- Preparation method of 4-aminopyridine compound
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The invention discloses a preparation method of a 4-aminopyridine compound. The preparation method comprises the following steps: adding a 4-amino- 3-chloropyridine compound or a 4-amino-3, 5-dichloropyridine compound, potassium phosphate and a catalyst into a solvent, and reacting at 0-10 MPa and 0-100 DEG C for 4-12 hours. According to the preparation method of the 4-aminopyridine compound, therelated raw materials are easy to obtain or self-make, the cost is low, the preparation method is simple, the reaction efficiency is high, the raw material cost is low, and byproducts have economic value; meanwhile, the reaction involved in the invention has good universality and tolerance to functional groups.
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- PHOSPHAZENIUM SALT MIXTURES CONTAINING HEXAKIS(AMINO)DIPHOSPHAZENIUM, TETRAKIS(AMINO)-PHOSPHONIUM AND POLYAMINOPHOSPAZENIUM SALTS
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The invention relates to mixtures containing 5 99.5 wt. % of a compound of formula (I), 95 0.5 wt. % of a compound of formula (II) and a maximum of 10 wt. % of one of several compounds of general formula (III a), wherein A - A which are independent from each other are equal or different and represent a straight-chained or branched alkyl or alkenyl having 1 - 12 carbon atoms, cycloalkyl having 4 8 carbon atoms, an aryl having 6 -12 carbon atoms, an aralkyl having 7 - 12 carbon atoms, or A-A, A-A, A-A etc. - A-A which are independent from each other and are equal or different and are connected together directly or via O or N-A to a ring having 3 - 7 ring members, A represents an alkyl having 1 - 4 carbon atoms. X1 and/or X2 and/or X3 which are independent from each other represent a radical of formula (III b), or the radical X1 and/or X2 and/or X3 as well as a straight-chained or branched alkyl or alkenyl having 1 - 12 carbon atoms, cycloalkyl having 4 - 8 carbon atoms represent an aryl having 6 - 12 carbon atoms, an aralkyl having 7 - 12 carbon atoms, or respectively the radicals which are disposed on an identically bound nitrogen atom, e.g. A and A, A and A, A and A etc. - A and A which are independent from each other are equal or different and are connected together directly or via O or N-A to a ring having 3 - 7 ring members and A represents an alkyl having 1 - 4 carbon atoms and B represents a single-valent organic or inorganic acid radical or the equivalent of a multi-valent acid radical. The mixtures can be used as catalysts and co-catalysts for phase transfer reactions, nucleophilic substitution reactions or halogen-fluoro-exchange reactions.
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Page/Page column 13-14
(2010/02/08)
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- METHOD FOR PRODUCING A COMPOUND CONTAINING FLUORINE VIA FLUORINE-HALOGEN EXCHANGE BY SPECIAL POLYAMINO PHOSPHAZENE CATALYSTS
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The invention relates to a method for producing compounds containing fluorine by reacting a compound, which contains hydrogen that can be exchanged for fluorine, with a fluoride or with a mixture of fluorides of general formula (I): MeF, wherein Me represents an alkaline earth metal ion, an NH4+ ion or an alkali metal ion, in the presence or absence of a solvent at a temperature ranging from 60 to 260 °C. The invention is characterized in that the reaction is carried out in the presence of a compound or of a mixture of compounds of general formula (IIa) and/or (IIb), whereby X1 and/or X2 and/or X3, independent of one another, have groups of formula (llc) or other groups cited in the claims.
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- Preparation and reactions of 2,3,4,6-tetrafluoropyridine and its derivatives
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A reliable route to 2,3,4,6-tetrafluoropyridine has been established starting from the readily available 3,5-dichlorotrifluoropyridine by halogen exchange under controlled conditions to give 3-chlorotetrafluoropyridine and its subsequent hydrodechlorination using hydrogen over palladium on alumina at 250-270°C. The formation and reactions of the 3-lithio derivative have been studied with the aim of obtaining 3,4-disubstituted trifluoropyridines. Routes to such materials have been developed and their conversion to deazapurine derivatives as potential substrates for the generation of anti-sense nucleosides are reported.
- Coe, Paul L.,Rees, Anthony J.
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- POLYHALOAROMATIC EQUILIBRATIONS
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Chromium oxide is a good catalyst for scrambling halogens among polyhaloaromatic compounds.Chloropentafluorobenzene and bromopentafluorobenzene disproportionate to hexafluorobenzene and the respective tetrafluorodihalobenzenes.Pentachloro- and pentafluoropyridines produce pyridines with intermediate numbers of both types of halogens.Cyano, trifluoromethyl and a single hydrogen can be present on the aromatic rings without interfering with the chemistry.
- Weigert, F. J.
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- Gas-phase Photoisomerization of 3-Chloro-2,4,5,6-tetrafluoropyridine
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Continuous photolysis of 3-chloro-2,4,5,6-tetrafluoropyridine produced the isomer which underwent rearomatization to the parent molecule when heated in the gas-phase.Evidence from UV absorption spectroscopy and mass spectrometry indicated that this product was the Dewar pyridine.
- Sztuba, Barbara
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p. 577 - 581
(2007/10/02)
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