Tag: 100-200

Kinetics and mechanism of the electrophilic substitution of heteroaromatic compounds. XL. Standardization of aromatic and heteroaromatic nitration rates was written by Katritzky, Alan R.;Terem, Bulent;Scriven, Eric V.;Clementi, Sergio;Tarhan, H. Okan. And the article was included in Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) in 1975.COA of Formula: C7H9NO This article mentions the following:

Methods for extrapolating rates for nitrations in aqueous H2SO4 to different temperatures and acidities are discussed. The determination of standard (25鎺? H0 -6.6) nitration rates (k20) from exptl. measured rates required 4 consecutive steps: determination of the observed rate (k2) at the individual acidity and temperature, involving knowledge of the acidity function followed and its variation with temperature, determination of k2(T) at H0 -6.6, involving construction of the rate profile and its extrapolation to the proper acidity, determination of k2 (25鎺? at the standard acidity, involving evaluation or estimation of the thermodn. parameters at that acidity, and determination of k20, involving correction for minority species reaction, which requires knowledge of the pKa of the substrate at the standard temperature The procedure was applied to literature data for 131 nitration rates. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8COA of Formula: C7H9NO).

3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. Pyridine has a conjugated system of six 锜?electrons that are delocalized over the ring. The molecule is planar and, thus, follows the H鐪塩kel 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.COA of Formula: C7H9NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

One-pot deconstruction and conversion of lignocellulose into reducing sugars by pyridinium-based ionic liquid-metal salt system was written by Naz, Sadia;Uroos, Maliha;Asim, Azmat Mehmood;Muhammad, Nawshad;Shah, Faiz Ullah. And the article was included in Frontiers in Chemistry (Lausanne, Switzerland) in 2020.Application In Synthesis of 1-Butyl-3-methylpyridinium Chloride This article mentions the following:

Constantly decreasing fossil resources and exceeding energy demands are the most alarming concerns nowadays. The only way out is to develop efficient, safe, and economical biomass processing protocols that can lead toward biofuels and fine chems. This research is one of such consequences involving the deconstruction and conversion of wheat straw carbohydrate constituents into reducing sugars via one-pot reaction promoted by Lewis acidic pyridinium-based ionic liquids (PyILs) mixed with different metal salts (MCl). Various parameters such as the type of metal salt, loading amount of metal salt, time, temperature, particle size of biomass, and water content which affect the deconstruction of wheat straw have been evaluated and optimized. Among the studied ionic liquid (IL) and metal salt systems, the best results were obtained with [BMPy]+CoCl-3. The dinitrosalicylic acid (DNS) assay was used to determine the percentage of total reducing sugars (TRS) generated during treatment of wheat straw. The deconstructed wheat straw was characterized with various anal. tools, i.e., Fourier transform IR (FTIR) spectroscopy, SEM (SEM), and X-ray powder diffraction (XRD) analyses. The IL-metal salt system was recycled for subsequent treatment of wheat straw. Statistical parameters were calculated from anal. of variance (ANOVA) at the 0.05 level of confidence. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Application In Synthesis of 1-Butyl-3-methylpyridinium Chloride).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) belongs to pyridine derivatives. Pyridine has a conjugated system of six 锜?electrons that are delocalized over the ring. The molecule is planar and, thus, follows the H鐪塩kel 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.Application In Synthesis of 1-Butyl-3-methylpyridinium Chloride

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Electrooxidative and Regioselective C-H Azolation of Phenol and Aniline Derivatives was written by Feng, Pengju;Ma, Guojian;Chen, Xiaoguang;Wu, Xing;Lin, Ling;Liu, Peng;Chen, Tianfeng. And the article was included in Angewandte Chemie, International Edition in 2019.Product Details of 51834-97-0 This article mentions the following:

A general and practical protocol was developed for the regioselective C-H azolation of phenol and aniline derivatives by electrooxidative cross-coupling [e.g., 4-methoxyphenol + pyrazole 閳?4-methoxy-2-(1H-pyrazol-1-yl)phenol (97%)]. The reaction occurs under metal-, oxidant-, and reagent-free conditions, allowing access to a wide variety of synthetically useful heteroarene derivatives The reaction also tolerates a broad range of functional groups and is amenable to gram-scale synthesis. Finally, a preliminary mechanistic study indicated that a radical-radical-combination pathway might be involved in the coupling reaction. In the experiment, the researchers used many compounds, for example, 5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0Product Details of 51834-97-0).

5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Product Details of 51834-97-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Fluorine-19 nuclear magnetic resonance study of some titanium tetrafluoride-substituted pyridine 1-oxide adducts was written by Dyer, Daniel S.;Ragsdale, Ronald O.. And the article was included in Inorganic Chemistry in 1969.Electric Literature of C7H9NO This article mentions the following:

A 19F N.M.R. study of several substituted pyridine 1-oxide adducts of TiF4 is reported. Evidence for the existence of a number of trans-TiF4.2(donor) complexes is presented and discussed. Mixed adducts of TiF4 in which the donor mols. are oriented trans to each other in solution are reported for the first time. The factors which determine the stereochemistry of the TiF4.2-(donor) complexes are discussed. It appears that trans-TiF4.2-(donor) is formed only when there is sufficient steric interaction to overcome symmetry effects and the tendency to maximize p锜?d锜?bonding. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Electric Literature of C7H9NO).

3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) 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. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C閳ユ弻 in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Electric Literature of C7H9NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Base-catalyzed reactions. XXXVII. Relative rates of side-chain alkenylation of 4-substituted pyridines with isoprene. Effects of the side-chain double bond on reaction rates was written by Stalick, Wayne M.;Pines, Herman. And the article was included in Journal of Organic Chemistry in 1970.Computed Properties of C11H17N This article mentions the following:

The competitive side-chain alkenylation of various 4-alkyl- and alkenylpyridines with isoprene catalyzed by alkali metals was investigated. Examination of the alkylpyridines used in the reaction shows that steric factors are important when substitution is made on the carbon 灏?to the pyridine ring. The presence of a side-chain double bond increases the rate of alkenylation and this is ascribed to a complexation of the olefinic bond with the alkali metal catalyst. The relative increase in competitive rate varies with the catalyst used in the reaction, such that K > na > Li. The changes in reactivity that occur when using different catalysts are explained by the hard and soft acids and bases (HSAB) principle. A table identifying many new 4-substituted pyridine compounds is also given. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0Computed Properties of C11H17N).

4-Hexylpyridine (cas: 27876-24-0) 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. 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. Computed Properties of C11H17N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Nickel-Catalyzed Cross-Coupling of Aryl 2-Pyridyl Ethers with Organozinc Reagents: Removal of the Directing Group via Cleavage of the Carbon-Oxygen Bonds was written by Dai, Wei-Can;Yang, Bo;Xu, Shi-He;Wang, Zhong-Xia. And the article was included in Journal of Organic Chemistry in 2021.Related Products of 4783-68-0 This article mentions the following:

Reaction of aryl 2-pyridyl ethers with arylzinc reagents under catalysis of NiCl₂(PCy₃)₂ afforded aryl-aryl cross-coupling products Ar²Ar¹ [R = Ph, 4-FC₆H₄, 4-MeOC₆H₄, etc.; Ar¹ = 4-N(Me)₂C₆H₄, 4-MeC₆H₄, 4-MeOC₆H₄, etc.] via selective cleavage of CAr-OPy bonds. The reaction features a wide substrate range and good compatibility of functional groups. 灏?H-free alkylzinc reagents were also applicable as the nucleophiles in the transformation, whereas 灏?H-containing alkylzinc reagents led to a mixture of cross-coupling and hydrogenation products Ar²Ar¹. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Related Products of 4783-68-0).

2-Phenoxypyridine (cas: 4783-68-0) 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. 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.Related Products of 4783-68-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

2-(Pyridinium-1-yl)-1,1-bis(triflyl)ethanides: structural behaviour and availability as bis(triflyl)ethylating reagents was written by Yanai, Hikaru;Takahashi, Yoichi;Fukaya, Haruhiko;Dobashi, Yasuo;Matsumoto, Takashi. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2013.Related Products of 644-98-4 This article mentions the following:

Stable and easy-to-handle zwitterions containing carbanion and pyridinium moieties were synthesized, and their structural studies by both X-ray crystallog. and theor. methods revealed the stereoelectronic effect in the zwitterionic ‘C^–-C-N⁺‘ system. In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Related Products of 644-98-4).

2-Isopropylpyridine (cas: 644-98-4) 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.Related Products of 644-98-4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Immobilization of Candida rugosa lipase onto an eco-friendly support in the presence of ionic liquid was written by Cabrera-Padilla, Rebeca Y.;Lisboa, Milena C.;Pereira, Matheus M.;Figueiredo, Renan T.;Franceschi, Elton;Fricks, Alini T.;Lima, Alvaro S.;Silva, Daniel P.;Soares, Cleide M. F.. And the article was included in Bioprocess and Biosystems Engineering in 2015.Recommanded Product: 125652-55-3 This article mentions the following:

Candida rugosa lipase (CRL) was immobilized on an eco-friendly support poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV), by phys. adsorption, using different ionic liquids (ILs) as immobilization additives. This was to investigate the influence of cationic core ([C₄mpy]Cl, [C₄min]Cl), of anions ([C₄min]Cl, [C₄min]N(CN)₂, [C₄min]Tf₂N), and of cation chain length ([C₂min]Tf₂N, [C₄min]Tf₂N) in the immobilization process. The immobilized biocatalysts (IB) were characterized with respect to the morphol., physico-chem. properties, total activity recovery yield (Ya), and biochem. properties of more efficient IB were evaluated. Initially, it was found that the change of cationic core did not influence Ya compared to the control. With change of anions, it was seen that the best result was obtained for the more hydrophobic anion (Tf₂N), and finally increasing the cation chain length increased Ya. IB most efficient with [C₄min]Tf₂N obtained 78 % of Ya, more than twice the control value (30 %) and a considerable enhancement of operational stability compared with the control. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Recommanded Product: 125652-55-3).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) 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 groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Recommanded Product: 125652-55-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem