Tag: 300-400

Jia, Meng-Ze; Cui, Jing-Wang; Rao, Cai-Hui; Chen, Yun-Rui; Yao, Xin-Rong; Zhang, Jie published an article in ACS Sustainable Chemistry & Engineering. The title of the article was 《Switchable ROS Species Regulation Facilitates the Selective Oxidation of Benzyl Alcohols Enabled by an Organic Photocatalyst》.Name: 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine The author mentioned the following in the article:

Benefiting from the regulation of ROS species through a simple and feasible strategy, an efficient and switchable photocatalytic protocol for the chemoselective synthesis of aldehydes and carboxylic acids via oxidation of primary alcs. under mild conditions was developed. Using the pyridinium derivative as a metal-free organic photocatalyst, a variety of benzyl alcs. can be converted into aldehydes or carboxylic acids under an air atm. at room temperature with high selectivity and yield via simple solvent regulation. A feasible tandem reaction combining the pyridinium-catalyzed alc.-to-aldehyde conversion and catalyst-free photoinduced oxidation of aromatic aldehydes provides a powerful and efficient approach for the one-pot oxidation of benzyl alcs. to carboxylic acids, while a small amount of water can effectively regulate the competition of electron transfer and energy transfer and inhibit the generation of carboxylic acids, facilitating highly efficient and selective oxidation of alcs. to aldehydes. In the experimental materials used by the author, we found 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Name: 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Name: 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Reference of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridineOn September 16, 2020 ,《Multichromic Monolayer Terpyridine-Based Electrochromic Materials》 was published in ACS Applied Materials & Interfaces. The article was written by Laschuk, Nadia O.; Ahmad, Rana; Ebralidze, Iraklii I.; Poisson, Jade; Easton, E. Bradley; Zenkina, Olena V.. The article contains the following contents:

The article describes novel electrochromic materials (ECMs) that are based on a monolayer consisting of two or three isostructural metal complexes of 4′-(pyridin-4-yl)-2,2′:6′,2′′-terpyridine simultaneously deposited on surface-enhanced support. The support was made by screen printing of indium tin oxide (ITO) nanoparticles on ITO-glass and has a surface area sufficient for a monolayer to give color visible to the naked eye. The ability to sep. electrochem. address the oxidation state of the metal centers on the surface (i.e., Co2+/Co3+, Os2+/Os3+, and Fe2+/Fe3+) provides an opportunity to achieve several distinct color-to-color transitions, thus opening the door for constructing monolayer-based multicolor ECMs. The results came from multiple reactions, including the reaction of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Reference of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Reference of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridineThe lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Synthetic Route of C20H14N4On June 10, 2020, Sharma, Kamna; Gupta, Sandeep K.; Murugavel, Ramaswamy published an article in European Journal of Inorganic Chemistry. The article was 《Discrete and Polymeric Cobalt Pyrophosphates Derived from Pyrophosphoric Acid Diester Ar2H2P2O7》. The article mentions the following:

While the structural elucidation and coordination chem. of organo-monophosphates have been well investigated, research on the simplest member of organo-oligophosphates, viz. diorganopyrophosphates, is relatively rare due to the inherent hydrolytic instability of the ligand. Water elimination from the 2,6-diisopropyl Ph phosphate (dippH2) by the action of dicyclohexylcarbodiimide (DCC) results in the isolation of a diorganopyrophosphates ligand formulated as [O{P(OAr)(OH)(O)}2] (1 or pyrodippH2) (Ar = 2,6-diisopropylphenyl). Due to the instability of 1, it has been transformed into its sodium salt [O{P(OAr)(ONa)(O)}2] (2), which has been used for further reactions to prepare cobalt pyrophosphate complexes 3-7. Reaction of 2 with anhydrous cobalt(II) chloride in the presence of N-heterocyclic ligands results in the formation of [Co(pyrodipp)(imz)3] (3), [Co(pyrodipp)(bpy)2](CH3OH) (4) and [Co(pyrodipp)(phen)2] (5) (imz = imidazole; bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline). Use of multidentate ancillary ligand such as 4-pyridyl-2,2′:6′,2”-terpyridine (pyterpy) under similar reaction conditions leads to the formation of a one-dimensional zig-zag cobalt pyrophosphate coordination polymer [Co(pyrodipp)(pyterpy)(CH3OH)]n (6). In the absence of any ancillary ligand, the reaction between cobalt(II) chloride and 2 in acetonitrile results in the isolation of an interesting inorganic polymer [Co(pyrodipp)(CH3CN)2]n (7), whose backbone consists of a chain of spirocycles of CoP2O3 rings, joined at the cobalt centers. The newly synthesized cobalt pyrophosphates 3-7 have been characterized by both anal. and spectroscopic techniques, magnetic studies apart from single-crystal x-ray diffraction studies in each case. A striking and persistent structural feature in 3-7 is the presence of the cobalt pyrophosphate six-membered metallacycle Co(OPOPO). While cobalt metal exists in trigonal bipyramidal geometry in complex 3, distorted octahedral coordination geometry is observed for cobalt centers in complexes 4-7. In the experimental materials used by the author, we found 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Synthetic Route of C20H14N4)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Synthetic Route of C20H14N4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Bromination of methylpyridines in fuming sulfuric acid》 were Does, L. van der; Hertog, H. J.. And the article was published in Recueil des Travaux Chimiques des Pays-Bas in 1965. Safety of 2,3,5-Tribromo-4-methylpyridine The author mentioned the following in the article:

Methylpyridines heated and shaken with Br and H2SO4 produce a mixture of mono and polybromomethyl derivatives A tube was charged with 18.6 g. 2-picoline (I), 100 ml. fuming H2SO4 containing 65% SO3, and 12.8 Br and sealed. The contents were heated at 80° for 7 hrs. with shaking. On cooling 5-bromo-2-picoline (II) [m. 32-3°; HgCl2 adduct m. 189-91° (alc.)] sep. The residue [a mixture of II and 3-bromo-2-picoline (III)] is converted to 5-amino-2-picoline [m. 95-6° (petroleum ether)] and 3-amino-2-picoline in 84% yield. Bromination of 18.6 g. I at 130° gives 20 g. of a mixture of II and III and 3.6 g. of a residue which on steam distillation yields 0.8 g. 3,5,6-tribromo-2-picoline, m. 76-7° (alc.). No dibromopicolines were found. Bromination of 18.6 g. 3-picoline at 80° yields 5.2 g. 5-bromo-3-picoline (IV) (m. 16.5-7°), 2,4 g. 2-bromo-3-picoline, 0.4 g. 6-bromo-3-picoline, and 7.2 g. 2,5-dibromo-3-picoline (V) (m. 41-2°), separated by preparative gas liquid chromatography. IV us converted to 5-amino-3-picoline [m. 61-3° (petroleum ether); picrate m. 225° (decomposition)] in 90% yield. V is identified by comparing it with an authentic sample prepared from 2-amino-5-bromo-3-picoline [m. 90-2° (petroleum ether)] with 48% HBr in 70% yield. Bromination of 18.6 g. 4-picoline (VI) at 80° yields 17 g. 3-bromo-4-picoline (VII) [b9 74-5° nD 1.5610; HgCl2 adduct, m. 175-7° (alc.)], 3,5-dibromo-4-picoline (VIII) [m. 104-7°; HgCl2 adduct m. 219-21° (alc.)], and 0.03 g. 2,3,5-tribromo-4-picoline (IX) [m. 56-7° (aqueous alc.)]. No 2,5-dib0romo-4-picoline [m. 37-8° (alc.)] was found. Bromination of 0.15 mole VI at 90° gives 0.06 mole VIII and 0.03 mole IX. VII, heated with aqueous NH3 and CuSO4.5H2O in a sealed tube at 135° for 50 hrs., gives 3-amino-4-picoline (m. 106-7°; picrate m. 177-8°) in 85% yield. The structure of IX was proved by preparing it from 2-amino-3,5-dibromo-4-picoline [m. 123-4° (aqueous alc.)] with HBr. IX is converted to 3,5-dibromo-2-hydrazino-4-picoline (X) [m. 151-2° (alc.)] in 65-70% yield by heating with N2H4.H2O in 96° aqueous alc. at 130° for 5 hrs. in a sealed tube. X, when refluxed 4 hrs. with 10% aqueous CuSO4 solution, converts to VIII (30% yield), thus proving its structure. Bromination of 32.1 g. 2,6-lutidine (XI) at 55° for 5 hrs. produces 12 g. 3-bromo-2,6-lutidine [b14 82.5-3°, n2D0 1.5598; picrate m. 148-50° (alc.)] which can be converted to 3-amino-2,6-lutidine (m. 122°) to prove its structure. Bromination of 15.9 g. XI at 90° for 7 hrs. produces 32.8 g. crude 3,5-dibromo-2,6-lutidine (m. 46-57°) on steam distillation (m.p. of pure compound is 64°). Ionic mechanism for the bromination is postulated. The influence of Me groups in orientation is seen as less than that of the NH2 group. In the experiment, the researchers used many compounds, for example, 2,3,5-Tribromo-4-methylpyridine(cas: 3430-25-9Safety of 2,3,5-Tribromo-4-methylpyridine)

2,3,5-Tribromo-4-methylpyridine(cas: 3430-25-9) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Safety of 2,3,5-Tribromo-4-methylpyridine Pyridine has a conjugated system of six π electrons that are delocalized over the ring.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《A delocalized cobaltoviologen with seven reversibly accessible redox states and highly tunable electrochromic behaviour》 were Mansoor, Iram F.; Wozniak, Derek I.; Wu, Yilei; Lipke, Mark C.. And the article was published in Chemical Communications (Cambridge, United Kingdom) in 2020. Formula: C20H14N4 The author mentioned the following in the article:

CoII mediates electronic coupling between two N-Me-pyridinium-terpyridine ligands that are related to redox-active N,N-dialkyl-4,4′-bipyridinium dications (viologens). Borderline Class II/III electronic delocalization imparts the cobaltoviologen complex with distinct electronic properties (e.g., 7 accessible redox states) relative to those of viologens, leading to enhanced electrochromism. After reading the article, we found that the author used 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Formula: C20H14N4)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Formula: C20H14N4The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Application In Synthesis of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridineOn November 20, 2021 ,《Coordination-driven self-assembly of nanoZnO hybrids with tripodal zinc terpyridyl-viologen complex multilayers and their photochromic properties》 appeared in Colloids and Surfaces, A: Physicochemical and Engineering Aspects. The author of the article were Xian, Yu; Ma, Dong-Mei; Liu, Jian-Hong; Qian, Dong-Jin. The article conveys some information:

Viologen (VIO) functionalized nanomaterials and supramol. systems have attracted much attention because of their well reversible redox properties, unique photo-/electrochromic and radical-rich features that resulting in potential applications in the fields of coloration and memory devices, energy conversion and biomimetic chem. Here, a tripodal terpyridyl-viologen (TPyVIO) multidentate ligand was newly synthesized, which was then used as a linker, together with Zn2+ ion as a connector, to construct Zn-TPyVIO multilayers on the surfaces of nanoZnO particles to produce nanoZnO@(Zn-TPyVIO)n hybrids by a layer-by-layer (LBL) technique. Luminescent emission of nanoZnO semiconductors was largely quenched in the nanoZnO@(Zn-TPyVIO)n hybrids, attributed to a quick electron transfer from the conduction band of excited nanoZnO particles to viologens; this electron transfer process resulted in the formation of colored monovalent viologen radical cations. Reversible redox couple was recorded for the glass carbon electrode modified by the nanohybrids, with the cationic and anionic potentials at approx. – 0.78– 0.84 and – 0.63–0.73 mV (vs Hg/Hg2Cl2), resp. Finally, it was revealed that the nanoZnO@(Zn-TPyVIO)n hybrids displayed well photochromic behaviors under light radiation. The experimental part of the paper was very detailed, including the reaction process of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Application In Synthesis of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Application In Synthesis of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Vapochromic luminescent proton conductors: switchable vapochromism and proton conduction of luminescent Pt(II) complexes with proton-exchangeable sites》 were Kobayashi, Atsushi; Imada, Shin-ichiro; Shigeta, Yasuhiro; Nagao, Yuki; Yoshida, Masaki; Kato, Masako. And the article was published in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices in 2019. Formula: C20H14N4 The author mentioned the following in the article:

Two luminescent and highly proton-conductive Pt(II) complexes [PtCl(tpypy)]Cl and [PtCl(tpypyH)]Cl2 (1 and 1·HCl, resp.; tpypy = 2,2′: 6′,2”-terpyridine-4′,4”’-pyridine) were successfully synthesized. X-ray anal. revealed that the intermol. Pt···Pt interaction was ineffective in the monohydrated form of 1·H2O but effective in dihydrate and hexahydrate forms, 1·HCl·nH2O (n = 2 and 6). Yellow luminescence (λem = 519 nm and Φ = 0.016) assigned to intraligand 3π-π* phosphorescence was observed for 1·H2O, whereas a stronger red emission ascribable to the phosphorescence from the triplet metal-metal-to-ligand charge transfer (3MMLCT) state was observed for the HCl adduct 1·HCl·nH2O (λem = 741 nm, Φ = 0.06 for n = 2, λem = 642 nm, and Φ = 0.10 for n = 6). Both complexes exhibited strong relative humidity (RH)-dependent proton conductivity, while surprisingly high conductivity was observed for 1·HCl (6.8 × 10-3 S cm-1) at 95% RH at 298 K. The reversible transformation between 1 and 1·HCl was achieved upon exposure to humid HCl gas and heating and their vapochromic behavior was completely different owing to the presence of acidic N-H protons and the addnl. hydrophilic Cl- counteranions in 1·HCl. To the best of the authors’ knowledge, these complexes are the first switchable vapochromic and highly proton conductive materials that can be employed to visualize the proton conducting state by color and luminescence. The results came from multiple reactions, including the reaction of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Formula: C20H14N4)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Formula: C20H14N4The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《A color-tunable single molecule white light emitter with high luminescence efficiency and ultra-long room temperature phosphorescence》 were Ma, Xiao; Jia, Ling; Yang, Baozhu; Li, Jipeng; Huang, Wei; Wu, Dayu; Wong, Wai-Yeung. And the article was published in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices in 2021. Synthetic Route of C20H14N4 The author mentioned the following in the article:

Developing organic single mol. white light emitters (SMWLE) with high luminescence efficiency, ultra-long phosphorescence (ULP) and excitation-dependent (ED) color-tunable emission is intriguing and highly desirable from theor. research to practical application. Nevertheless, it is an extremely challenging topic. Here, it is found that three simple terpyridine-based derivatives (P1, P2 and P3) could exhibit unusual multiple emissions and interesting color-tunable emissions. In particular, P3 as the first example could simultaneously achieve bright white light emission with high quantum yield (49%), ultra-long phosphorescence (τ = 0.57 s) and ED color-tunable emission under ambient conditions. Accordingly, it can achieve novel multicolor emission including yellowish green light, white light, blue light, bluish green light and red phosphorescence light in a very wide wavelength range. Both exptl. and theor. studies reveal that such novel emission characteristics are due to the fact that P3 integrates monomer, excimer, and intermol. charge transfer (ICT) triple-mode emissions in the crystalline state. These results provide a rational strategy for the construction of SMWLE and ED color-tunable emission materials. Moreover, such simple multifunctional materials would show huge potential in displays, anti-counterfeiting, and so on. In the experimental materials used by the author, we found 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Synthetic Route of C20H14N4)

4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Synthetic Route of C20H14N4 Pyridine has a conjugated system of six π electrons that are delocalized over the ring.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem