Claims
- 1. A process for the preparation of 3-chloro-4,5-difluoro-benzonitrile which comprises the steps of
- (a) reacting an alkali metal fluoride with 4-chloro-3,5-dinitrobenzonitrile at a temperature of from about 50.degree. to about 300.degree. Celsius to form 4-fluoro-3,5-dinitro-benzonitrile;
- (b) chlorodenitrating the 4-fluoro-e,5-dinitro product of step (a) to form 3,5-dichloro-4-fluorobenzonitrile; and
- (c) reacting the 3,5-dichloro-4-fluorobenzonitrile compound prepared in step (b) at a temperature of from about 50.degree. to about 300.degree. Celsius with an alkali metal fluoride to form 3-chloro-4,5-difluorobenzonitrile.
- 2. A process according to claim 1, wherein the alkali metal fluoride of steps (a) and (b) is potassium fluoride.
- 3. A process according to claim 1, wherein the reactions of steps (a) and (c) are carried out neat at a temperature of 140.5.degree. to about 155.degree. Celsius for the reaction of step (a) and about 170.degree. to about 270.degree. Celsius for the reaction of step (c).
- 4. A process according to claim 1, wherein the reactions of steps (a) and (c) are carried out in the presence of a solvent at a temperature of about 75.degree. to about 155.degree. Celsius for the reaction of step (a) and about 170.degree. to about 270.degree. Celsius for the reaction of step (c).
- 5. A process according to claim 1, wherein the reaction of step (a) is carried out neat at a temperature of about 75.degree. to about 155.degree. Celsius in the presence of a solvent and the reaction of step (c) is carried out neat at a temperature of about 170.degree. to about 270.degree. Celsius.
- 6. A process according to claim 1, wherein the reaction of step (a) is carried out neat at a temperature of about 140.5.degree. to about 155.degree. Celsius in the presence of a solvent and the reaction of step (c) is carried out neat at a temperature of about 170.degree. to about 270.degree. Celsius.
- 7. A process according to claim 1, wherein the chlorodenitration reaction of step (b) is carried out in the vapor phase at a temperature of about 250.degree. to about 450.degree. Celsius.
- 8. A process according to claim 7, wherein the chlorodenitration reaction of step (b) is carried out in the vapor phase by reacting Cl.sub.2 with 4-fluoro-3,5-dinitrobenzonitrile at a temperature of about 290.degree. to about 410.degree. Celsius.
- 9. A process for the preparation of 3-chloro-4,5-difluorobenzonitrile which comprises reacting 3,5-dichloro-4-fluoro-benzonitrile with an alkali metal fluoride at a temperature of from about 50.degree. to about 300.degree. Celsius.
REFERENCE TO PRIOR APPLICATION
This is a continuation of application Ser. No. 825,505, filed Feb. 3, 1986, now abandoned, which is a continuation-in-part of application Ser. No. 660,765, filed Oct. 15, 1984 now U.S. Pat. No. 4,590,315.
US Referenced Citations (5)
Continuations (1)
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825505 |
Feb 1986 |
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Continuation in Parts (1)
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660765 |
Oct 1984 |
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