Process for cis-1-chloro-3,3,3-trifluoropropene
View Patent ↗Disclosed is a process for the preparation of cis-1-chloro-3,3,3-trifluoropropene (cis-1233zd) comprising the steps of (a) providing CF 3 CHClCHCl 2 (233da), and (b) treating the 233da with a dechlorinating agent to produce a mixture of compounds including cis-1-chloro-3,3,3-trifluoropropene, preferably wherein the amount of the cis-isomer generated in the reaction is not less than 30%.
1. A process for the preparation of cis-1-chloro-3,3,3-trifluoropropene comprising the steps of (a) providing CF 3 CHClCHCl 2 (HCFC 233da), and (b) treating the HCFC 233da with a dechlorinating agent to produce a mixture of compounds including up to 48% by weight of cis-1-chloro-3,3,3-trifluoropropene (cis-1233zd).
2. The process of claim 1 , wherein the compound cis-1-chloro-3,3,3-trifluoropropene is isolated from the mixture of compounds produced in the process.
3. The process of claim 1 , wherein the dechlorinating agent is selected from the group consisting of zinc, zinc compounds, a mixture of zinc compounds, copper, magnesium, and a zinc/copper alloy, and mixtures thereof.
4. The process of claim 3 , wherein the dechlorinating agent comprises zinc dust.
5. The process of claim 3 , wherein the dechlorinating agent comprises a zinc-copper alloy.
6. The process of claim 5 , wherein the zinc-copper alloy dechlorinating agent comprises a mixture of zinc dust and cuprous iodide.
7. The process of claim 1 , wherein a solvent is used in the process.
8. The process of claim 7 , wherein the solvent is selected from the group consisting of alcohols, ethers, amides, carboxylic acids, water, and mixtures thereof.
9. The process of claim 8 , wherein the solvent comprises water.
10. The process of claim 1 , further comprising the use of a catalyst.
11. The process of claim 10 , wherein the catalyst is selected from the group consisting of mineral acids and mixtures thereof.
12. The process of claim 11 , wherein the mineral acid catalyst comprises HCl.
13. The process of claim 10 , wherein the catalyst is selected from the group consisting of the Lewis acids and mixtures thereof.
14. The process of claim 13 , wherein the Lewis acid catalyst comprises a metal salt or mixture of metal halide salts.
15. The process of claim 14 , wherein the metal salt comprises a zinc halide salt.
16. The process of claim 15 , wherein the zinc halide salt comprises zinc chloride.
17. The process of claim 14 , wherein the metal salt comprises a tin halide salt.
18. The process of claim 17 , wherein the tin halide salt comprises tin chloride.
19. The process of claim 7 , wherein the reaction temperature range is less than the boiling point of the solvent.
20. A process for the preparation of cis-1-chloro-3,3,3-trifluoropropene (1233zd(Z)) comprising the steps of:
(a) mixing a combination comprising zinc, solvent, and catalyst;
(b) heating the mixture to within a few degrees of the predetermined reaction temperature;
(c) adding 233da to the heated mixture in step (b) in a manner that controls the reaction temperature;
(d) running the reaction and adding 233da as need; and
(e) collecting the 1233zd(Z) as it is produced at a yield of up to about 48% by weight.
21. The process of claim 20 , wherein the 233da is added mechanically at a set rate that is slow enough to maintain the reaction temperature.
22. The process of claim 20 , wherein the reaction heating is continued for a time to ensure that all the 233da has reacted.