1 and a π * ←π transition at 34 000 cm -1 which are both due to the styrylpyrazine moiety in the oligomer. Higher energy transitions include those from the pyrazine groups in the oligomer backbone and the phenyl side groups. In solution these transitions occur at lower energies, indicating a change in molecular conformation of the oligomer from that in the crystal

Structure and magnetic exchange in poly-bis(pyrazine)bis(methanesulfonato-O)-copper(II). One-dimensional exchange in a two-dimensional polymer

Crystals of poly-bis(pyrazine)bis(methanesulfonato-O)copper(II) are orthorhombic, a = 8.199(1), b = 13.130(1), c = 6.913(1) Å, Z = 2, space group Pnnm. The structure was solved by conventional heavy atom methods and was refined by full-matrix least-squares procedures to R = 0.025 and Rw = 0.033 for 1226 reflections with I ≥ 3σ(I). The complex contains parallel sheets, each sheet consisting of a square array of copper(II) ions bridged by two types of bidentate pyrazine ligands. The CuN4O2 chromophore is tetragonally elongated; the equatorial plane contains two pyrazine nitrogen atoms (Cu—N(1) = 2.058(2) Å) and two oxygen atoms from monodentate methanesulfonate ligands (Cu—O(1) = 1.956(1) Å); the axial sites are occupied by bridging pyrazine groups with significantly longer Cu—N bond lengths (Cu—N(2) = 2.692(2) Å) Magnetic susceptibility studies (82 to 4.2 K) reveal antiferromagnetic behaviour with a susceptibility maximum at about 6.2 K. Exchange coupling in the complex is considered to take place primarily via the more strongly bound, equatorially coordinated pyrazine ligands. Analysis of the magnetic susceptibility data according to a Heisenberg linear chain of interacting S = 1/2 spins yields best fit values of J = −3.82 cm−1 and g = 2.13. Vibrational and electronic spectroscopic and differential scanning calorimetric studies on the title compound and, for comparison, on the related mononuclear pyridine complex, bis(methanesulfonato)-tetrakis(pyridine)copper(II), are also reported.

Phthalocyaninatoiron with Pyrazine as a Bidentate Bridging Ligand

The synthesis and properties of one-dimensional conductors are of topical interest. It has now proved possible to synthesize (1) and a polymer (2), in which PcFe and pyrazine groups alternate. The physical properties of (2) indicate extensive electron delocalization over the pyrazine bridges.