Day: February 9, 2023

Alkylation of pyridine in free radical chain reactions utilizing alkylmercurials was written by Russell, Glen A.;Guo, Deliang;Khanna, Rajive K.. And the article was included in Journal of Organic Chemistry in 1985.HPLC of Formula: 27876-24-0 This article mentions the following:

Pyridines or N,N,N‘,N‘-tetramethyl-p-phenylenediamine will undergo a photostimulated free radical chain reaction with alkylmercury halides or carboxylates yielding ring alkylated substitution products. Alkene mercuration products can be used without isolation for the alkylation reaction. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0HPLC of Formula: 27876-24-0).

4-Hexylpyridine (cas: 27876-24-0) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.HPLC of Formula: 27876-24-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design and synthesis of 1-aryl-5-anilinoindazoles as c-Jun N-terminal kinase inhibitors was written by Jiang, Rong;Frackowiak, Bozena;Shin, Youseung;Song, Xinyi;Chen, Weimin;Lin, Li;Cameron, Michael D.;Duckett, Derek R.;Kamenecka, Theodore M.. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2013.Product Details of 89978-52-9 This article mentions the following:

Starting from a pyrazole HTS (high throughput screening) hit, a series of 1-aryl-1H-indazoles have been synthesized as JNK3 inhibitors with moderate selectivity against JNK1. SAR studies led to the synthesis of a double digital nanomolar JNK3 inhibitor (I) with good in vivo exposure. In the experiment, the researchers used many compounds, for example, Ethyl 2-bromoisonicotinate (cas: 89978-52-9Product Details of 89978-52-9).

Ethyl 2-bromoisonicotinate (cas: 89978-52-9) 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.Product Details of 89978-52-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Preparation of some substituted 2,6-bis(2-pyridyl)pyridines was written by Case, Francis H.;Kasper, Thomas J.. And the article was included in Journal of the American Chemical Society in 1956.Recommanded Product: 2-Bromo-4-phenylpyridine This article mentions the following:

The appropriate 2- or 4-substituted pyridine (1 mole), 1.18 moles NaNH₂, and 2.2 moles PhNMe₂ heated 6 hrs. at 150-60° (130-40° with 4-ethylpyridine), cooled, and poured into H₂O, the organic layer dried, the PhNMe₂ distilled, and the residue distilled or recrystallized gave the corresponding substituted-2-aminopyridine (I) (substituent, % yield, and m.p. given): 4-Et, 53, 70-1° (from pert. ether); 4-Ph, 53, 164-5° (from C₆H₆); 6-Ph, 70, 71-2° (from petr. ether). The appropriate I (0.3 mole) in 175 cc. 48% HBr treated with 42 cc. Br, the mixture treated gradually with 52 g. NaNO₂ in 74 cc. H₂O below 5° and then with 112 g. NaOH in 285 cc. H₂O below 20°, and extracted with Et₂O, the extract evaporated, and the residue distilled in vacuo or recrystd, gave the corresponding substituted-2-bromopyridines (II) (substituent, % yield, and b.p./mm. or m.p. given): 4-Et, 88, 103-5°/11; 4-Ph, 63, 65-6° (from petr. ether); 6-Ph, 62, 51-2° (from petr. ether). The appropriate II (1 mole) and 1.1 moles CuCN heated gently with a smoky flame to beginning reaction, the mixture evacuated as quickly as possible to 5 mm. (40 mm. with the Me derivative), and the reaction product distilled rapidly gave the corresponding substituted-2-cyanopyridine (substituent, % yield, and m.p. given): 4-Me (III), 28, 88-9°; 4-Ph (IV), 60, 99-100°; 6-Ph (IVa), 67, 64-6°; 4-Et (V), 61, -(b₁₁ 123-4°). III (11.8 g.) in 125 cc. dry C₆H₆ and 100 cc. Et₂O treated with MeMgI from 35.5 g. MeI and 6 g. Mg in Et₂O, the mixture warmed to room temperature, stirred 1 hr., and decomposed with cold aqueous NH₄Cl, and the Et₂O layer worked up yielded 8.0 g. 2-acetyI-4-methylpyridine (VI), b₁₅ 95-7°, m. 33-4° (from petr. ether). V (13.2 g.) gave similarly 7.0 g. 4-Et homolog of VI. IVa (20 g.) refluxed 5 hrs. with 220 cc. saturated alc. HCl, cooled, filtered, concentrated in vacuo on the steam bath, cooled, poured into H₂O, and neutralized with NH₄OH precipitated 79% 2-carbethoxy-6-phenylpyridine (VII), colorless solid, m. 50-7°. IV (17.3 g.) yielded similarly 15.8 g. 4-Ph isomer (VIII) of VII, m. 60-1° (from petr. ether). VII (20 g.) and 14 g. dry EtOAc added with stirring to 9.2 g. NaOEt in 125 cc. dry C₆H₆, the mixture refluxed 21 hrs. with stirring, cooled, poured into 4.4 g. NaOH in 90 cc. H₂O, and the Et₂O layer worked up gave 9.3 g. 2-acetyl-6-phenylpyridine (IX), m. 75-6° (from petr. ether). VIII (14.5 g.) gave similarly 7.5 g. 4-Ph isomer of IX, m. 75-6°. 2-Bromo-4-phenylpyridine (6 g.) and 6 g. Cu powder in 12 g. Ph₂ heated 3 hrs. with stirring at 250° the mixture finely powdered and extracted with concentrated HCl, the acid solution basified with aqueous NaOH-NH₄OH and extracted with Et₂O, and the extract worked up gave 0.7 g. 4,4′-diphenyl-2,2′-bipyridine (X), m. 187-8°. 2-Bromo-4-ethylpyridine (28 g.) and 43.5 g. Cu powder heated 1 hr. at 200-20° and worked up in the usual manner gave 4.0 g. di-Et analog (XI) of X, colorless liquid, b_0.3 147-50°. XI in Et₂O treated with dry HCl gave XI.2HCl, m. 193-5° (from EtOH-Me₂CO). The appropriate 2-acetylpyridine or -quinoline (not over 5 g., 2.2 molar proportions), 1 mole BzH, 0.3 mole NH₄OAc, and 9 moles 28% NH₄OH heated 5 hrs. in a sealed tube at 250°, and the product isolated with hot C₆H₆ gave the following 2,6-bis-substituted-2-pyridyl)-4-phenylpyridines (substituent, % yield, and m.p. given): 4-Me, 18, 328-9° (from C₆H₆); 4-Et, 16, 114-15° (from petr. ether); 6-Ph, 17, 190-1° (from petr. ether); 4-Ph, 21, 257-8° (from EtNO₂). 2,6Bis(2-quinolyl)-4-phenylpyridine, 18, 295-6° (from C₆H₆). In the experiment, the researchers used many compounds, for example, 2-Bromo-4-phenylpyridine (cas: 54151-74-5Recommanded Product: 2-Bromo-4-phenylpyridine).

2-Bromo-4-phenylpyridine (cas: 54151-74-5) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). 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.Recommanded Product: 2-Bromo-4-phenylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Efficient Phosphorus-Free Chlorination of Hydroxy Aza-Arenes and Their Application in One-Pot Pharmaceutical Synthesis was written by Wang, Jian;Li, Yan-Hui;Pan, Song-Cheng;Li, Ming-Fang;Du, Wenting;Yin, Hong;Li, Jing-Hua. And the article was included in Organic Process Research & Development in 2020.Application In Synthesis of Pyridin-4-ol This article mentions the following:

The chlorination of hydroxy aza-arenes with bis(trichloromethyl) carbonate (BTC) and SOCl₂ has been effectively performed by refluxing with 5 weight % 4-(dimethylamino)pyridine (DMAP) as a catalyst. Various substrates are chlorinated with high yields. The obtained chlorinated aza-arenes can be used directly with simple workup for succedent one-pot synthesis on a large scale. In the experiment, the researchers used many compounds, for example, Pyridin-4-ol (cas: 626-64-2Application In Synthesis of Pyridin-4-ol).

Pyridin-4-ol (cas: 626-64-2) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Application In Synthesis of Pyridin-4-ol

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Multimetallic Ni- and Pd-Catalyzed Cross-Electrophile Coupling To Form Highly Substituted 1,3-Dienes was written by Olivares, Astrid M.;Weix, Daniel J.. And the article was included in Journal of the American Chemical Society in 2018.Computed Properties of C10H17NO2 This article mentions the following:

The synthesis of highly substituted 1,3-dienes from the coupling of vinyl bromides with vinyl triflates is reported for the first time. The coupling is catalyzed by a combination of (5,5′-bis(trifluoromethyl)-2,2′-bipyridine)NiBr₂ and (1,3-bis(diphenylphosphino)propane)PdCl₂ in the presence of a zinc reductant. This method affords tetra- and penta-substituted 1,3-dienes that would otherwise be difficult to access and tolerates electron-rich and -poor substituents, heterocycles, an aryl bromide, and a pinacol boronate ester. Mechanistically, the reaction appears to proceed by an unusual zinc-mediated transfer of a vinyl group between the nickel and palladium centers. In the experiment, the researchers used many compounds, for example, tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4Computed Properties of C10H17NO2).

tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Computed Properties of C10H17NO2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Selective α-Deuteration of Cinnamonitriles using D₂O as Deuterium Source was written by Guo, Beibei;de Vries, Johannes G.;Otten, Edwin. And the article was included in Advanced Synthesis & Catalysis in 2022.Formula: C12H9NO This article mentions the following:

The selective α-deuteration of α,β-unsaturated nitriles using the strong base t-BuOK or a metal-ligand cooperative Ru pincer catalyst was described. With D₂O as deuterium source and glyme as solvent at 70°C, t-BuOK is an efficient catalyst for deuteration at the α-C(sp²) position of cinnamonitriles, providing access to a broad range of deuterated derivatives in good to excellent yields and with very high levels of deuterium incorporation. While the t-BuOK-catalyzed protocol does not tolerate base-sensitive functional groups, cinnamonitrile derivatives containing a benzylic bromide or ester moiety were deuterated in excellent yields using Milstein’s ruthenium PNN pincer catalyst. Moreover, the activity for H/D exchange of the metal-ligand cooperative Ru catalyst was found to be significantly higher than that of t-BuOK, allowing reactions to proceed well even at room temperature A mechanistic proposal is put forward that involves deprotonation of the cinnamonitrile α-CH position when using t-BuOK as catalyst, whereas H/D exchange catalysis with the Ru PNN pincer likely proceeds via (reversible) oxa-Michael addition of D₂O. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Formula: C12H9NO).

Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. 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.Formula: C12H9NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Cyrene as a Bio-Based Solvent for the Suzuki-Miyaura Cross-Coupling was written by Wilson, Kirsty L.;Murray, Jane;Jamieson, Craig;Watson, Allan J. B.. And the article was included in Synlett in 2018.Name: 5-Hydroxy-2-methoxylpyridine This article mentions the following:

The Suzuki-Miyaura (SM) cross-coupling is the most broadly utilized Pd-catalyzed C-C bond-forming reaction in the chem. industry. A large proportion of SM couplings employ dipolar aprotic solvents; however, current sustainability initiatives and increasingly stringent regulations advocate the use of alternatives that exhibit more desirable properties. Here the scope and utility of the bio-derived solvent Cyrene in SM cross-couplings and evaluate its suitability as a reaction medium for this benchmark transformation from discovery to gram scale is described. In the experiment, the researchers used many compounds, for example, 5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0Name: 5-Hydroxy-2-methoxylpyridine).

5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. 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: 5-Hydroxy-2-methoxylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Decarboxylation of orotic acid analogues: Comparison of solution and gas-phase reactivity was written by Wong, Amy;Vikse, Krista;Wu, Weiming. And the article was included in Tetrahedron Letters in 2020.Recommanded Product: 59864-31-2 This article mentions the following:

The decarboxylation of orotic acid and analogs have been investigated as a model for enzymic decarboxylation catalyzed by orotidine-5′-monophosphate decarboxylase (ODCase). The rate of decarboxylation of 1-methyl-4-pyridone-2-carboxylic acid in solution has been reported to be three orders of magnitude greater than those of 1,3-dimethylorotic acid and 1-methyl-2-pyridone-6-carboxylic acid in solution Here, the gas-phase decarboxylation of the three corresponding carboxylates were investigated. The carboxylate of 1,3-dimethylorotic acid decarboxylates at a faster rate and thus the relative rates of decarboxylation are different from those observed in solution The relative rates of decarboxylation correlate well with the stability of the corresponding carbanions and the calculated activation energies for gas-phase decarboxylation. Therefore, the reactions in the gas phase seem to go through the direct decarboxylation mechanism whereas the reactions in solution likely go through zwitterionic intermediates as previously proposed. In the experiment, the researchers used many compounds, for example, 1-Methyl-6-oxo-1,6-dihydropyridine-2-carboxylic acid (cas: 59864-31-2Recommanded Product: 59864-31-2).

1-Methyl-6-oxo-1,6-dihydropyridine-2-carboxylic acid (cas: 59864-31-2) 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. 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.Recommanded Product: 59864-31-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Dodecylpyridinium chloride removal by persulfate activation using UVA radiation or temperature: experimental design and kinetic modeling was written by Nunes, Roberta Frinhani;Metolina, Patricia;Teixeira, Antonio Carlos Silva Costa. And the article was included in Environmental Science and Pollution Research in 2021.Electric Literature of C17H30BrN This article mentions the following:

The degradation of dodecylpyridinium chloride (DPC) by SO₄^–· and HO· radicals, generated by UVA and thermal-activated persulfate (PS) was investigated. Temperatures of 30-50°C were used for the heat activation of PS. In the case of UVA/PS, the effects of [PS]₀ and specific photon emission rate (EP,0) were studied through a Doehlert design coupled with statistical anal. and response surface methodol. The results showed high DPC removal (99.8%) and pseudo-first-order degradation rate (k_obs = 0.0971 min^-1) for [DPC]₀ = 4.60 ± 0.11 mg L^-1, [PS]₀ = 7.75 mmol L^-1, and EP,0 = 0.437μmol photons L^-1 s^-1, with a major role of SO₄^–· radicals in comparison with HO·. The specific DPC degradation rate found under these conditions was higher than that observed for thermal activation at 50°C and [PS]₀ = 5.5 mmol L^-1 (k_obs = 0.0712 min^-1) over the same time, although complete DPC removal was also achieved in the latter. The pos. effect of EP,0 on DPC degradation by the UVA/PS process depends on PS concentrations, with kobs values increasing linearly with [PS]₀ in the range 7.75-10 mmol L^-1, whereas lower EP,0 values can be compensated by increasing [PS]₀ up to about 10 mmol L^-1, without significant scavenging. The second-order rate constants of DPC with HO· and SO₄^–·, estimated by comprehensive kinetic modeling, were 8.26 x 10⁹ and 4.44 x 10⁹ L mol^-1 s^-1, resp. Furthermore, higher [DPC]₀ would neg. affect the DPC degradation rate by the UVA/PS process, while 62% DPC removal was obtained in WWTP water, which can be considered good given the complexity of the real matrix. Finally, our results shed light on the possibility of using available UVA radiation (4.5%) in solar irradiance on the Earth’s surface, making this treatment process more sustainable and cost-effective. In the experiment, the researchers used many compounds, for example, 1-Dodecylpyridin-1-ium bromide (cas: 104-73-4Electric Literature of C17H30BrN).

1-Dodecylpyridin-1-ium bromide (cas: 104-73-4) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel 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.Electric Literature of C17H30BrN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Nickel-Catalyzed Suzuki-Miyaura Coupling of Heteroaryl Ethers with Arylboronic Acids was written by Li, Xiao-Jian;Zhang, Jin-Ling;Geng, Yu;Jin, Zhong. And the article was included in Journal of Organic Chemistry in 2013.Quality Control of 2-Phenoxypyridine This article mentions the following:

Nickel-catalyzed Suzuki-Miyaura coupling of heteroaryl ethers with arylboronic acids was described. Selective activation of the phenol C-O bonds was achieved by converting them into the corresponding aryl 2,4-dimethoxy-1,3,5-triazin-6-yl ethers, in which the aryl C-O bond could be selectively cleaved with inexpensive, air-stable NiCl₂(dppf) as a catalyst. Coupling of these readily accessible heteroaryl ethers proved tolerant of extensive functional groups. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Quality Control of 2-Phenoxypyridine).

2-Phenoxypyridine (cas: 4783-68-0) 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. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Quality Control of 2-Phenoxypyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem