Tag: 100-200

2,5- and 5,6-Dihalonicotinic acids and their precursors. II was written by Setliff, Frank L.;Rankin, Gary O.. And the article was included in Journal of Chemical and Engineering Data in 1972.Category: pyridine-derivatives This article mentions the following:

2-Chloro- and 2-bromo-5-fluoronicotinic acid and 6-chloro- and 6-bromo-5-fluoronicotinic acid were prepared (25-68%) by oxidation of dihalo-3-picolines. Spectral data for the acids, two of the dihalopicolines, and their amino-halo precursors was determined In the experiment, the researchers used many compounds, for example, 2-Bromo-5-fluoro-3-methylpyridine (cas: 38186-85-5Category: pyridine-derivatives).

2-Bromo-5-fluoro-3-methylpyridine (cas: 38186-85-5) 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.Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Synthesis of 2-ethylisonicotinic thioamide was written by Kucherova, N. F.;Khomutov, R. M.;Budovskii, E. I.;Evdakov, V. P.;Kochetkov, N. K.. And the article was included in Zhurnal Obshchei Khimii in 1959.Related Products of 156761-88-5 This article mentions the following:

2-ethylpyridine was added 558 ml. AcO₂H solution in AcOH (containing 54.7 g. AcO₂H and stabilized with 5.5 g. H₂SO₄) at 70-80°. On the following day the mixture was concentrated in vacuo and the sirupy N-oxide was taken up in 112 ml. H₂SO₄ and added to 136 ml. HNO₃ (d. 1.51) and 75 ml. H₂SO₄, heated 1.5-2 hrs. at 100°, left overnight, then poured on ice and neutralized with NH₄OH. Extraction with Et₂O gave 49% 2-ethyl-4-nitropyridine N-oxide, m. 94-6°. This refluxed (with stirring) 8 hrs. with Fe filings and AcOH-H₂SO₄ gave, after the usual treatment, 89% 2-ethyl-4-aminopyridine (I), b_4-5 128-30°; HCl salt m. 54-6°. The amine (15.4 g.) in 40 ml. 50% HBr was treated with 13 ml. Br at -5°, followed by 21.6 g. NANO₂ in 31 ml. H₂O, stirred 0.5 hr., treated with 47 g. NaOH in 50 ml. H₂O at 20-5° and extracted with Et₂O; the extract gave 90% 2-ethyl-4-bromopyridine (II), b₃₀ 97-8°. I (14 g.) in 300 ml. concentrated HCl was saturated with dry HCl at -20°, then treated with 43 g. powd. NaNO₂ and kept overnight; after concentration and treatment with 40% NaOH, the mass was extracted with Et₂O, yielding 86% 2-ethyl-4-chloropyridine, b_18-19 76-8°; HCl salt m. 179-80°. Heating 21 g. II with 10 g. Cu₂(CN)₂ 1 hr. at 160-70° gave 73% 2-ethylisonicotinonitrile, b₂₉ 106-10°. This (11 g.) in 11 ml. pyridine and 8.7 g. Et₃N was saturated with H₂S (1 hr.) and quenched in H₂O, yielding 87% 2-ethylisonicotinic thioamide, m. 163-4° (from EtOH); HCl salt m. 212-4°. In the experiment, the researchers used many compounds, for example, 4-Bromo-2-ethylpyridine (cas: 156761-88-5Related Products of 156761-88-5).

4-Bromo-2-ethylpyridine (cas: 156761-88-5) 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.Related Products of 156761-88-5

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Switching the reactivity of cyanomethylpyridinium salts in the 1,3-cycloaddition conditions with alkyl propiolates to cyanoindolizines or cyanoazaindolizinyl-indolizines was written by Moise, Iuliana-Monica;Ghinet, Alina;Shova, Sergiu;Bicu, Elena. And the article was included in Tetrahedron in 2020.Reference of 17281-59-3 This article mentions the following:

A particular reactivity of 1-cyanomethylpyridinium salts was revealed in the [3 + 2] cycloaddition conditions with alkyl propiolates. Cyanoindolizines I [R = H, 7-Me, 7-OMe, etc.] were obtained in reactions carried out at room temperature while refluxing in CH₃CN provided unexpected Et or Me 3-(3-cyanoimidazo[1,2-a]pyridin-2-yl)indolizine-1-carboxylates II. The structure of the new 2:1 azaindolizine-indolizine adducts was secured by X-ray anal. Methodol. efforts had enabled the adjustment of the reactivity towards the formation of 3-cyanoindolizines I or cyanoazaindolizine-indolizines II. A mechanism for the formation of azaindolizine-indolizines was proposed. In the experiment, the researchers used many compounds, for example, 1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3Reference of 17281-59-3).

1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3) 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.Reference of 17281-59-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design and Synthesis of 56 Shape-Diverse 3D Fragments was written by Downes, Thomas D.;Jones, S. Paul;Klein, Hanna F.;Wheldon, Mary C.;Atobe, Masakazu;Bond, Paul S.;Firth, James D.;Chan, Ngai S.;Waddelove, Laura;Hubbard, Roderick E.;Blakemore, David C.;De Fusco, Claudia;Roughley, Stephen D.;Vidler, Lewis R.;Whatton, Maria Ann;Woolford, Alison J.-A.;Wrigley, Gail L.;O’Brien, Peter. And the article was included in Chemistry – A European Journal in 2020.Product Details of 59718-84-2 This article mentions the following:

Fragment screening collections were often predominantly populated with flat, 2D mols. A workflow for the design and synthesis of 56 3D disubstituted pyrrolidine and piperidine fragments that occupy under-represented areas of fragment space (as demonstrated by a principal moments of inertia (PMI) anal.) was described. A key, and unique, underpinning design feature of this fragment collection was that assessment of fragment shape and conformational diversity (by considering conformations up to 1.5 kcal mol^-1 above the energy of the global min. energy conformer) was carried out prior to synthesis and was also used to select targets for synthesis. The 3D fragments were designed to contain suitable synthetic handles for future fragment elaboration. Finally, by comparing our 3D fragments with six com. libraries, it was clear that our collection was high three-dimensionality and shape diversity. In the experiment, the researchers used many compounds, for example, Methyl 3-methylpicolinate (cas: 59718-84-2Product Details of 59718-84-2).

Methyl 3-methylpicolinate (cas: 59718-84-2) 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. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Product Details of 59718-84-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Graphene oxide grafted with Pd₁₇Se₁₅ nano-particles generated from a single source precursor as a recyclable and efficient catalyst for C-O coupling in O-arylation at room temperature was written by Joshi, Hemant;Sharma, Kamal Nayan;Sharma, Alpesh K.;Prakash, Om;Singh, Ajai Kumar. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2013.SDS of cas: 4783-68-0 This article mentions the following:

The Pd₁₇Se₁₅ nanoparticles, synthesized for the first time from a single source precursor [Pd(L)Cl₂] {L = 1,3-bis(phenylselenyl)propan-2-ol} and grafted onto graphene oxide, show high catalytic activity in C-O coupling between aryl/heteroaryl chlorides/bromides and phenol at room temperature (Pd loading 1 mol%; yield up to 94%). Pd(L)Cl₂ was characterized by x-ray crystallog., and was found to be catalytically inactive on its own. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0SDS of cas: 4783-68-0).

2-Phenoxypyridine (cas: 4783-68-0) 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. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.SDS of cas: 4783-68-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Gram-Scale Synthesis of β-(Hetero)arylethenesulfonyl Fluorides via a Pd(OAc)₂ Catalyzed Oxidative Heck Process with DDQ or AgNO₃ as an Oxidant was written by Zha, Gao-Feng;Bare, Grant A. L.;Leng, Jing;Shang, Zhen-Peng;Luo, Zhixiong;Qin, Hua-Li. And the article was included in Advanced Synthesis & Catalysis in 2017.HPLC of Formula: 1072951-54-2 This article mentions the following:

A practical oxidative Heck reaction between organoboronic acids and ethenesulfonyl fluoride (ESF) was developed. Aryl- and heteroaryl-boronic acids reacted efficiently and stereoselectively with ESF in the presence of a catalytic amount of Pd(OAc)₂ and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) or AgNO₃ in AcOH to afford the corresponding E-isomer of β-arylethenesulfonyl fluoride products. The utility of this reaction was exemplified by an expanded scope of 47 examples including N-, O-, and S-containing heteroaromatics, demonstrating chemoselectivity over aryliodides and gram-scale operation without the requirement for strict anhydrous or oxygen-free conditions. Furthermore, this procedure discriminated against the formation of arylboronic acids homo-coupling byproducts. In addition, the preparation of the first aryl vinylsulfonate polymer, a material with functionalizable Michael acceptor sites, from a starting arylboronic acid was described. In the experiment, the researchers used many compounds, for example, (2,6-Dichloropyridin-4-yl)boronic acid (cas: 1072951-54-2HPLC of Formula: 1072951-54-2).

(2,6-Dichloropyridin-4-yl)boronic acid (cas: 1072951-54-2) 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. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. 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. HPLC of Formula: 1072951-54-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Reactions of Organomagnesates and Aryl Halides: Metalation and Nucleophilic Substitution was written by Farkas, Julius Jr.;Stoudt, Scott J.;Hanawalt, Erin M.;Pajerski, Anthony D.;Richey, Herman G. Jr.. And the article was included in Organometallics in 2004.Formula: C11H17N This article mentions the following:

Reactions with aryl halides (ArX) of preparations obtained in di-Et ether from an R₂Mg compound and a cryptand, an alkali-metal alkoxide, or tetrabutylammonium bromide lead to ArH and ArR. ArH results from magnesium-halogen exchange, and ArR results from aryne formation. Reactions of similar preparations with pyridine lead to formation of larger amounts of substitution product, and those with 2-cyclohexen-1-one to larger amounts of 1,4-addition product, than do reactions of R₂Mg alone. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0Formula: C11H17N).

4-Hexylpyridine (cas: 27876-24-0) 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. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. 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. Formula: C11H17N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Biosilica as an efficient heterogeneous catalyst for ipso-hydroxylation of arylboronic acids was written by Mahanta, Abhijit;Adhikari, Pooja;Bora, Utpal;Thakur, Ashim Jyoti. And the article was included in Tetrahedron Letters in 2015.HPLC of Formula: 51834-97-0 This article mentions the following:

A mild and efficient protocol for the conversion of arylboronic acids to phenol via ipso-hydroxylation was developed using aqueous hydrogen peroxide as oxidant and biosilica as heterogeneous catalyst. The recyclability of the catalyst is also evaluated and could be reused up to six consecutive cycles without a significant loss in catalytic activity. In the experiment, the researchers used many compounds, for example, 5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0HPLC of Formula: 51834-97-0).

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.HPLC of Formula: 51834-97-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Dual resonance functionality in pyridine 1-oxides. A double multinuclear NMR approach was written by Sawada, Masami;Takai, Yoshio;Yamano, Satoshi;Misumi, Soichi;Hanafusa, Terukiyo;Tsuno, Yuho. And the article was included in Journal of Organic Chemistry in 1988.Application In Synthesis of 3,5-Dimethylpyridine 1-oxide This article mentions the following:

Substituent effects on the nitrogen-15 NMR chem. shifts of 3- and 4-substituted pyridine 1-oxides in DMSO at natural abundance are reported for 26 derivatives A bilinear relationship is found between the ¹⁵N SCS (substituent chem. shift) of pyridine 1-oxides and the ¹³C SCS of the corresponding mono-substituted benzenes. Both the present ¹⁵N SCS data and the reported ¹⁷O SCS data of pyridine 1-oxides are analyzed by using the Ukawa-Tsuno’s LSFE and the Taft’s DSP LFER. The historically-accepted dual functionality of pyridine 1-oxides can be successfully expressed in terms of electron-donating and electron-accepting pi-electronic contributions by means of the LSFE treatment. The resulting internal consistency of the constant pi-electronic effect’s ratio, ρ_π⁺/ρ_π^– = 1.4, on the detecting nitrogen and oxygen is taken as evidence for justification of the dual functionality of the pyridinee 1-oxides and then, for rationalization of the LSFE treatment. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Application In Synthesis of 3,5-Dimethylpyridine 1-oxide).

3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) 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.Application In Synthesis of 3,5-Dimethylpyridine 1-oxide

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Antiparasitic agents. 3. Synthesis and anthelmintic activities of novel 2-pyridinyl-5-isothiocyanatobenzimidazoles was written by Haugwitz, R. D.;Maurer, B. V.;Jacobs, G. A.;Narayanan, V. L.;Cruthers, L.;Szanto, J.. And the article was included in Journal of Medicinal Chemistry in 1979.Recommanded Product: 1620-76-4 This article mentions the following:

The title compounds I (R¹ = H, Cl, O, Me, MeO, NCS; R² = H, Cl, or Me; R³ = H or NCS) were prepared and tested for anthelmintic activity in mice exptl. infected with Nematospiroides dubius (nematode) and Hymenolepis nana (Tapeworm), and in sheep naturally infected with gastrointestinal nematodes. The compounds were used at 0.2% in the mouse diet and at 50 mg/kg, orally in sheep. None of the compounds showed activity against N. dubius, 6 showed 100% activity against H. nana and 1-isothiocyanato-2-(2-pyridinyl)-1H-benzimidazole [71134-39-9] showed nematocidal activity in sheep. Maximum activity required attachment of SCN group at the 5(6) position. Structural activity relations are discussed. In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Recommanded Product: 1620-76-4).

4-Methylpicolinonitrile (cas: 1620-76-4) 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. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Recommanded Product: 1620-76-4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem