US4222967A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing bromine- and fluorine-containing halogenated hydrocarbons
Assignee: Kali Chemie AG
•
Filing: 1977-06-27
•
Granted: 1980-09-16
•
Expires: 1997-06-27
Abstract
Abstract A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons of formula (I) ##STR1## wherein R 1 represents hydrogen, fluorine, chlorine, bromine, lower alkyl, or at least partially fluorinated lower alkyl; R 2 represents hydrogen, fluorine, chlorine, or bromine; and, R 3 represents fluorine or perfluorinated lower alkyl, to form the corresponding compounds of formula (II) ##STR2## wherein R 1 , R 2 and R 3 are as defined above is disclosed. According to this process, compounds of formula (I) are reacted in gaseous form at relatively mild reaction conditions, e.g., reaction temperatures of between 100°-500° C. with hydrogen bromide in the presence of a catalyst comprising at least one component selected from the group consisting of (a) active carbon, (b) silica gel, (c) active alumina, and (d) a bromide of an element selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Zn, Cd, Cu, Ag, Al, Tl(I), Pb, Cr, Mn, Fe, Co, Ni, rare earth metals and metals of the platinum group.
Inventors
- 👤 Horst Boehm
- 👤 Karl-Heinz Hellberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:31
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/093; C07C17/20; C07C17/202; C07C17/206; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
114 words
A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons, which comprises the step of contacting a vapor phase mixture, comprising a halogenated fluorohydrocarbon compound selected from dichloro-difluoromethane, chloro-trifluoromethane or 2,2-dichloro-1,1,1-trifluoroethane, and hydrogen bromide, with a catalyst comprising a mixture of active carbon and at least one bromide of a metal selected from the group consisting of Zn, and Cd at a contact time and a reaction temperature of from about 100° C. to about 500° C. which is sufficient for substituting the chlorine in said halogenated fluorohydrocarbon compound by bromine to form (a) bromo-chloro-difluoromethane in the case of dichloro-difluoromethane, (b) bromo-trifluoromethane in the case of chloro-trifluoromethane, or (c) 2-bromo-2-chloro-1,1,1-trifluoroethane in the case of 2,2-dichloro-1,1,1-trifluoroethane.
Claim 2
Dependent Claim
114 words
A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons, which comprises the step of contacting a vapor phase mixture, comprising a halogenated fluorohydrocarbon compound selected from dichloro-difluoromethane, chloro-trifluoromethane or 2,2-dichloro-1,1,1-trifluoroethane, and hydrogen bromide, with a catalyst comprising a mixture of active carbon and at least one bromide of a metal selected from the group consisting of Zn, and Cd at a contact time and a reaction temperature of from about 100° C. to about 500° C. which is sufficient for substituting the chlorine in said halogenated fluorohydrocarbon compound by bromine to form (a) bromo-chloro-difluoromethane in the case of dichloro-difluoromethane, (b) bromo-trifluoromethane in the case of chloro-trifluoromethane, or (c) 2-bromo-2-chloro-1,1,1-trifluoroethane in the case of 2,2-dichloro-1,1,1-trifluoroethane.
Claim 3
Dependent Claim
13 words
The process as defined by claim 1, wherein bromo-chloro-difluoromethane is obtained from dichloro-difluoromethane.
Claim 4
Dependent Claim
13 words
The process as defined in claim 1, wherein bromo-trifluoromethane is obtained from chloro-trifluoromethane.
Claim 5
Dependent Claim
13 words
The process as defined in claim 1, wherein 2-bromo-2-chloro-1,1,-trifluoroethane is obtained from 2,2-dichloro-1,1,1-trifluoroethane.
Claim 6
Dependent Claim
140 words
A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons, which comprises the steps of: contacting a vapor phase mixture, comprising a halogenated fluorohydrocarbon compound selected from dichloro-difluoromethane or 2,2-dichloro-1,1,1-trifluoroethane, and hydrogen bromide, with a catalyst comprising a mixture of active carbon and at least one bromide of a metal selected from the group consisting of Zn, and Cd at a contact time and a reaction temperature of from about 100° C. to about 500° C. which is sufficient for substituting the chlorine in said fluorohydrocarbon compound by bromine, and continuously recycling a mixture of non-reacted starting material and a dibrominated reaction product into said contacting step, wherein said dibrominated reaction product is selected from (a) dibromo-difluoromethane obtained during the bromination of dichloro-difluoromethane, whereby bromo-chloro-difluoromethane is formed, and (b) 2,2-dibromo, 1,1,1-trifluoroethane obtained during the bromination of 2,2-dichloro-1,1,1-trifluoroethane, whereby 2-bromo-2-chloro-1,1,1-trifluoroethane is formed.
Claim 7
Dependent Claim
140 words
A process for brominating fluorine- and chlorine-containing halogenated hydrocarbons, which comprises the steps of: contacting a vapor phase mixture, comprising a halogenated fluorohydrocarbon compound selected from dichloro-difluoromethane or 2,2-dichloro-1,1,1-trifluoroethane, and hydrogen bromide, with a catalyst comprising a mixture of active carbon and at least one bromide of a metal selected from the group consisting of Zn, and Cd at a contact time and a reaction temperature of from about 100° C. to about 500° C. which is sufficient for substituting the chlorine in said fluorohydrocarbon compound by bromine, and continuously recycling a mixture of non-reacted starting material and a dibrominated reaction product into said contacting step, wherein said dibrominated reaction product is selected from (a) dibromo-difluoromethane obtained during the bromination of dichloro-difluoromethane, whereby bromo-chloro-difluoromethane is formed, and (b) 2,2-dibromo, 1,1,1-trifluoroethane obtained during the bromination of 2,2-dichloro-1,1,1-trifluoroethane, whereby 2-bromo-2-chloro-1,1,1-trifluoroethane is formed.
Claim 8
Dependent Claim
27 words
The process as defined in claim 5, wherein dibromo-difluoromethane which is obtained during the bromination of dichloro-difluoromethane is recycled into the reaction step, whereby bromo-chloro-difluoromethane is formed.
Claim 9
Dependent Claim
27 words
The process as defined in claim 5, wherein 2,2-dibromo-1,1,1-trifluoroethane which is obtained during the bromination of 2,2-dichloro-1,1,1-trifluoroethane is recycled into the reaction step, whereby 2-bromo-2-chloro-1,1,1-trifluoroethane is formed.
References Cited (Backward Citations)
US2553518A
Cited
US2729687A
Cited
US2875254A
Cited
US2921098A
Cited
US3000980A
Cited
US3370096A
Cited
US3755474A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |