Tag: 200-300

Investigating the Role of Ligand Electronics on Stabilizing Electrocatalytically Relevant Low-Valent Co(I) Intermediates was written by Hickey, David P.;Sandford, Christopher;Rhodes, Zayn;Gensch, Tobias;Fries, Lydia R.;Sigman, Matthew S.;Minteer, Shelley D.. And the article was included in Journal of the American Chemical Society in 2019.Product Details of 1257527-14-2 This article mentions the following:

Cobalt complexes have shown great promise as electrocatalysts in applications ranging from hydrogen evolution to C-H functionalization. However, the use of such complexes often requires polydentate, bulky ligands to stabilize the catalytically active Co(I) oxidation state from deleterious disproportionation reactions to enable the desired reactivity. Herein, we describe the use of bidentate electronically asym. ligands as an alternative approach to stabilizing transient Co(I) species. Using disproportionation rates of electrochem. generated Co(I) complexes as a model for stability, we measured the relative stability of complexes prepared with a series of N,N-bidentate ligands. While the stability of Co(I)Cl complexes demonstrates a correlation with exptl. measured thermodn. properties, consistent with an outer-sphere electron transfer process, the set of ligated Co(I)Br complexes evaluated was found to be preferentially stabilized by electronically asym. ligands, demonstrating an alternative disproportionation mechanism. These results allow a greater understanding of the fundamental processes involved in the disproportionation of organometallic complexes and have allowed the identification of cobalt complexes that show promise for the development of novel electrocatalytic reactions. In the experiment, the researchers used many compounds, for example, (S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole (cas: 1257527-14-2Product Details of 1257527-14-2).

(S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole (cas: 1257527-14-2) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the 闂?bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the 闂?bonds. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Product Details of 1257527-14-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Generation and characterization of 2,6-azulylene was written by Koenig, Thomas;Rudolf, K.;Chadwick, R.;Geiselmann, H.;Patapoff, T.;Klopfenstein, C. E.. And the article was included in Journal of the American Chemical Society in 1986.Safety of 1-Butyl-4-methylpyridin-1-ium bromide This article mentions the following:

A 2:3 syn-anti mixture of [2.2]2,6-azulenophane was prepared and 2,6-azulylene (I) generated by flash vacuum pyrolysis. This nonalternant polyene (I) is reactive, polymerizing via a 2nd-order rate law. However, I can be isolated and characterized at low temperature Proton NMR, Raman and UV spectra all support the structure of I. The syn/anti isomer ratio of the cyclophanes reformed from I is the same as that in the Hofmann-elimination synthesis, suggesting that I is an intermediate in that reaction. Calculations of lowest excited states by the CNDO/S and HAM3/CI models are also reported. Fluorescence and excitation spectra indicate anti-Kasha fluorescence at least in part. In the experiment, the researchers used many compounds, for example, 1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6Safety of 1-Butyl-4-methylpyridin-1-ium bromide).

1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6) belongs to pyridine derivatives. Pyridine has a conjugated system of six 闂?electrons that are delocalized over the ring. The molecule is planar and, thus, follows the H闂佹椿浜滈妴鍗l criteria for aromatic systems. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Safety of 1-Butyl-4-methylpyridin-1-ium bromide

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Mechanism and Enantioselectivity in Palladium-Catalyzed Conjugate Addition of Arylboronic Acids to 闁?Substituted Cyclic Enones: Insights from Computation and Experiment was written by Holder, Jeffrey C.;Zou, Lufeng;Marziale, Alexander N.;Liu, Peng;Lan, Yu;Gatti, Michele;Kikushima, Kotaro;Houk, K. N.;Stoltz, Brian M.. And the article was included in Journal of the American Chemical Society in 2013.Name: (S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole This article mentions the following:

