14529-53-4Relevant articles and documents
Preparation method of ortho-alkoxy substituted pyridine compound
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Paragraph 0061-0062, (2021/09/08)
The invention provides a preparation method of an ortho-alkoxy substituted pyridine compound, the preparation method comprises the following step: reacting an ortho-amino substituted pyridine compound with an ortho-formate compound in the presence of a nitrite compound to generate the ortho-alkoxy substituted pyridine compound. The method has the advantages of high efficiency, low cost, environmental protection and the like.
Novel synthesis method for ortho-alkane superseded pyridine
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Paragraph 0018; 0019; 0020; 0021, (2017/07/19)
The invention relates to a novel synthesis method for ortho-alkane superseded pyridine. According to the method, ortho halogenated pyridine serves as raw materials, the ortho halogenated pyridine and corresponding alcohol react to obtain the ortho-alkane superseded pyridine under the action of sodium hydroxide. The reaction has universality for the ortho halogenated pyridine, and the method is simple and practical. Influence of consumption of the sodium hydroxide on mono-substitution and di-substitution in the reaction is inspected, alkoxy mono-substitution products and alkoxy di-substitution production are acquired, and a novel simply-operated, economical and favorable process for synthesis ortho-alkane superseded pyridine is provided.
A Novel Convenient Synthesis of Pyridinyl and Quinolinyl Triflates and Tosylates via One-Pot Diazotization of Aminopyridines and Aminoquinolines in Solution
Kassanova, Assiya Zh.,Krasnokutskaya, Elena A.,Beisembai, Perizat S.,Filimonov, Victor D.
, p. 256 - 262 (2016/01/15)
The first effective and simple method for the direct one-pot transformation of 2-, 3-, and 4-aminopyridines, 2,6-diaminopyridines, and 2-aminoquinoline into the corresponding pyridinyl and quinolinyl trifluoromethanesulfonates and tosylates in solvents was developed. The procedure involves diazotization of the heterocyclic amines with sodium nitrite in mixed hexane-DMSO or hexane-DMF solutions in the presence of trifluoromethanesulfonic acid or p-toluenesulfonic acid.
NaBH4-TMEDA and a palladium catalyst as efficient regio- and chemoselective system for the hydrodehalogenation of halogenated heterocycles
Chelucci, Giorgio,Figus, Susanna
, p. 191 - 209 (2014/07/21)
The pair NaBH4-TMEDA as hydride source and a palladium catalyst in THF prove to be an efficient system for the hydrodehalogenation of halogenated heterocycles with one or more heteroatoms. In general, Pd(OAc) 2-PPh3 rapidly hydrodehalogenates reactive halo-heterocycles such as bromo-pyridines, -quinolines, -thiophenes, -indoles, -imidazoles, etc., at room temperature in very good yields, whereas in most cases PdCl2(dppf) reduces less reactive halides such as chloro-pyridines, -quinolines, -pyrimidines and bromo-indoles, -benzofurans, etc. Moreover, PdCl2(tbpf) shows to be even more active removing the 2- and 5-chlorine from both thiophene and thiazole rings. The reaction conditions tolerate various functional groups, allowing highly chemoselective reactions in the presence of halide, ester, alkyne, alkene and nitrile substituents. Moreover, with a proper selection of the catalyst it is also possible to obtain a good control in the regioselective hydrodehalogenation of a variety of polyhalogenated substrates.
Hydrodehalogenation of halogenated pyridines and quinolines by sodium borohydride/N,N,N′,N′-tetramethylethylenediamine under palladium catalysis
Chelucci, Giorgio
experimental part, p. 1562 - 1565 (2010/06/14)
A protocol for the hydrodehalogenation of halogenated pyridines and quinolines by the sodium borohydride/N,N,N′,N′-tetramethylethylenediamine (NaBH4-TMEDA) system under palladium catalysts is reported. Catalytic amounts of [1,1′-bis(diphenylphosphino)ferrocene] dichloropalladium(II) in combination with NaBH4-TMEDA rapidly hydrodehalogenate chloro(bromo)-pyridines and -quinolines at room temperature in quantitative yields. Chemoselective reduction of 4,7-dichloroquinoline affords 7-chloroquinoline as the sole product in almost quantitative yield. Moreover, palladium(II) acetate-triphenylphosphine and NaBH4-TMEDA are able to reduce efficiently reactive bromo-pyridines and -quinolines.
Microwave-assisted silver(I)-mediated selective O-alkylation of aromatic imidate systems
Singh, Brajendra K.,Cavalluzzo, Claudia,De Maeyer, Marc,Debyser, Zeger,Parmar, Virinder S.,Van Der Eycken, Erik
experimental part, p. 2725 - 2728 (2010/01/21)
A novel microwave-assisted protocol has been developed for the selective O-alkylation of aromatic imidate systems with various halides under microwave irradiation using silver carbonate as the base. Products were obtained in short reaction time and in excellent yields. Georg Thieme Verlag Stuttgart.
On the thermally induced rearrangement of 2-alkoxypyridines to N-alkylpyridones
Lister, Troy,Prager, Rolf H.,Tsaconas, Michael,Wilkinson, Kerry L.
, p. 913 - 916 (2007/10/03)
Analogues of 2-methoxypyridine undergo rearrangement to N-methylpyridones under flash vacuum pyrolysis (FVP) conditions. Ethoxy derivatives undergo competitive ethyl migration and elimination of ethylene. Analogues of 4-methoxypyridine do not undergo rearrangement under FVP conditions, but demethylation on silica may occur. The ease of rearrangement follows the basicity of the alkoxyhetarene to some extent. The vapour-phase rearrangements have been contrasted to condensed-phase pyrolyses. and a four-centre transition state for the former is supported by computation. The rearrangement allows structural assignment to the two products from the reaction of 2,4-dichloroquinoline with pyrrolidine.
Elemental fluorine. Part 10.1 Selective fluorination of pyridine, quinoline and quinoxaline derivatives with fluorine-iodine mixtures
Chambers, Richard D.,Parsons, Mandy,Sandford, Graham,Skinner, Christopher J.,Atherton, Malcolm J.,Moilliet, John S.
, p. 803 - 810 (2007/10/03)
Selective fluorination of a range of pyridine and quinoline substrates to give corresponding 2-fluoro-derivatives can be readily achieved in high yield at room temperature using elemental fluorine-iodine mixtures. Reaction of fluorine with iodine forms, in situ, systems that function like sources of both iodonium and fluoride ions and fluorination of heterocyclic derivatives is suggested to proceed by fluoride ion attack on intermediate W-iodo-heterocyclic species. Quinoxaline derivatives react under similar conditions to give either the 2-fluoro- or 2,3-difluoro-quinoxaline derivatives depending on the ratio of fluorine passed through the solution. In related processes, pyridine can be alkoxylated upon reaction of an appropriate alcohol and fluorine.
Selective alkylation of 2-pyridone in solvent-free conditions
Almena,Diez-Barra,de la Hoz
, p. 1057 - 1063 (2007/10/02)
Alkylation of 2-pyridone has been performed in solvent-free conditions. The effect of base, phase transfer agent, and alkylation agent has been discussed.
Copper(I) Halide Catalysed Synthesis of Alkyl Aryl and Alkyl Heteroaryl Ethers
Keegstra, Menno A.,Peters, Theo H. A.,Brandsma, Lambert
, p. 3633 - 3652 (2007/10/02)
A number of alkyl aryl and alkyl heteroaryl ethers have been prepared from (hetero) aryl halides (mainly bromides) and sodium alkoxides, using copper(I)bromide as a catalyst.The influence of the main solvent, the halogen atom, reaction temperature and the presence of oxygen upon the rate and selectivity has been studied.Furthermore the decomposition of the catalyst and the reduction of the aryl halide are studied.
