Process for making fluorophthalimides
AssigneeAlbemarle Corporation
InventorsStephen E. Belmont, Charles R. Everly, Yunqi Liu
Life of this patent
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Abstract
Tri- or tetrafluorophthalimides are produced in a halogen-exchange reaction utilizing a metal fluoride salt and a dihydrocarbyl sulfoxide as the solvent. No phase-transfer catalyst is employed. The process has been found capable of producing the fully fluorinated phthalimide in yields of over 90% GC in reactions performed at 135-155 ° C. in reaction periods of as little as one hour even though no phase-transfer catalyst is employed.
Claims27
A process which comprises:
- a) forming a phase-transfer catalyst-free reaction mixture comprised of (1) a tri- or tetrahalophthalimide in which at least one aromatic carbon atom in the molecule is substituted by a non-fluorine halogen atom, (2) a metal fluoride salt, (3) an inert hydrocarbyl sulfoxide solvent;
- and
- b) maintaining said mixture at one or more temperatures in the range of about 135° C. to about 185° C. such that a compound is produced in which each non-fluorine halogen of the halophthalimide of a) which is attached to an aromatic carbon atom is replaced by a fluorine atom.
A process which comprises heating a reaction mixture formed from ingredients comprising (1) a tri- or tetrahalophthalimide in which at least one aromatic carbon atom is substituted by a non-fluorine halogen atom, (2) a metal fluoride salt, and (3) a hydrocarbyl sulfoxide solvent, said mixture being devoid of a phase-transfer catalyst, at a temperature in the range of about 135° C. to about 185° C. to produce a fluorophthalimide in which each non-fluorine halogen atom of the halophthalimide which is attached to an aromatic carbon is replaced by a fluorine.
Dependencies are inferred from the claim text.