Process for synthesis of fluorinated olefins
Disclosed is a process for the synthesis of fluorinated olefins, and in particularly preferred embodiments tetrafluorinated olefins having F on an unsaturated, non-terminal carbon, such as 2,3,3,3-tetrafluoropropene. The preferred processes of the present invention in accordance with one embodiment generally comprise: (a) reacting a compound of formula (I) X 1 X 2 (I) with a compound of formula (II) CX 1 X 2 X 3 CX 1 ═CX 1 X 2 (II) to produce a reaction product comprising a compound of formula (III) CF 3 CHX 1 CH 2 X 2 (III), and (b) exposing said compound of formula (III) to reaction conditions effective to convert said compound of formula (III) to a compound of formula (IV) CF 3 CZ═CH 2 (IV) wherein X 1 , X 2 , and X 3 are each independently selected from the group consisting of hydrogen, chlorine, bromine, fluorine and iodine, provided that X 1 and X 2 in formula (I) are not both hydrogen and Z is Cl, I, Br, or F.
1 . A process for the synthesis of 2-halo-3,3,3-fluoropropene comprising:
(a) providing a reaction product comprising CF 3 CClFCH 3 (HFC-244bb), wherein said providing step (a) comprises reacting HF with CF 3 CCl═CH 2 at a temperature of from about 0° C. to about 250° C. in the presence of a catalyst, and
(b) exposing said CF 3 CClFCH 3 (HFC-244bb) to reaction conditions effective to convert said CF 3 CClFCH 3 (HFC-244bb) to a compound of formula (IV)
CF 3 CZ═CH 2 (IV),
wherein Z is F.
2 . The process of claim 1 wherein in said exposing step (b) said reaction conditions comprise a catalyzed liquid phase reaction.
3 . The process of claim 2 wherein said catalyst of said exposing step comprises SbCl 5 .
4 . The process of claim 1 wherein said exposing step (b) is a liquid phase reaction that involves contacting said CF 3 CClFCH 3 (HFC-244bb) with a potassium hydroxide solution and, optionally, a Crown ether.
5 . The process of claim 4 wherein said exposing step is at least partially conducted at a temperature of from about 25° C. to about 90° C. and at a pressure of about 100 to about 200 psig.
6 . The process of claim 1 wherein said exposing step (b) is a vapor phase reaction that involves contacting said CF 3 CClFCH 3 (HFC-244bb) with a metal-based catalyst.
7 . The process of claim 6 wherein said metal-based catalyst is at least one of Pd or Ni on a carbon substrate.