Appeal No. 1997-1959
Application 08/351,908
dichlorohexafluoropropane with hydrogen in the presence of palladium supported on fluorinated
alumina, aluminum fluoride and mixtures thereof at the stated temperature encompassed by appealed
claims 1 and 8 would have been obvious over the combined teachings of Kellner I and Smith to one of
ordinary skill in this art at the time the claimed invention was made.
As pointed out by the examiner in the answer, one of ordinary skill in this art would have found
in the combined teachings of Kellner I and Smith the reasonable expectation of hydrodechlorinating a
fluorochlorocarbon structurally similar to the fluorochlorocarbons of the references with hydrogen in the
presence of a supported palladium hydrodechlorination catalyst. with the reasonable expectation that at
least one if not all of the chloro substituents would be preferentially replaced by hydrogen. In re Dow
Chemical Co., 837 F.2d 469, 473, 5 USPQ2d 1529, 1531 (Fed. Cir. 1988) (“Both the suggestion
and the expectation of success must be founded in the prior art, not in applicant’s disclosure.”). We
find that Kellner I discloses the hydrodechlorination of 1,1,1,2-tetrafluorochloroethane (CF3CHClF)
with hydrogen in the presence of a catalyst consisting essentially of palladium supported on aluminum
fluoride or fluorinated alumina to obtain 1,1,1,2-tetrafluoroethane (CF3CH2F) (e.g., col. 2). We find
that Smith discloses the hydrodechlorination of 1,2,2-trichloropentafluoropropane (CF3CCl2CClF2)
with hydrogen in the presence of a catalyst consisting of palladium supported on activated carbon to
obtain, depending on the amount of hydrogen used, 1,1,1,3,3-pentafluoropropane (CF3CH2CHF2),
1,1,1,3,3-pentafluoropropene (CF3CH=CF2), or 1,1,1,3,3-pentafluoro-2-chloro-propene
(CF3CCl=CF2) (e.g., cols. 1 and 2). Indeed, as pointed out by the examiner, one of ordinary skill in
this art would have recognized from these teachings that a supported palladium hydrogenation catalyst
will hydrodechlorinate a secondary dichloro substituted carbon as well as a terminal fluorochlorocarbon.
Thus, we agree with the examiner’s conclusion that, prima facie, one of ordinary skill in this art
would have found in the combined teachings of Kellner I and Smith the reasonable suggestion to
hydrodechlorinate the analogous, known compound 2,2-dichlorohexafluoropropane (CF3CCl2CF3),
which contains a secondary chloro substituted carbon, with hydrogen in the presence of a supported
palladium catalyst, such as palladium supported on aluminum fluoride or fluorinated alumina as taught by
Kellner I, in the reasonable expectation of obtaining the analogous, known products 2,2-dihydro-
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