Enantioselective conjugate additions of arylboronic acids to 闁?substituted cyclic enones have been previously reported from our laboratories Air- and moisture-tolerant conditions were achieved with a catalyst derived in situ from palladium-(II) trifluoroacetate and the chiral ligand (S)-t-BuPyOx. We now report a combined exptl. and computational investigation on the mechanism, the nature of the active catalyst, the origins of the enantioselectivity, and the stereoelectronic effects of the ligand and the substrates of this transformation. Enantioselectivity is controlled primarily by steric repulsions between the t-Bu group of the chiral ligand and the 婵?methylene hydrogens of the enone substrate in the enantio-determining carbopalladation step. Computations indicate that the reaction occurs via formation of a cationic arylpalladium-(II) species, and subsequent carbopalladation of the enone olefin forms the key carbon-carbon bond. Studies of nonlinear effects and stoichiometric and catalytic reactions of isolated (PyOx)-Pd-(Ph)I complexes show that a monomeric arylpalladium-ligand complex is the active species in the selectivity-determining step. The addition of water and ammonium hexafluorophosphate synergistically increases the rate of the reaction, corroborating the hypothesis that a cationic palladium species is involved in the reaction pathway. These additives also allow the reaction to be performed at 40 闂佺娅ｉ悡?and facilitate an expanded substrate scope. In the experiment, the researchers used many compounds, for example, (S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole (cas: 1257527-14-2Name: (S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole).

(S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole (cas: 1257527-14-2) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of 闂?8.7 闂?10闂? cm3闁荤姾娅ｅΛ纭俵闂?.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ闁荤姾娅ｅΛ纭俵闂? in the liquid phase and 140.4 kJ闁荤姾娅ｅΛ纭俵闂? in the gas phase. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Name: (S)-4-(tert-Butyl)-2-(4-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Mild regioselective halogenation of activated pyridines with N-bromosuccinimide was written by Canibano, Victoria;Rodriguez, Justo F.;Santos, Mercedes;Sanz-Tejedor, Ascension;Carreno, M. Carmen;Gonzalez, Gema;Garcia-Ruano, Jose L.. And the article was included in Synthesis in 2001.COA of Formula: C5H3Br2NO This article mentions the following:

The regioselective monohalogenation and dihalogenation of pyridines as well as 2,6-dimethoxypyridine with N-bromosuccinimide in different solvents were studied. Reactivity of the substrates decreases in the order amino>hydroxy>methoxy and regioselectivity depends on the position of the substituent (2-substituted > 3-substituted). In most of the cases we obtained monobrominated derivatives regioselectively and in high yields. Hydroxy and amino pyridines can also be dibrominated in almost quant. yield with 2 equiv of NBS. In the experiment, the researchers used many compounds, for example, 2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1COA of Formula: C5H3Br2NO).

2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of 闂?8.7 闂?10闂? cm3闁荤姾娅ｅΛ纭俵闂?.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ闁荤姾娅ｅΛ纭俵闂? in the liquid phase and 140.4 kJ闁荤姾娅ｅΛ纭俵闂? in the gas phase. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.COA of Formula: C5H3Br2NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Effect of chiral ionic liquids on palladium-catalyzed Heck arylation of 2,3-dihydrofuran was written by Roszak, Rafal;Trzeciak, Anna M.;Pernak, Juliusz;Borucka, Nina. And the article was included in Applied Catalysis, A: General in 2011.SDS of cas: 65350-59-6 This article mentions the following:

A relatively small amount of IL (IL = ionic liquid) can dramatically affect conversion in the Heck arylation of 2,3-dihydrofuran with iodobenzene, catalyzed by Pd(OAc)₂ in DMF as a solvent. In all reactions, 2-phenyl-2,3-dihydrofuran (3) was obtained as the main product, and conversion increased even up to 10 times when pyridinium salts with 1-butyl-4-methylpyridinium cation were applied. In a 1:1 mixture of DMF and H₂O as solvent, the addition of ILs led to a remarkable deactivation of the catalyst, and this effect was most visible in the presence of imidazolium salts containing a 1-butyl-3-methylimidazolium cation. The influence of the anionic part of ILs on the reaction course was tested using a series of morpholinium salts and, depending on the anion, conversion varied from 0.4% to even 100%. When morpholinium salts with chiral anions were used, e.e. values of up to 10% were obtained, which is the highest value for the Heck reaction involving IL as a chirality source. In the experiment, the researchers used many compounds, for example, 1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6SDS of cas: 65350-59-6).

1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6) belongs to pyridine derivatives. Pyridine has a conjugated system of six 闂?electrons that are delocalized over the ring. The molecule is planar and, thus, follows the H闂佹椿浜滈妴鍗l criteria for aromatic systems. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.SDS of cas: 65350-59-6

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Derivatives of pyridine. VII. Strength of union of quinquevalent arsenic in the pyridine nucleus was written by Binz, A.;Roth, C.;Maier-Bode, H.. And the article was included in Justus Liebigs Annalen der Chemie in 1930.Product Details of 13472-81-6 This article mentions the following:

The following solubilities are reported (g. in 100 cc. H₂O, temperature not given): 2-pyridone-5-arsonic acid (I) 1.5; Na Salt (II), needles, 51; di-Na salt (III), 37.7; 2-hydroxypyridine-5-arsonic acid (IV), 2; Na Salt (V) 20; di-Na salt (VI), 28.60. On heating 1/200 mol. with 20 cc. H₂O in a bomb tube at 170闂? the following % As are split off in 8 hrs.: I 13.6; II 10.5; III 87.6; IV trace; V trace; VI 11; data are also given for 150闂?and for 2 and 4 hrs. heating. I (11 g.) and 16 g. Br in dilute AcOH give 8 g. 3,5-dibromo-2-pyridone, m. 207闂? IV, however, adds Br with difficulty and from 11 g. there was obtained only 1 g. of impure Br derivative Nitration of IV in H₂SO₄ gives 21% of the NO₂ derivative obtained from I in 75% yields. The filtrate contains about the same amount of 3-nitro-2-hydroxypyridine-5-arsonic acid, does not m. 250闂? 5-Iodo-2-pyridone and K₃AsO₃ with CuSO₄ in KOH, heated 20 hrs., give 30% of I. Similarly, 3-bromo-5-iodo-2-pyridone gives 25% of the 3-br derivative of I, also obtained by direct bromination of I. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6Product Details of 13472-81-6).

3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ闁荤姾娅ｅΛ纭俵闂? in pyridine vs. 150 kJ闁荤姾娅ｅΛ纭俵闂? in benzene). Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Product Details of 13472-81-6

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design, synthesis and fungicidal activity of isothiazole-thiazole derivatives was written by Wu, Qi-Fan;Zhao, Bin;Fan, Zhi-Jin;Zhao, Jia-Bao;Guo, Xiao-Feng;Yang, Dong-Yan;Zhang, Nai-Lou;Yu, Bin;Kalinina, Tatiana;Glukhareva, Tatiana. And the article was included in RSC Advances in 2018.Computed Properties of C11H20N2O2S This article mentions the following:

3,4-Dichloroisothiazoles can induce systemic acquired resistance (SAR) to enhance plant resistance against a subsequent pathogen attack, and oxathiapiprolin exhibits excellent anti-fungal activity against oomycetes targeting at the oxysterol-binding protein. To discover novel chems. with systemic acquired resistance and fungicidal activity, 21 novel isothiazole-thiazole derivatives were designed, synthesized and characterized according to the active compound derivatization method. Compound 6u, with EC₅₀ values of 0.046 mg L^-1 and 0.20 mg L^-1 against Pseudoperonospora cubensis (Berk. et Curt.) Rostov and Phytophthora infestans in vivo, might act at the same target as oxysterol binding protein (PcORP1) of oxathiapiprolin; this result was validated by cross-resistance and mol. docking studies. The expression of the systemic acquired resistance gene pr1 was significantly up-regulated after treating with compound 6u for 24 h (43-fold) and 48 h (122-fold). These results can help the development of isothiazole-thiazole-based novel fungicides. In the experiment, the researchers used many compounds, for example, tert-Butyl 4-carbamothioylpiperidine-1-carboxylate (cas: 214834-18-1Computed Properties of C11H20N2O2S).

tert-Butyl 4-carbamothioylpiperidine-1-carboxylate (cas: 214834-18-1) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Computed Properties of C11H20N2O2S

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Correlation between lipophilicity of newly synthesized ionic liquids and selected Fusarium genus growth rate was written by Vranes, Milan;Tot, Aleksandar;Cosic, Jasenka;Papovic, Snezana;Panic, Jovana;Gadzuric, Slobodan;Jankovic, Nenad;Vrandecic, Karolina. And the article was included in RSC Advances in 2019.Synthetic Route of C10H16BrN This article mentions the following:

The purpose of the present study was to examine the effectiveness of 23 different synthesized ionic liquids (ILs) on Fusarium culmorum and Fusarium oxysporum growth rate. The strategy of IL synthesis was a structural modification of ionic liquids through changing the polarity of imidazolium and pycolinium cations and replacing halide anions with well known antifungal anions (cinnamate, caffeate and mandelate). The findings clearly suggest that the type of alkyl chain on the cation is the most determining factor for IL toxicity. In order to examine how IL structure affects their toxicity towards Fusarium genus, lipophilic descriptor A log P is calculated from d. functional theory and correlated with Fusarium growth rate. All these results demonstrate the high level of the interdependency of lipophilicity and toxicity for investigated ILs towards the Fusarium genus. The data collected in this research suggest that the inhibitory influence of ILs is more pronounced in the case of F. oxysporum. In the experiment, the researchers used many compounds, for example, 1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6Synthetic Route of C10H16BrN).

1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Synthetic Route of C10H16BrN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

PH-Controlled Construction of Cu(I) Coordination Polymers: In Situ Transformation of Ligand, Network Topologies, and Luminescence and UV-vis-NIR Absorption Properties was written by Fang, Zhen-Lan;He, Jian-Gang;Zhang, Qi-Sheng;Zhang, Qi-Kai;Wu, Xiao-Yuan;Yu, Rong-Min;Lu, Can-Zhong. And the article was included in Inorganic Chemistry in 2011.Electric Literature of C12H8N4O This article mentions the following:

Two coordination polymers, [Cu^I₃(L1)I₃]_n (1, L1 = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) and [Cu^I₃(L2)I₂]_n (2, L2 = 2,5-bis(4-pyridyl)-1,2,4-triazolate), are controllably formed by using aqueous ammonia to regulate the pH value of the reaction involving CuI and L1. L2 of 2 is in situ generated from the ring transform of L1 when increase the pH value of the reaction. 1 Exhibits a 2-dimensional layer, while 2 shows 3-dimensional MOFs with a novel 3-nodal 4,4,5-connected net topol. of an unprecedented Point (Schlafli) symbol: (4闁?²闁?²闁?)(5⁴闁?²)(4³闁?闁?⁶). Although both 1 and 2 are built of CuI and similar ligands, different arrangements of CuI chains and ligands endow them with different phys. properties. 1 Displays a strong pure red luminescence emission, while 2 is non-luminescent and shows a broad absorption band covering the whole UV-visible-NIR spectrum range. The emissive excited states of 1 and the charge transitions of the optical absorption for 2 are solved by DFT calculations In the experiment, the researchers used many compounds, for example, 2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7Electric Literature of C12H8N4O).

2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ闁荤姾娅ｅΛ纭俵闂? in pyridine vs. 150 kJ闁荤姾娅ｅΛ纭俵闂? in benzene). Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Electric Literature of C12H8N4O

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design, synthesis and anti-HBV activity evaluation of new substituted imidazo[4,5-b]pyridines was written by Gerasi, Maria;Frakolaki, Efseveia;Papadakis, Georgios;Chalari, Anna;Lougiakis, Nikolaos;Marakos, Panagiotis;Pouli, Nicole;Vassilaki, Niki. And the article was included in Bioorganic Chemistry in 2020.Synthetic Route of C5H3Cl2N3O2 This article mentions the following:

The design and synthesis of a number of new imidazo[4,5-b]pyridines is described. The heterocyclic scaffold possesses 6-chloro- or 5,6-dichloro-substitution and bears various 2-alkylamino-Me or Et groups. The corresponding N¹ and N³-tosylates are also presented. The anti-HBV activity of the compounds was evaluated in HBV infectious system at the level of HBV rcDNA secretion and CC₅₀, EC₅₀ and selectivity index values were determined The tosylates showed low antiviral potency and relatively high cytotoxicity, on the contrary, a number of 2,5 and/or-6-substituted imidazopyridines, mainly those belonging to the 6-chloroimidazo[4,5-b]pyridine series, were endowed with a very interesting profile and were further investigated. The most promising among them, along with the reduction of the secreted HBV rcDNA, also caused a reduction in HBV cccDNA and pgRNA levels, with a concomitant accumulation of the intracellular encapsidated rcDNA. Surprisingly, the most active 6-chloro-2-[2-(diethylamino)ethyl]imidazo[4,5-b]pyridine was highly competitive to interferon. In the experiment, the researchers used many compounds, for example, 5,6-Dichloro-3-nitropyridin-2-amine (cas: 203794-33-6Synthetic Route of C5H3Cl2N3O2).

5,6-Dichloro-3-nitropyridin-2-amine (cas: 203794-33-6) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Synthetic Route of C5H3Cl2N3O2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem