Method for preparing partially fluorinated alcohol
11897832 ยท 2024-02-13
Assignee
Inventors
Cpc classification
C07D303/08
CHEMISTRY; METALLURGY
C07C29/64
CHEMISTRY; METALLURGY
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
C07C29/64
CHEMISTRY; METALLURGY
Abstract
A method for preparing a partially fluorinated alcohol, comprises reacting an epoxide: wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from the group comprising H, F, Cl, Br, I, CF.sub.3, alkyl, fluoroalkyl, haloalkyl with a fluorinating agent.
Claims
1. A method for preparing a partially fluorinated alcohol, comprising: reacting an epoxide: ##STR00024## with a fluorinating agent; wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from the group consisting of H, F, Cl, Br, I, CF.sub.3, alkyl, fluoroalkyl, and haloalkyl; where at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is CF.sub.3, and at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is H.
2. The method according to claim 1, where the fluorinating agent comprises a nucleophilic fluorinating agent.
3. The method according to claim 1, where the fluorinating agent is selected from HF and complexes of HF with nitrogen containing species.
4. The method according to claim 3, where the complexes of HF with nitrogen containing species are selected from the group comprise Olah's reagent (HF:Pyridine complex), HF with urea, HF with a tertiary amine, or combinations thereof.
5. The method according to claim 1, where one of R.sup.1 to R.sup.4 is CF.sub.3, one of R.sup.1 to R.sup.4 is F and two of R.sup.1 to R.sup.4 are H.
6. The method according to claim 1, where two of R.sup.1 to R.sup.4 are CF.sub.3 and two of R.sup.1 to R.sup.4 are H.
7. The method according to claim 1, where one of R.sup.1 to R.sup.4 is CF.sub.3 and three of R.sup.1 to R.sup.4 are H.
8. The method according to claim 1, where one of R.sup.1 to R.sup.4 is CF.sub.3, one of R.sup.1 to R.sup.4 is Cl and two of R.sup.1 to R.sup.4 are H.
9. The method according to claim 4, where the complexes of HF with nitrogen containing species comprises Olah's reagent and the ratio of HF to pyridine is 7:3 by weight.
10. The method according to claim 5, where R.sup.1 is F and R.sup.3 is CF.sub.3, R.sup.2 and R.sup.4 are H; or R.sup.1 is F and R.sup.2 is CF.sub.3, and R.sup.3 and R.sup.4 are H.
11. The method according to claim 5, where or R.sup.1 is F and R.sup.2 is CF.sub.3, and R.sup.3 and R.sup.4 are H.
12. The method according to claim 6, where R.sup.1 is CF.sub.3 and R.sup.3 is CF.sub.3; R.sup.2 is H and R.sup.4 is H.
13. The method according to claim 7, where R.sup.1 is CF.sub.3, R.sup.2, and R.sup.3 and R.sup.4 are H.
14. The method according to claim 8, where R.sup.1 is Cl, R.sup.3 is CF.sub.3, and R.sup.2 and R.sup.4 are H.
15. The method according to claim 8, where R.sup.1 is Cl, R.sup.2 is CF.sub.3, and R.sup.3 and R.sup.4 are H.
16. The method according to claim 1, with the provision that the partially fluorinated alcohol is not 1,1,1,3-tetrafluoropropan-2-ol.
17. The method according to claim 7, with the provision that the partially fluorinated alcohol is not 1,1,1,3-tetrafluoropropan-2-ol.
18. The method according to claim 1, further comprising preparing the epoxide by reacting a partially fluorinated alkene: ##STR00025## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from the group consisting of H, F, Cl, Br, I, CF.sub.3, alkyl, fluoroalkyl, and haloalkyl, where at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is CF.sub.3 and at least of one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is H; with an oxidising agent to form a partially fluorinated epoxide.
19. The method according to claim 18, wherein the oxidising agent is selected from the group consisting of air, oxygen and oxygen containing compounds, where the oxygen containing compounds optionally comprise peroxides, per-salts or compounds of oxygen with other elements.
20. The method according to claim 18, wherein the oxidising agent comprises a hypohalite.
21. The method according to claim 18, wherein the alkene comprises a tetrafluoropropene or a pentafluoropropene.
22. The method according to claim 21, wherein the alkene comprises 1,3,3,3-tetrafluoropropene (1234ze) or 2,3,3,3-tetrafluoropropene (1234yf).
23. The method according to claim 21, wherein the alkene comprises 1,1,3,3,3-pentafluoropropene (1225zc).
24. The method according to claim 1, wherein the epoxide is a partially fluorinated epoxide, and the method further comprises reacting the partially fluorinated epoxide with a first fluorinating agent to form a compound having at least either of the following structures: ##STR00026## wherein at least two of R.sup.1 to R.sup.4 independently are H, Cl, Br, or I; and reacting the compound having the at least either of the above structures with a second fluorinating agent.
25. The method according to claim 20, wherein the oxidising agent comprises chlorite.
Description
EXAMPLES
Example 1Ring Opening of an Epoxide with Olah's Reagent
(1) The following steps were followed. The reactor was charged with Olah's reagent (70% HF:Pyridine, 5 ml) and cooled in an ice batch with stirring. 2,3-epoxy1,1,1-trifluoropropane (TFPO) (3.4 g) was then added dropwise. At the end of the addition the reaction mixture was allowed to warm up to room temperature; stirring was continued for 48 hours. After 48 hours the reaction mixture was quenched with ice. Salt was added, and the product extracted with diethyl ether (35 ml). The diethyl ether extracts were combined, washed with saturated potassium bicarbonate solution and water before being dried over anhydrous sodium sulphate. Diethyl ether was removed in vacuo to yield the desired product as a clear, colourless liquid boiling point 91-93 C. The identity of this product was confirmed by NMR spectroscopy.
Example 2Ring Opening of 2,3-epoxy-1,1,1,3-tetrafluoropropane with Olah's Reagent
(2) ##STR00021##
(3) 2,3-epoxy-1,1,1,3-tetrafluoropropane was ring opened using the following procedure: A 100 ml Hastalloy C pressure reactor was charged with Olah's reagent (70% HF:Pyridine, 25 g). After sealing, the contents of the reactor were cooled to 20 C. with stirring. 2,3-epoxy-1,1,1,3-tetrafluoropropane (11 g) was then added. After this addition was complete the reaction mixture was heated to 50 C. and stirred for 168 hours. After 168 hours the reaction mixture was quenched with ice and saturated sodium chloride solution (22 ml) added. The product was extracted from this mixture with diethyl ether. The diethyl ether extracts were combined, washed with saturated potassium bicarbonate solution and then water before being dried over anhydrous sodium sulphate. The identity of the product was confirmed by NMR spectroscopy.
Example 2aRing Opening of 2,3-epoxy-1,1,1,3-tetrafluoropropane with Olah's Reagent
(4) ##STR00022##
(5) 2,3-epoxy-1,1,1,3-tetrafluoropropane was ring opened using the following procedure: A 100 ml Hastalloy C pressure reactor was charged with Olah's reagent (70% HF:Pyridine, 25 g). After sealing, the contents of the reactor were cooled to 20 C. with stirring. 2,3-epoxy-1,1,1,3-tetrafluoropropane (10.6 g) was then added. After this addition was complete the reaction mixture was heated to 80 C. and stirred for 43 hours. After 43 hours a sample of the reaction mixture was analysed by GCMS and it was found that all the feed epoxide had reacted. After cooling the reaction mixture was quenched with ice and saturated sodium chloride solution (22 ml) added. The product was extracted from this mixture with diethyl ether. The diethyl ether extracts were combined, washed with saturated potassium bicarbonate solution and then water before being dried over anhydrous sodium sulphate. The identity of the product was confirmed by NMR spectroscopy.
Example 3Ring Opening of 2,3-epoxy-1,1,1-trifluoro-2-(trifluoromethyl)propane with Olah's Reagent
(6) ##STR00023##
(7) 2,3-epoxy-1,1,1-trifluoro-2-(trifluoromethyl)propane was ring opened using the following procedure: A 100 ml Hastalloy C pressure reactor was charged with Olah's reagent (70% HF:Pyridine, 16.5 g). After sealing, the contents of the reactor were cooled to 20 C. with stirring. 2,3-epoxy-1,1,1-trifluoro-2-(trifluoromethyl)propane (10 g) was then added. After this addition was complete the reaction mixture was heated to 50 C. and stirred for 160 hours. After 160 hours the reaction mixture was quenched with ice and saturated sodium chloride solution (22 ml) added. The product was extracted from this mixture with diethyl ether. The diethyl ether extracts were combined, washed with saturated potassium bicarbonate solution and then water before being dried over anhydrous sodium sulphate. The identity of the product was confirmed by NMR spectroscopy.
Example 4Preparation of di-(1,1,1,3-tetrafluoropropyl) carbonate with Phosgene
(8) Di-(1,1,1,3-tetrafluoropropyl) carbonate was synthesised using the following procedure: A three necked round bottom flask was cooled to 0 C. under an inert atmosphere. Phosgene solution (15% by weight in toluene, 50 mL of solution) was added and stirred. A mixture of 1,1,1,3-tetrafluoropropan-2-ol (18.42 g) and pyridine (11.02 g) was added to the solution dropwise, and the temperature of the solution was monitored to ensure it did not rise above 10 C. The solution was allowed to warm to room temperature and stirred for 48 hours. The product was filtered to remove pyridinium salts and the solvent was removed in vacuo to yield the crude product. The crude product was distilled under atmospheric conditions to yield di-(1,1,1,3-tetrafluoropropyl) carbonate as a yellow oil (7.08 g, 35% yield).
FIGURES
(9) The Figures illustrates the results of various spectroscopic analytical techniques carried out on some of the reaction products from the Examples.
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