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 2,3,3,3-tetrafluoropropene comprising:
(a) reacting hydrogen fluoride (HF) at a temperature of from about 0° C. to about 250° C. and at a pressure of from about 500 to about 1000 psig with a compound of formula (IIA)
CH 2 X 2 CX 2 ═CX 2 X 2 (IIA)
to produce an intermediate reaction product comprising from about 40 wt. % to about 70 wt. % CF 3 CHFCH 2 F, and
(b) exposing at least a portion of said intermediate reaction product to reaction conditions effective to convert at least a portion of said CF 3 CHFCH 2 F to a compound of formula (IV)
CF 3 CZ═CH 2 (IV)
wherein each X 2 is independently selected from the group consisting of hydrogen, chlorine, bromine, fluorine and iodine, Z is F wherein said exposing step (b) comprises a liquid phase reaction or a vapor phase reaction, wherein the liquid phase reaction comprises contacting at least a portion of said CF 3 CHFCH 2 F with a potassium hydroxide solution and wherein the vapor phase reaction comprises contacting at least a portion of said CF 3 CHFCH 2 F with at least one metal-based catalyst selected from the group consisting of Ni-mesh, Ni/C, Cr 2 O 3 , activated carbon, Pd/C, and FeCl 3 .
2. The process of claim 1 wherein said intermediate reaction product further comprises a compound of formula (III)
CF 3 CHX 1 CH 2 X 2 (III),
wherein X 1 and X 2 are each independently selected from the group consisting of hydrogen, chlorine, bromine, fluorine and iodine, and wherein the compound is not CF 3 CHFCH 2 F.
3. The process of claim 1 wherein said compound of formula (IIA) is CH 2 ClCCl═CCl 2 .
4. The process of claim 1 wherein said reacting step (a) is a catalyzed liquid phase reaction.
5. The process of claim 1 wherein said catalyst comprises SbCl 5 .
6. The process of claim 1 wherein said exposing step (b) is a liquid phase reaction that involves contacting at least a portion of said CF 3 CHFCH 2 F with a potassium hydroxide solution and, optionally, a Crown ether.
7. The process of claim 6 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.
8. The process of claim 1 wherein said exposing step (b) is a vapor phase reaction that involves contacting at least a portion of said CF 3 CHFCH 2 F with at least one metal-based catalyst selected from the group consisting of Ni-mesh, Ni/C, Cr 2 O 3 , activated carbon, Pd/C, and FeCl 3 .
9. The process of claim 8 wherein said metal-based catalyst is at least one of Pd/C or Ni/C.
10. The process of claim 9 wherein said exposing step is at least partially conducted at a temperature of from about 200° C. to about 500° C.
11. A process for the synthesis of 2,3,3,3 tetrafluoropropene comprising:
(a) reacting hydrogen fluoride at a temperature of from about 0° C. to about 250° C. and at a pressure of from about 500 to about 1000 psig with a compound of formula (IIA)
CH 2 X 2 CX 2 ═CX 2 X 2 (IIA)
to produce an intermediate reaction product comprising from about 40 wt. % to about 70 wt. % CF 3 CHFCH 2 F, and
(b) exposing at least a portion of said intermediate reaction product to reaction conditions effective to convert said CF 3 CHFCH 2 F to a compound of formula (IVA)
CF 3 CF═CH 2 (IVA),
wherein each X 2 is each independently selected from the group consisting of chlorine, bromine, fluorine and iodine, wherein said exposing step (b) comprises liquid phase reaction or a vapor phase reaction, wherein the liquid phase reaction comprises contacting at least a portion of CF 3 CHFCH 2 F with a potassium hydroxide solution and wherein the vapor phase reaction comprises contacting at least a portion of CF 3 CHFCH 2 F with a metal-based catalyst selected from the group consisting of Ni-mesh, Ni/C, Cr 2 O 3 , activated carbon, Pd/C, and FeCl 3 .
12. A process for the synthesis of 2,3,3,3-tetrafluoropropene comprising:
(a) reacting hydrogen fluoride (HF) at a temperature of from about 0° C. to about 250° C. and at a pressure of from about 500 to about 1000 psig with a compound of formula (IIA)
CH 2 X 2 CX 2 ═CX 2 X 2 (IIA)
to produce an intermediate reaction product comprising from about 40 wt % to about 70 wt. % CF 3 CHFCH 2 F and further comprising one or more compounds selected from the group consisting of CF 3 CFClCH 3 ; CF 3 CHFCH 2 Cl; and CF 3 CHClCH 2 Cl;
(b) exposing said intermediate reaction product to reaction conditions effective to convert said intermediate reaction product to a compound of formula (IV)
CF 3 CZ═CH 2 (IV)
wherein each X 2 is independently selected from the group consisting of hydrogen, chlorine, bromine, fluorine and iodine, Z is F wherein said exposing step (b) comprises a liquid phase reaction or a vapor phase reaction, wherein the liquid phase reaction comprises contacting the intermediate reaction product with a potassium hydroxide solution and wherein the vapor phase reaction comprises contacting the intermediate reaction product with a metal-based catalyst selected from the group consisting of Ni-mesh, Ni/C, Cr 2 O 3 , activated carbon, Pd/C, and FeCl 3 .