Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1990-10-31
1992-09-22
Evans, Joseph E.
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
20415769, 204 4M, 549532, 568560, C07D30106, C07D30308, C08F 246, C07C17900
Patent
active
051498421
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a process for the preparation of peroxidic perfluoropolyalkylenoxy compounds, more commonly referred to as peroxidic perfluoropolyethers.
In particular, the present invention relates to a process for preparing peroxidic perfluoropolyethers comprising perfluoroalkylenoxy units having at least two carbon atoms. These compounds are prepared, according to the art, by reacting perfluoroolefins with oxygen under irradiation with ultraviolet light.
This technique exhibits the drawback of being delicate and complex, as it requires the use of ultraviolet radiation generators and of reactors of suitable construction in order to permit the radiation to penetrate and to spread inside the reacting phase. Furthermore, since these reactions are usually conducted at very low temperatures, even lower than -50.degree. C., it is necessary to have available efficient means of eliminating the heat associated with the generation of the ultraviolet radiation. Moreover, the reaction yield and the product structure are strongly affected by the amount and distribution of the radiation inside the reaction medium, which considerably limits the desired production flexibility provided by a given reactor.
U.S. Pat. No. 4 460 514 relates to the preparation of non-peroxidic oligomers of (CF.sub.2 O) having a --CF.sub.2 --COF end group. These oligomers are useful for the preparation of s-triazines with perfluoroxymethylene substituent groups. In example IIa, perfluoro-3-methylbutene-1, CF.sub.2 .dbd.CF--CF(CF.sub.3).sub.2, is reacted, in the gas phase, with oxygen in the presence of CF.sub.3 OF without the use of ultraviolet radiation, which affords, at the end of the reaction, the unreacted olefin, (CF.sub.3).sub.2 CF--CFO and a small amount of non-peroxidic oligomers of (CF.sub.2 O) having a CF.sub.2 --COF end group.
It has now, surprisingly, been found that the preparation of peroxidic perfluoropolyethers comprising perfluoroalkylenoxy units having at least two carbon atoms may be effected without the use of ultraviolet radiation if the perfluoroolefins are reacted, in the liquid phase, with oxygen in the presence of particular reagents.
It is, thus, an object of the present invention to provide a process which affords peroxidic perfluoropolyethers comprising perfluoroalkylenoxy units having at least two carbon atoms without using ultraviolet radiation or using UV-irradiation only as complementary measure.
Another object is to provide a process which is simple, can be carried out in apparatus commonly used in the field of chemical processes and can be controlled simply by regulating the amount of reagents introduced in the course of the reaction.
A further object is to provide a very flexible process which permits to obtain, by varying the operative modalities, a wide range of products with different structural characteristics.
Still another object is to provide a process which results in peroxidic perfluoropolyethers having a very low ratio of --COF end groups to non-functional end groups.
These and still further objects are achieved by the process according to the present invention for preparing peroxidic perfluoropolyethers comprising perfluoroalkylenoxy units having at least two carbon atoms.
This process is characterized in that one or more perfluoroolefins (except tetrafluoroethylene used alone) are reacted with oxygen in the liquid phase at a temperature not exceeding 50.degree. C. and in the presence of one or more compounds having one or more F--X bonds, in which X is selected from the group consisting of F, O and Cl.
In particular, when X is oxygen, said compound is an oxygen fluoride or an organic compound containing one or more fluoroxy groups. More usually, it is a perhalogenated alkyl or alkylene compound (the halogen atoms of which being F atoms or F and Cl atoms), containing one or more fluoroxy groups and, optionally, one or more heteroatoms, in particular oxygen atoms.
Said compound usually contains one or two fluoroxy groups. Preferably it is a perfluorinated compound; when it is a per
REFERENCES:
patent: 3392097 (1960-07-01), Gozzo et a.
patent: 3451907 (1969-06-01), Sianesi et al.
patent: 3622601 (1971-11-01), Dale
patent: 3639429 (1972-02-01), Weinmayrz
patent: 3650928 (1972-03-01), Sianesi et al.
patent: 3704214 (1972-11-01), Sianesi et al.
patent: 3715378 (1973-02-01), Sianesi et al.
patent: 3847978 (1974-11-01), Sianesi et al.
patent: 4384128 (1983-05-01), Krespan et al.
Marchionni Giuseppe
Marraccini Antonio
Sianesi Dario
Austimont S.r.l.
Evans Joseph E.
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