Staged synthesis of diiodoperfluoro-C3 to C7-alkanes

Patent metadata

Field	Value
Publication number	US-9637430-B2
Application number	US-201615053699-A
Country	US
Kind code	B2
Filing date	Feb 25, 2016
Priority date	Feb 27, 2015
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

The process is provided for forming the reaction product comprising the homologue mixture of I(CF 2 ) n I, wherein n is 3 to 7, which may contain at least one of the contaminants ICF 2 I and I(CF 2 ) 2 I, by the steps comprising (a) reacting iodine with hexafluoropropylene oxide at a temperature of 150° C. to 210° C. in a reactor, the amount of said hexafluoro-propylene oxide being a portion of the total amount of hexafluoropropylene oxide to be reacted with said iodine, thereby forming a reaction product containing gaseous perfluoroacetyl fluoride as a reaction by-product, (b) cooling said reaction product to become liquid except for said gaseous perfluoroacetyl fluoride, (c) venting said perfluoroacetyl fluoride from said reactor, and (d) repeating said steps (a), (b), and (c) until said total amount of said HFPO is reacted with said iodine.

First claim

What is claimed is:

1. A process of forming the reaction product comprising the homologue mixture of I(CF 2 ) n I, wherein n is 3 to 7, which contains at least one of the contaminants ICF 2 I and I(CF 2 ) 2 I, by the steps comprising
(a) reacting iodine with hexafluoropropylene oxide at a temperature of 150° C. to 210° C. in a reactor, the amount of said hexafluoropropylene oxide being a portion of the total amount of hexafluoropropylene oxide to be reacted with said iodine, thereby forming a reaction product containing gaseous perfluoroacetyl fluoride as a reaction by-product,
(b) cooling said reaction product to become liquid except for said gaseous perfluoroacetyl fluoride,
(c) venting said perfluoroacetyl fluoride from said reactor, and
(d) repeating said steps (a), (b), and (c) until said total amount of said HFPO is reacted with said iodine,
and obtaining as a result thereof said reaction product comprising said homologue mixture.

2. A process of forming the reaction product comprising the homologue mixture of I(CF 2 ) n I, wherein n is 3 to 7, which contains at least one of the contaminants ICF 2 I and I(CF 2 ) 2 I, by the steps comprising
(a) reacting iodine with hexafluoropropylene oxide at a temperature of 150° C. to 210° C. in a reactor, the amount of said hexafluoropropylene oxide being a portion of the total amount of hexafluoropropylene oxide to be reacted with said iodine, thereby forming a reaction product containing gaseous perfluoroacetyl fluoride as a reaction by-product,
(b) cooling said reaction product to become liquid except for said gaseous perfluoroacetyl fluoride,
(c) venting said perfluoroacetyl fluoride from said reactor, and
(d) repeating said steps (a), (b), and (c) until said total amount of said HFPO is reacted with said iodine,
and obtaining as a result thereof said reaction product comprising said homologue mixture,
wherein the portion of said hexafluoropropylene oxide reacted in each of said step (a) is from 10 to 50% of said total amount of said hexafluoropropylene oxide reacted with said iodine.

3. The process of claim 1 wherein the molar proportion of said total amount of said hexafluoropropylene oxide reacted with said iodine is at least 3.0.

4. The process of claim 1 wherein the yield of said reaction product after step (d) is at least 70%.

5. The process of claim 1 wherein said homologue mixture of I(CF 2 ) n I, wherein n is 3 to 7 resulting in the carrying out of said process comprises at least 90% (GC area) of said reaction product.

6. The process of claim 1 wherein said contaminants ICF 2 I and I(CF 2 ) 2 I, are present in said reaction product in amounts of no greater than 1% and no greater than 0.1%, respectively.

7. The process of claim 1 further comprising heating said reaction product to at least 220° C. at least after the last step (a) of said repeating said steps (a), (b) and (c).

8. The process of claim 1 wherein said reacting in step (a) is carried out in the presence of catalyst.

9. The process of claim 8 wherein said reacting step is carried out in the absence of added catalyst.

Assignees

• Chemours Co Fc Llc

Inventors

• Hung Ming Hong
• Marchione Alexander Anthony
• Morken Peter A

Classifications

• C07C17/272 Primary

  by addition reactions · CPC title

• C07C17/204

  the other compound being a halogen · CPC title

• C07C19/16

  and iodine · CPC title

• C07C17/093 Primary

  by replacement by halogens · CPC title

• C07C17/26

  by reactions involving an increase in the number of carbon atoms in the skeleton · CPC title