144100-07-2Relevant articles and documents
C-H FLUORINATION OF HETEROCYCLES WITH SILVER (II) FLUORIDE
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Paragraph 00123, (2015/02/19)
The present invention provides compositions and methods for the selective C-H fluorination of nitrogen-containing heteroarenes with AgF2, which has previously been considered too reactive for practical, selective C-H fluorination. Fluorinated heteroarenes are prevalent in numerous pharmaceuticals, agrochemicals and materials. However, the reactions used to introduce fluorine into these molecules require pre-functionalized substrates or the use of F2 gas. The present invention provides a mild and general method for the C-H fluorination of nitrogen-containing heteroarene compounds to 2-fluoro-heteroarenes with commercially available AgF2. In various embodiments, these reactions occur at ambient temperature within one hour and occur with exclusive selectivity for fluorination at the 2-position. Exemplary reaction conditions are effective for fluorinating diazine heteroarenes to form a single fluorinated isomer.
Selective C-H fluorination of pyridines and diazines inspired by a classic amination reaction
Fier, Patrick S.,Hartwig, John F.
, p. 956 - 960 (2013/12/04)
Fluorinated heterocycles are prevalent in pharmaceuticals, agrochemicals, and materials. However, reactions that incorporate fluorine into heteroarenes are limited in scope and can be hazardous. We present a broadly applicable and safe method for the site-selective fluorination of a single carbon-hydrogen bond in pyridines and diazines using commercially available silver(II) fluoride. The reactions occur at ambient temperature within 1 hour with exclusive selectivity for fluorination adjacent to nitrogen. The mild conditions allow access to fluorinated derivatives of medicinally important compounds, as well as a range of 2-substituted pyridines prepared by subsequent nucleophilic displacement of fluoride. Mechanistic studies demonstrate that the pathway of a classic pyridine amination can be adapted for selective fluorination of a broad range of nitrogen heterocycles.
Microwave-accelerated fluorodenitrations and nitrodehalogenations: expeditious routes to labeled PET ligands and fluoropharmaceuticals
LaBeaume, Paul,Placzek, Michael,Daniels, Mathew,Kendrick, Ian,Ng, Patrick,McNeel, Melissa,Afroze, Roushan,Alexander, Abigail,Thomas, Rhiannon,Kallmerten, Amy E.,Jones, Graham B.
experimental part, p. 1906 - 1909 (2010/09/07)
Methods for the expeditious fluorination of arenes have been investigated, using readily available fluoride sources. An optimized procedure for microwave-accelerated fluorodenitration has been developed, giving good to excellent yields in less than 10 min, rendering it practical for use in the preparation of F18 labeled ligands for PET imaging. Application of the method in the synthesis of CNS agents is demonstrated, and a practical method for the preparation of substrates is also presented.
FLUORINATING AGENT AND METHOD FOR PRODUCING FLUORINE-CONTAINING COMPOUND USING SAME
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Page/Page column 13, (2008/06/13)
A method for producing a fluorine-containing organic compound represented by the formula (7): ????????R-Fm?????(7) wherein R represents a substituted or unsubstituted saturated hydrocarbon group, or a substituted or unsubstituted aromatic group and m represents an integer satisfying the inequality: 1≦m≦n, which comprises reacting a fluorinating agent represented by the formula (1): wherein R1 and R3 are the same or different, and represent an optionally substituted alkyl group, R2, R4 and R5 are the same or different, and represent a hydrogen atom or an optionally substituted alkyl group, x satisfies 0- represents a monovalent anion other than a fluoride ion, with an organic compound of the formula (6): ????????R-Ln?????(6) wherein R is the same as defined above, L represents a leaving group and n represents an integer of 1 or more, and a fluorinating agent using the same are described.
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.
2-Fluoropyridines, their preparation and their use in liquid crystal mixtures
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, (2008/06/13)
2-Fluoropyridines, processes for their preparation and their use in ferroelectric liquid crystal mixtures A 2-fluoropyridine of the formula (I) STR1 in which the symbols have the following meaning: R1, R2, independently of one another, are, for example, H or straight-chain or branched alkyl, A1, A2, A3, A4, identical or different, are, for example, 1-phenylene, pyrazine-2,5-diyl or trans-1,4-cyclohexylene, M1, M2, M3, M4, identical or different, are, for example, --O-- or --CO--O--, R3, R4, R6, R7, independently of one another, are, for example, H or straight-chain or branched alkyl, M5 is, for example, --O--CO-- or a single bond, k, l, m, n, o, p, q, r are zero or one, with the proviso that the sum of k+m+p+r is less than 4 and greater than zero, can advantageously be used as a component in ferroelectric liquid crystal mixtures.
