Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1989-01-23
1990-11-27
Rotman, Alan L.
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
546346, 203 28, 203 29, C07D21326, C07D21361, B01D 334
Patent
active
049736981
ABSTRACT:
2,3-Difluoro-5-(trifluoromethyl)pyridine is prepared by contacting a 2,3-dihalo-5-(trifluoromethyl) pyridine with an effective amount of KF or CsF in a polar aprotic solvent (diluent) at an elevated temperature under substantially anhydrous conditions with removal of the difluoropyridine products essentially as they are formed. The starting material may optionally be added as the reaction proceeds to minimize decomposition. The reaction is also optionally conducted in the presence of an acid scavenger and/or a crown ether or other phase-transfer catalyst.
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Abramovitch, Pyridine and its Derivatives, Supplement Part 2, pp. 422-423.
Little John C.
Wilson Charles A.
Davey Herlin B.
Osborne D. Wendell
Rotman Alan L.
The Dow Chemical Company
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