Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1990-07-03
1991-12-17
Rotman, Alan L.
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
203DIG6, 546346, B01D 300, C07D21326
Patent
active
050736370
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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Little John C.
Wilson Charles A.
Davey Merlin B.
Osbourne D. Wendell
Rotman Alan L.
The Dow Chemical
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