Month: October 2022

Category: pyridine-derivativesIn 2021 ,《Synthesis and application of self-healing elastomers with high healing efficiency and mechical properties based on multi-healing systems》 appeared in European Polymer Journal. The author of the article were Zhou, Xing; Wang, Hao; Li, Shaonan; Liu, Mengyue. The article conveys some information:

Intrinsic self-healing materials designed by combining reversible valence bonds or ionic coordination have attracted much attention due to their ability to recover from mech. damage. However, their mech. properties tend to deteriorate due to the increased rigidity of the chain. In this work, we report a self-healing polyurethane elastomer with multiple healing systems. 3,3′-dithiodipropionic acid (TDPA) and iron ion-2,6-diaminopyridine (DAP) were used as dynamic chain extenders and ionic ligands, resp. They can be effectively unsealed at a certain temperature to ensure that the self-healing efficiency is not affected by the material formula. By changing the content of hard and soft segments, the mech. properties and self-healing properties of the material can be adjusted in a large range. When the molar ratio of TDPA and DAP is 0.5:0.5, the polyurethane based on multiple healing system only needs to be healed at 70 °C for 12 h, and the self-healing efficiency can reach 93.48%. The structural rigidity and high reversibility of metal complexing agent DAP and iron ions play an important role in enhancing mech. strength and maintaining self-healing efficiency at 70 °C. Based on the above research, we prepared the strain sensor by combining self-healing polyurethane and conductive graphene. The sensor can respond to external force quickly and stably. This work provides a feasible strategy for the preparation of mech. robust polyurethane elastomers and self-healing flexible stress sensors with high self-healing efficiency at 70 °C. In the experiment, the researchers used 2,6-Diaminopyridine(cas: 141-86-6Category: pyridine-derivatives)

2,6-Diaminopyridine(cas: 141-86-6) belongs to pyridine. Pyridine and its simple derivatives are stable and relatively unreactive liquids, with strong penetrating odours that are unpleasant.Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Application In Synthesis of Bis(pyridin-2-ylmethyl)amineIn 2020 ,《A cyclometalated trinuclear Ir(III)/Pt(II) complex as a luminescent probe for histidine-rich proteins》 appeared in Dalton Transactions. The author of the article were Sarkar, Ankita; Kumar, Ravi; Das, Bishnu; Ray, Partho Sarothi; Gupta, Parna. The article conveys some information:

Organometallic complexes have important application in the field of protein staining, with potential for use in proteomic anal. The rational synthesis of a trinuclear luminescent organometallic complex with two platinum(II) centers appended to the cyclometalated ligand of the iridium(III) center is reported here. Two di-2-picolylamine groups bonded to the cyclometalated Ph pyridine moiety provide three coordinating sites to each platinum center. The replacement of chloride in the fourth coordination site of two square planar platinum metal centers with the imidazole nitrogen or sulfur atom of histidine/cysteine is evident from the change in luminescence intensity upon binding these amino acids. The increase in luminescence emission intensity upon binding of histidine to the organometallic complex allowed it to be used as a protein staining agent. Reversibility of staining upon washing with imidazole enhances the possibility of its application in mass spectrometric anal. The experimental process involved the reaction of Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0Application In Synthesis of Bis(pyridin-2-ylmethyl)amine)

Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0) is a secondary amine with two picolyl substituents. The compound is a tridentate ligand in coordination chemistry and commonly used to produce Zn-based chemosensors/probes, such as Zinpry.Application In Synthesis of Bis(pyridin-2-ylmethyl)amine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Synthetic Route of C5H3Br2NIn 2021 ,《Electronic and geometric structure effects on one-electron oxidation of first-row transition metals in the same ligand framework》 appeared in Dalton Transactions. The author of the article were Boniolo, Manuel; Chernev, Petko; Cheah, Mun Hon; Heizmann, Philipp A.; Huang, Ping; Shylin, Sergii I.; Salhi, Nessima; Hossain, Kamal Md; Gupta, Arvind K.; Messinger, Johannes; Thapper, Anders; Lundberg, Marcus. The article conveys some information:

Developing new transition metal catalysts requires understanding of how both metal and ligand properties determine reactivity. Since metal complexes bearing ligands of the Py5 family (2,6-bis-[(2-pyridyl)methyl]pyridine) were employed in many fields in the past 20 years, authors set out here to understand their redox properties by studying a series of base metal ions (M = Mn, Fe, Co, and Ni) within the Py5OH (pyridine-2,6-diylbis[di-(pyridin-2-yl)methanol]) variant. Both reduced (MII) and the one-electron oxidized (MIII) species were carefully characterized using a combination of x-ray crystallog., x-ray absorption spectroscopy, cyclic voltammetry, and d.-functional theory calculations The observed metal-ligand interactions and electrochem. properties do not always follow consistent trends along the periodic table. this observation cannot be explained by only considering orbital and geometric relaxation, and spin multiplicity changes needed to be included into the DFT calculations to reproduce and understand these trends. In addition, exchange reactions of the sixth ligand coordinated to the metal, were analyzed. Finally, by including published data of the extensively characterized Py5OMe (pyridine-2,6-diylbis[di-(pyridin-2-yl)methoxymethane])complexes, the special characteristics of the less common Py5OH ligand were extracted This comparison highlights the non-innocent effect of the distal OH functionalization on the geometry, and consequently on the electronic structure of the metal complexes. Together, this gives a complete anal. of metal and ligand degrees of freedom for these base metal complexes, while also providing general insights into how to control electrochem. processes of transition metal complexes. The experimental part of the paper was very detailed, including the reaction process of 2,6-Dibromopyridine(cas: 626-05-1Synthetic Route of C5H3Br2N)

2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. The basicity and metallophilic high donor number of these π-deficient systems has long favored them as ligands in metal catalysis. The last decade saw pyridine assume a stronger role as functional group for directed C–H oxidation/activation.Synthetic Route of C5H3Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Name: 4-CyanopyridineIn 2019 ,《The reductive C3 functionalization of pyridinium and quinolinium salts through iridium-catalysed interrupted transfer hydrogenation》 appeared in Nature Chemistry. The author of the article were Grozavu, Alexandru; Hepburn, Hamish B.; Smith, Philip J.; Potukuchi, Harish K.; Lindsay-Scott, Peter J.; Donohoe, Timothy J.. The article conveys some information:

Aromatic rings are ubiquitous in organic chem. and form the basis of many com. products. Despite the numerous routes available for the preparation of aromatic compounds, there remain few methods that allow their conversion into synthetically useful partially saturated derivatives and even fewer that allow new C-C bonds to be formed at the same time. Here we set out to address this problem and uncover a unique catalytic partial reduction reaction that forms partially saturated azaheterocycles from aromatic precursors. In this reaction, methanol and formaldehyde are used for the reductive functionalization of pyridines and quinolines using catalytic iridium; thus, inexpensive and renewable feedstocks are utilized in the formation of complex N-heterocycles. By harnessing the formation of a nucleophilic enamine intermediate, the C-C bond-forming process reverses the normal pattern of reactivity and allows access to the C3 position of the arene. Mechanistic investigations using D-labeling experiments reveal the source of hydride added to the ring and show the reversible nature of the iridium-hydride addition4-Cyanopyridine(cas: 100-48-1Name: 4-Cyanopyridine) was used in this study.

4-Cyanopyridine(cas: 100-48-1) belongs to pyridine. The basicity and metallophilic high donor number of these π-deficient systems has long favored them as ligands in metal catalysis. The last decade saw pyridine assume a stronger role as functional group for directed C–H oxidation/activation.Name: 4-Cyanopyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Safety of 2-BromonicotinaldehydeIn 2019 ,《Ligand Structure Effects on Molecular Assembly and Magnetic Properties of Copper(II) Complexes with 3-Pyridyl-Substituted Nitronyl Nitroxide Derivatives》 appeared in ACS Omega. The author of the article were Sherstobitova, Tatiana; Maryunina, Kseniya; Tolstikov, Svyatoslav; Letyagin, Gleb; Romanenko, Galina; Nishihara, Sadafumi; Inoue, Katsuya. The article conveys some information:

Reaction of Cu(hfac)2 with methyl- and bromo-3-pyridyl-substituted nitronyl nitroxides (LR) leads to assemble a diverse set of coordination complexes: mononuclear [Cu(hfac)2L2-Me], binuclear [{Cu(hfac)2}2(H2O)L2-Me], trinuclear [{Cu(hfac)2}3(L6-Br)2], pentanuclear [{Cu(hfac)2}5(L2-Me)2], and [{Cu(hfac)2}5(L2-Me)4], cocrystals [Cu(hfac)2(L2-Br)2]·[Cu(hfac)2(H2O)2] and [Cu(hfac)2(L2-Br)2]·2[Cu(hfac)2H2O], one-dimensional polymers [Cu(hfac)2L2-Br]n and [Cu(hfac)2L6-Br]n, and cyclic dimers [Cu(hfac)2L5-Me]2, [Cu(hfac)2L5-Br]2, and [Cu(hfac)2L6-Me]2. The mol. structures of the obtained complexes are strongly affected by the substituent type and its location in the pyridine heterocycle. Occupation of the second position of the pyridine ring increases the steric hindrance of both imine and nitroxide coordination sites of L2-R, which is favorable for the formation of various conformers and precipitation of complexes with different mol. structures. The pentanuclear [{Cu(hfac)2}5(L2-Me)2] and [{Cu(hfac)2}5(L2-Me)4] complexes do not have prior analogs and are valuable model objects for investigation of the mechanism of formation of various coordination polymers. The arrangement of long Cu-ONO bonds in {CuO6} square bipyramids due to the weakening nitroxide donor site in complexes, based on L2-Me, L2-Br, and L6-Br ligands, results in ferromagnetic exchange interactions between spins of Cu2+ ions and nitroxides. Complexes with substituents that do not considerably affect the coordination ability of ligands (L5-Me, L5-Br, and L6-Me) exhibit strong antiferromagnetic exchange interactions between spins of Cu2+ ions and nitroxides. The experimental part of the paper was very detailed, including the reaction process of 2-Bromonicotinaldehyde(cas: 128071-75-0Safety of 2-Bromonicotinaldehyde)

2-Bromonicotinaldehyde(cas: 128071-75-0) belongs to pyridine. Pyridine and pyridine-derived structures are privileged pharmacophores in medicinal chemistry and an essential functionality for organic chemists. As the prototypical π-deficient heterocycle, pyridine illustrates distinctive chemistry as both substrate and reagent. Safety of 2-Bromonicotinaldehyde

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Related Products of 1122-54-9In 2022 ,《Preparation of chiral aryl alcohols: a controllable enzymatic strategy via light-driven NAD(P)H regeneration》 appeared in New Journal of Chemistry. The author of the article were Xing, Xiu; Liu, Yan; Shi, Ming-Liang; Li, Kun; Fan, Xin-Yue; Wu, Zhong-Liu; Wang, Na; Yu, Xiao-Qi. The article conveys some information:

Controllable and mild photoenzymic production of chiral alcs. RCH(OH)R1 [R = Ph, 4-pyridyl, 2-naphthyl, etc.; R1 = H, Me, CH2CO2Me, etc.] was realized by coupling a versatile photochem. NAD(P)H regeneration system with (R)- or (S)-selective ketoreductases. The efficiency of NAD(P)H regeneration was improved using a rhodium functionalized metal organic framework, namely Rh-UiO-67, to adjust and control electron transport and electron utilization. Furthermore, six different ketoreductases could be successfully immobilized on Rh-UiO-67 and combined with the light-driven NAD(P)H regeneration system to produce chiral aryl alcs. Various chiral alcs. with complementary (R)- and (S)-conformations could be constructed by this method with high yields (97%) and excellent stereoselectivity (>99% ee). The results came from multiple reactions, including the reaction of 4-Acetylpyridine(cas: 1122-54-9Related Products of 1122-54-9)

4-Acetylpyridine(cas: 1122-54-9) belongs to pyridine. Pyridine and pyridine-derived structures are privileged pharmacophores in medicinal chemistry and an essential functionality for organic chemists. As the prototypical π-deficient heterocycle, pyridine illustrates distinctive chemistry as both substrate and reagent. Related Products of 1122-54-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Formula: C6H5NO2In 2021 ,《Mechanistic investigation of the aerobic oxidation of 2-pyridylacetate coordinated to a Ru(II) polypyridyl complex》 was published in Dalton Transactions. The article was written by Sousa, Sinval F.; Ertem, Mehmed Z.; Faustino, Leandro A.; Machado, Antonio Eduardo. H.; Concepcion, Javier J.; Maia, Pedro I. S.; Patrocinio, Antonio Otavio T.. The article contains the following contents:

A new ruthenium polypyridyl complex, [Ru(bpy)2(acpy)]+ (acpy = 2-pyridylacetate, bpy = 2,2′-bipyridine), was synthesized and fully characterized. Distinct from the previously reported analog, [Ru(bpy)2(pic)]+ (pic = 2-pyridylcarboxylate), the new complex is unstable under aerobic conditions and undergoes oxidation to yield the corresponding α-keto-2-pyridyl-acetate (acpyoxi) coordinated to the RuII center. The reaction is one of the few examples of C-H activation at mild conditions using O2 as the primary oxidant and can provide mechanistic insights with important implications for catalysis. Theor. and exptl. investigations of this aerobic oxidative transformation indicate that it takes place in two steps, first producing the α-hydroxo-2-pyridyl-acetate analog and then the final product. The observed rate constant for the first oxidation was in the order of 10-2 h-1. The reaction is hindered in the presence of coordinating solvents indicating the role of the metal center in the process. Theor. calculations at the M06-L level of theory were performed for multiple reaction pathways in order to gain insights into the most probable mechanism. Authors results indicate that O2 binding to [Ru(bpy)2(acpy)]+ is favored by the relative instability of the six-ring chelate formed by the acpy ligand and the resulting RuIII-OO ̇- superoxo is stabilized by the carboxylate group in the coordination sphere. C-H activation by this species involves high activation free energies (ΔG‡ = 41.1 kcal mol-1), thus the formation of a diruthenium μ-peroxo intermediate, [(RuIII(bpy)2(O-acpy))2O2]2+ via interaction of a second [Ru(bpy)2(acpy)]+ was examined as an alternative pathway. The dimer yields two RuIV:O centers with a low ΔG‡ of 2.3 kcal mol-1. The resulting RuIV:O species can activate C-H bonds in acpy (ΔG‡ = 23.1 kcal mol-1) to produce the coordinated α-hydroxo-2-pyridylacetate. Further oxidation of this intermediate leads to the α-keto-2-pyridyl-acetate product. The findings provide new insights into the mechanism of C-H activation catalyzed by transition-metal complexes using O2 as the sole oxygen source. In the experimental materials used by the author, we found Picolinic acid(cas: 98-98-6Formula: C6H5NO2)

Picolinic acid(cas: 98-98-6) is used as a chelate for alkaline earth metals. Used to prepare picolinato ligated transition metal complexes. In synthetic organic chemistry, has been used as a substrate in the Mitsunobu reaction and in the Hammick reaction.Formula: C6H5NO2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Electric Literature of C5H3Br2NIn 2020 ,《Controlling Singlet Fission with Coordination Chemistry-Induced Assembly of Dipyridyl Pyrrole Bipentacenes》 was published in ACS Central Science. The article was written by Ribson, Ryan D.; Choi, Gyeongshin; Hadt, Ryan G.; Agapie, Theodor. The article contains the following contents:

Singlet fission has the potential to surpass current efficiency limits in next-generation photovoltaics and to find use in quantum information science. Despite the demonstration of singlet fission in various materials, there is still a great need for fundamental design principles that allow for tuning of photophys. parameters, including the rate of fission and triplet lifetimes. Here, we describe the synthesis and photophys. characterization of a novel bipentacene dipyridyl pyrrole (HDPP-Pent) and its Li- and K-coordinated derivatives HDPP-Pent undergoes singlet fission at roughly 50% efficiency (τSF = 730 ps), whereas coordination in the Li complex induces significant structural changes to generate a dimer, resulting in a 7-fold rate increase (τSF = 100 ps) and more efficient singlet fission with virtually no sacrifice in triplet lifetime. We thus illustrate novel design principles to produce favorable singlet fission properties, wherein through-space control can be achieved via coordination chem.-induced multipentacene assembly. Series of ligand-bridged bipentacenes display differential rates/yields of singlet fission as a result of distinct solution-state structures arising from the identity of the coordinated alkali metal. In the experimental materials used by the author, we found 2,6-Dibromopyridine(cas: 626-05-1Electric Literature of C5H3Br2N)

2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. Pyridines, quinolines, and isoquinolines have found a function in almost all aspects of organic chemistry. Pyridine has found use as a solvent, base, ligand, functional group, and molecular scaffold. As structural elements, these moieties are potent electron-deficient groups, metal-directing functionalities, fluorophores, and medicinally important pharmacophores. Electric Literature of C5H3Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Product Details of 626-05-1In 2021 ,《Rare Fluorescence Red-Shifted Metal-Organic Framework Sensor for Methylamine Derived from an N-Donor Ligand》 was published in Crystal Growth & Design. The article was written by Yao, Shu-Li; Xu, Hui; Zheng, Teng-Fei; Liu, Sui-Jun; Chen, Jing-Lin; Wen, He-Rui. The article contains the following contents:

A three-dimensional (3D) metal-organic framework (MOF) [Cd(bbip)(NDC)]n(JXUST-8, bbip = 2,6-bis(benzimidazol-1-yl)pyridine, and H2NDC = 2,6-naphthalenedicarboxylic acid) with 8-connected bcg topol. was solvothermally synthesized and fully characterized. The fluorescence experiments demonstrate that JXUST-8 could selectively distinguish methylamine (MA) by fluorescence red shift, and the detection limit is 0.341 ppm. It is noteworthy that red shift emission could enlarge the fluorescence signal, which is beneficial to realize sensing. In addition, JXUST-8 performs relatively good thermal stability, chem. stability, and reusability. Importantly, JXUST-8 could be considered as the first example of a bbip-based MOF as well as the second case of a fluorescence red shifted MOF sensor toward MA. In the experiment, the researchers used many compounds, for example, 2,6-Dibromopyridine(cas: 626-05-1Product Details of 626-05-1)

2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. Pyridines, quinolines, and isoquinolines have found a function in almost all aspects of organic chemistry. Pyridine has found use as a solvent, base, ligand, functional group, and molecular scaffold. As structural elements, these moieties are potent electron-deficient groups, metal-directing functionalities, fluorophores, and medicinally important pharmacophores. Product Details of 626-05-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ghiazza, Clement; Faber, Teresa; Gomez-Palomino, Alejandro; Cornella, Josep published an article on January 31 ,2022. The article was titled 《Deaminative chlorination of aminoheterocycles》, and you may find the article in Nature Chemistry.Application In Synthesis of 4-Amino-2-picoline The information in the text is summarized as follows:

Herein we present a simple methodol. that enabled the NH2 groups in aminoheterocycles to be conceived as masked modification handles. With the aid of a simple pyrylium reagent and a cheap chloride source, C(sp2)-NH2 could be converted into C(sp2)-Cl bonds. The method was characterized by its wide functional group tolerance and substrate scope, allowing the modification of different classes of heteroaromatic motifs (five- and six-membered heterocycles), bearing numerous sensitive motifs. The facile conversion of NH2 into Cl in a late-stage fashion enabled practitioners to apply Sandmeyer- and Vilsmeier-type transforms without the burden of explosive and unsafe diazonium salts, stoichiometric transition metals or highly oxidizing and unselective chlorinating agents. After reading the article, we found that the author used 4-Amino-2-picoline(cas: 18437-58-6Application In Synthesis of 4-Amino-2-picoline)

4-Amino-2-picoline(cas: 18437-58-6) belongs to anime. In organic chemistry, amines are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (NH3), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines).Application In Synthesis of 4-Amino-2-picoline

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem