109385-79-7

Upstream product

• 4437-51-8 3,4-hexanedione 
• 18514-52-8 2,3-diaminomaleonitrile 
• 1187-42-4 diaminomaleonitrile 
• 1187-12-8 1,1-diamino-2,2-dicyanoethylene 
• 13481-25-9 pyrazine-2,3-dicarbonitrile 
• 802294-64-0 propionic acid 

Downstream Products

• 1350747-21-5 (Z)-N-(2,3-diethyl-7-phenyl-5H-pyrrolo[3,4-b]pyrazin-5-ylidene)-2,3-diethyl-7-phenyl-6H-pyrrolo[3,4-b]-pyrazin-5-amine 

Relevant academic research and scientific papers

Subphthalocyanine azaanalogues – Boron(III) subporphyrazines with fused pyrazine fragments

Сyclotrimerization of pyrazine-2,3-dicarbonitrile and its phenyl substituted derivative in the presence of BCl3 in p-xylene leads to azaanalogues of subphthalocyanine dye. Non-substituted tripyrazinosubporphyrazine [Pyz3sPABCl] was formed only in trace amounts allowing only limited spectral study in solution. Hexaphenyl substituted derivative [Ph6Pyz3sPABCl] was isolated as chlorboron(III) complex and fully characterized by 1H, 13C, 11B NMR, IR, electronic absorption and emission spectroscopy, cyclovoltammetry and its structure was established by single crystal X-ray diffraction. Pyrazine fused subporphyrazines exhibit strong absorption bands at 300–310 and 530–550 nm. The phenyl substituted derivative [Ph6Pyz3sPABCl] has an additional intense charge transfer band at 390 nm and can be reversibly reduced at ?0.81 V (vs Ag/AgCl in MeCN). The influence of pyrazine rings on the geometrical and electronic structural features and spectral properties of subporphyrazine dye was also studied using DFT and TD DFT methods. Experimental and theoretical results evidence that fusion of pyrazine rings leads to stabilization of the frontier π-molecular orbitals and endows the macrocycle with enhanced electron deficiency. Pyrazine fused subporphyrazines can be considered as perspective dyes intensively absorbing in the 300–600 nm range for applications as n-type materials in organic electronics.

Silica gel an efficient catalyst for one-pot synthesis of pyrazines from ethylenediamine and 1, 2-diketones and their analogs

A straightforward one-pot synthesis of pyrazines from ethylenediamine and 1, 2-diketones/ α-hydroxy ketone/α-bromo ketone under solvent-free conditions at room temperature is described. This environmentally benign process has the edge on previous methods in respect of workup procedure, ease and cost of reaction, and use and generation of hazardous substances. The catalyst is recovered, characterized, and proved to be recyclable for successive four runs examined with appreciable conversions.

Clean and green approach for one-pot synthesis of pyrazines from Eth-ylenediamine and 1,2-diketone or its analogues under neat reaction condition

Background: Compounds having N-heterocyclic moieties are of huge importance in the field of agrochemical, pharmaceutical, biological, fragrances, etc. Due to a lot of applications associated with pyrazine moieties, their synthesis has always been important for organic chemists. Method: Surfeit synthetic methodologies are documented in literature. Most of the methodologies used expensive solvents, harmful metal catalyst and all suffer from rigorous work-up procedures. An efficient, environmentally benign methodology, needs to be developed. We mixed ethylenediamine (2mmol) with 1, 2-diketone(1mmol), later, α-hydroxy ketone and α-bromo ketone on magnetic stirrer at room temperature under neat reaction condition for 5 to 10 hrs. Results: After purification by column chromatography using silica gel(60-120 mesh) and pet-ether, et-hylacetate mixture as eluent, we achieved pyrazine derivatives from moderate to high yield. Conclusio n: Efficient and clean procedure for one-pot preparation of pyrazines from ethylenediamine and 1, 2-diketones or with α-hydroxy ketone or with α-bromo ketone has been carried out under neat reaction condition at room temperature. Environmentally benign process furnishing moderate to excellent yields of the product and simple work-up giving pure products are special features of this reaction.

A selective colorimetric and fluorometric ammonium ion sensor based on the H-aggregation of an aza-BODIPY with fused pyrazine rings

The synthesis of a novel aza-BODIPY dye functionalized with fused pyrazine rings, suitable for use as a selective colorimetric and fluorometric sensor for NH4+, is outlined. In addition to significant fluorescence quenching, an obvio

ZnII and Hg11 complexes with 2,3-substituted-5,6- di(1H-tetrazol-5-yl)pyrazine ligands: Roles of substituting groups and synthetic conditions on the formation of complexes

In our continuing efforts to explore the effects of substituting groups of bridging ligands on the structure and properties of their complexes, two structurally related bis(tetrazolate) ligands, 2,3-diethyl-5,6-di(1H-tetrazol-5- yl)pyrazine (H2L1) and 2,3-diphenyl-5,6-di(1H-tetrazol-5- yl)pyrazine (H2L2), have been designed, and seven Zn 11 and Hg11 complexes with the two ligands, [Zn 2(L1J2(H2O)4](H 2O)4 (1), ([Zn2(L1J 2](H2O)0.5}∞ (2), [Zn 6(L2)6(H2O)12] (3), [Zn(L2]∞, (4), [Hg(L1)Br] ∞ (5), {[Hg4(L2)4(H 2O)}6](H2O)}∞ (6), and [Hg3(L2)2(H2O)0.5Br 2]∞, (7), have been synthesized and characterized. 1 has a dinuclear structure in which Zn is four-coordinated to furnish a distorted tetrahedral geometry, and in the crystal structure the dinuclear units are further assembled to form a three-dimensional (3D) framework by hydrogen bonds. 2 possesses a 3D framework with (4,122] topology in which the Zn11 center is four-coordinated by N atoms of the ligand. 3 has a hexanuclear structure comprised of two trinuclear motifs as basic building units each of which has three types of coordination environments around the Zn 11 ions, and the hexanuclear units are interlinked by O-H...N hydrogen-bonding to generate a two-dimensional (2DJ framework. 4 takes a 3D (4,8,10) topology, in which ZnII ions act as three-connected nodes and the L2 ligand takes a chelating-bridging mode being similar to that in 1.5 possesses a 2D (4,8,8) layer structure with one kind of Hg II center four-coordinated by one Br anion, two N atoms from two L1 ligands, and one weakly coordinated N atom from another L 1 ligand. 6 has two kinds of one-dimensional chain structures with two kinds of Hg ions,and one kind of these chains is further assembled into 2D sheets via hydrogen-bonding interaction. 7 has a 2D layer structure with one kind of Hg11 center coordinated by a Br anion, the other one being seven-coordinated by six N atoms from four L2 ligands and one weakly coordinated O atom from a water molecule. In this work, 1,3,5, and 6 were synthesized by the conventional method at room temperature, while 2, 4, 7 were prepared under hydrothermal conditions. These results show that the substituting groups of ligands and the reaction conditions have great influences on the formation of these complexes. In addition, the luminescent properties of complexes 1-7 have been briefly studied.

Reaction of Pyrazine-2,3-dicarbonitrile and 1,3-Dimethyllumazine with Alkyl Radicals

Pyrazine-2,3-dicarbonitrile (1) reacts with alkyl radicals to give mono- 3 and di-alkylated pyrazine-2,3-dicarbonitriles 4.Similarly 1,3-dimethyllumazine (2) reacts with alkyl radicals to give 7-alkyl-1,3-dimethyllumazines 8 as a major product.The reactivity of alkyl radicals decreases in the order tertiary, secondary, and primary, and 1 is more reactive than 2 in those radical substitution reactions.