Claims
- 1-3. (canceled)
- 4. A method of preparing a mixture of a p-bromophenol and a p-benzoquinone, said method comprising contacting in a reaction mixture a hydroxyaromatic compound with:
(a) hydrogen bromide; (b) at least one source of copper selected from the group consisting of copper compounds, and elemental copper: and (c) oxygen gas; said hydrogen bromide being present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of said hydroxyaromatic compound, said contacting taking place at a temperature ranging from about 20° C. to about 250° C. and carried out under pressure, said pressure ranging from about 1 atm to about 140 atm.
- 5. The method according to claim 4 wherein said oxygen gas is present as a mixture with nitrogen gas or as air or as an oxygen-enriched air mixture.
- 6-8. (canceled)
- 9. A method of preparing a mixture of a p-bromophenol and a p-benzoquinone, said method comprising contacting in a reaction mixture a hydroxyaromatic compound with:
(a) hydrogen bromide: (b) at least one source of copper selected from the group consisting of copper compounds, and elemental copper; (c) oxygen gas; and (d) water in an amount ranging from about 0.4 moles to about 5 moles of water per mole of said hydroxyaromatic compound; said hydrogen bromide being present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of said hydroxyaromatic compound, said contacting taking place at a temperature ranging from about 20° C. to about 250° C.
- 10. A method of preparing a mixture of a p-bromophenol and a p-benzoquinone, said method comprising contacting in a reaction mixture a hydroxyaromatic compound with:
(a) aqueous hydrogen bromide; (b) at least one source of copper selected from the group consisting of copper compounds, and elemental copper; and (c) oxygen gas: said aqueous hydrogen bromide being present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of said hydroxyaromatic compound, said contacting taking place at a temperature ranging from about 20° C. to about 250° C.
- 11-13. (canceled)
- 14. A method for the preparation of 4-bromophenol as a mixture with 1,4-benzoquinone, said method comprising contacting in a reaction mixture at a temperature ranging from about 20° C. to about 150° C., phenol with:
(a) aqueous hydrogen bromide; (b) at least one source of copper selected from the group consisting of cupric bromide or cuprous bromide; (c) acetonitrile; and (d) oxygen gas; said aqueous hydrogen bromide being present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of phenol, said source of copper being present in an amount ranging from about 0.01 to about 0.20 moles of copper per mole of phenol, said acetonitrile being present in an amount ranging from about 0.01 to about 1.0 liters of acetonitrile per mole of phenol, said contacting being carried out under a partial pressure of oxygen ranging from about 1 to about 140 atm.
- 15. The method according to claim 14 wherein said phenol is converted to said 4-bromophenol and said 1,4-benzoquinone to the extent of at least 20 percent.
- 16. The method according to claim 14 further comprising a separation step, said separation step comprising transforming said mixture comprising said 4-bromophenol and said 1,4-benzoquinone into purified 4-bromophenol having a purity of at least 90 percent, and purified 1,4-benzoquinone having a purity of at least 90 percent.
- 17. A method for the preparation of 4-bromo-2-methylphenol as a mixture with 2-methyl-1,4-benzoquinone, said method comprising contacting in a reaction mixture at a temperature ranging from about 20° C. to about 150° C., o-cresol with:
(a) aqueous hydrogen bromide; (b) at least one source of copper selected from the group consisting of cupric bromide or cuprous bromide; (c) acetonitrile; and (d) oxygen gas; said aqueous hydrogen bromide being present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of o-cresol, said source of copper being present in an amount ranging from about 0.01 to about 0.20 moles of copper per mole of o-cresol, said acetonitrile being present in an amount ranging from about 0.01 to about 1.0 liters of acetonitrile per mole of o-cresol, and said contacting being carried out under a partial pressure of oxygen ranging from about 1 to about 140 atm.
- 18. A method for preparing a mixture of a p-bromophenol and a 1,4-hydroquinone derivative, said method comprising:
(a) contacting in a reaction mixture a hydroxyaromatic compound with hydrogen bromide, oxygen gas, and at least one source of copper selected from the group consisting of copper compounds and elemental copper at a temperature ranging from about 20° C. to about 250° C., wherein said hydrogen bromide is present in an amount corresponding to less than 0.2 moles of hydrogen bromide per mole of said hydroxyaromatic compound, to produce a product mixture comprising said p-bromophenol, a 1,4-benzoquinone derivative, and said copper catalyst; (b) adding additional hydrogen bromide and water to said product mixture of step (a) to produce an aqueous phase comprising said copper catalyst, unreacted hydrogen bromide, and water, and an organic phase comprising said p-bromophenol and said 1,4-benzoquinone derivative, followed by the step of separating said aqueous phase from said organic phase; and (c) contacting said separated organic phase with a metal catalyst and hydrogen gas to produce a resulting mixture comprising said p-bromophenol and said 1,4-hydroquinone derivative.
- 19. The method according to claim 18 wherein said hydroxyaromatic compound has structure I
- 20. The method according to claim 19 wherein said hydroxyaromatic compound is phenol, and wherein said p-bromophenol is 4-bromophenol, and said 1,4-hydroquinone derivative is 1,4-hydroquinone.
- 21. The method according to claim 19 wherein said hydroxyaromatic compound is o-cresol, and wherein said p-bromophenol is 4-bromo-2-methylphenol, and said 1,4-hydroquinone derivative is 2-methyl-1,4-hydroquinone.
- 22. The method according to claim 18 wherein said at least one source of copper is present in an amount sufficient to provide copper ion to the reaction mixture in an amount ranging from about 0.001 to about 0.200 moles of copper ion per mole of hydroxyaromatic compound.
- 23. The method according to claim 18 wherein said copper compounds are selected from the group consisting of cuprous chloride, cuprous bromide, cuprous iodide, cupric chloride, cupric bromide, and cupric iodide.
- 24. The method according to claim 18 wherein said contacting in step (a) is carried out under pressure ranging from about 1 atm to about 140 atm.
- 25. The method according to claim 18 wherein said reaction mixture and said product mixture further comprise an organic solvent selected from the group consisting of acetonitrile, propionitrile, butyronitrile, isopropylnitrile, benzonitrile, and mixtures thereof, and wherein prior to step (b), at least a portion of said organic solvent is optionally removed from said product mixture.
- 26. The method according to claim 18 wherein said reaction mixture further comprises water in an amount corresponding to about 0.4 moles to about 5 moles of water per mole of said hydroxyaromatic compound.
- 27. The method of claim 18 wherein said hydrogen bromide is aqueous hydrogen bromide.
- 28. The method according to claim 18 wherein said metal catalyst comprises palladium or nickel.
- 29. The method according to claim 18 further comprising the step of recycling at least a portion of said aqueous phase comprising said copper catalyst and unreacted hydrogen bromide to a further method for preparing a mixture of a p-bromophenol and a 1,4-hydroquinone derivative, wherein a portion of water has optionally been removed from said aqueous phase prior to recycling.
- 30. The method according to claim 18 further comprising prior to step (c) the steps of:
(i) washing said separated organic phase with water at least one time to remove any traces of unreacted hydrogen bromide and any traces of said copper catalyst; (ii) removing said wash water from said separated organic phase; (iii) combining said wash water with said aqueous phase comprising said copper catalyst and unreacted hydrogen bromide, and optionally removing a portion of water from said combined aqueous phase and wash water; and (iv) recycling said combined aqueous phase and wash water, wherein a portion of water has optionally been removed, to a further method for preparing a mixture of a p-bromophenol and a 1,4-hydroquinone derivative.
- 31. The method according to claim 18 further comprising a separation step, said separation step comprising transforming said mixture comprising said p-bromophenol and said 1, 4-hydroquinone derivative into a purified p-bromophenol having a purity of at least 90 percent, and a purified 1, 4-hydroquinone derivative having a purity of at least 90 percent.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Application is a continuation-in-part of Ser. No. 10/406,061 filed Apr. 4, 2003, entitled “METHOD OF PREPARING MIXTURES OF BROMOPHENOLS AND BENZOQUINONES”, now U.S. Patent No.______ issued ______, which is hereby incorporated by reference herein in its entirety.
[0002] This Application is related to the following U.S. Patent Application/Patent:
[0003] U.S. Ser. No. 10/342,475, filed Jan. 16, 2003, entitled “BROMINATION OF HYDROXYAROMATIC COMPOUNDS AND FURTHER CONVERSION TO DIHYDROXYAROMATIC COMPOUNDS”, now U.S. Patent No.______ issued ______, which is hereby incorporated by reference herein in its entirety.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10406061 |
Apr 2003 |
US |
Child |
10704002 |
Nov 2003 |
US |