Application of Sheppard

• Decision Date: 17 December 1964
• Docket Number: Patent Appeal No. 7259.
• Citation: 52 CCPA 859,339 F.2d 238
• Parties: Application of William A. SHEPPARD.
• Court: U.S. Court of Customs and Patent Appeals (CCPA)

52 CCPA 859, 339 F.2d 238 (1964)

Application of William A. SHEPPARD.

Patent Appeal No. 7259.

United States Court of Customs and Patent Appeals.

December 17, 1964.

Gary A. Samuels, Wilmington, Del. (C. Harold Herr, Wilmington, Del., Frederick Schafer, Washington, D. C., of counsel), for appellant.

Clarence W. Moore, Washington, D. C. (Raymond E. Martin, Washington, D. C., of counsel), for Commissioner of Patents.

Before WORLEY, Chief Judge, and RICH, MARTIN, SMITH, and ALMOND, Judges.

WORLEY, Chief Judge.

This appeal is from the decision of the Board of Appeals which affirmed the examiner's rejection of product claims 2 and 3 in appellant's application¹ for "Arylsulfur Pentafluorides and their Preparation." Two process claims were allowed.

The nature of the subject matter involved is reflected in the appealed claims:

"2. Compounds of the formula

XnR(SF5)m,

wherein R is an aromatic hydrocarbon group, X has a maximum of eighteen carbons and is a member of the group consisting of halogen, hydroxyl, thiol, hydrocarbyl, halohydrocarbyl, oxahydrocarbyl, thiahydrocarbyl, hydrocarbonyl, hydrocarbonyloxy, carboxy and groups hydrolyzable thereto, and sulfo and groups hydrolyzable thereto, m is a whole number of 1-3, inclusive, and n is a cardinal number of from zero to 5, inclusive.

"3. Phenylsulfur pentafluoride."

Appellant states in his specification that "the compounds of the invention are characterized by excellent thermal and chemical stability" and "* * * the sulfur pentafluoride group is resistant to hydrolysis under acidic, basic and neutral conditions." The compounds are said to be useful as fluids for high temperature power transmissions, hydraulic systems or liquid-coupled mechanical drives, and as solvents for highly fluorinated polymer compositions useful in waterproofing cellulose materials.

The reference relied on is: Emeleus et al., J. Chem.Soc. (London), Vol. of 1946, pp. 1126-1131.

That article relates to preparation of alkyl- and aryl- substituted fluorides of sulfur, selenium and tellurium, with the following portions particularly pertinent:

"The fluorides of sulfur, selenium, and tellurium show decided differences from the other halides of these elements. For instance, in all three cases the maximum covalency of 6 is reached in combination with fluorine, but not with the other halogens, even at low temperatures. The hexafluorides are exceptionally stable, whereas the other halides, including the fluorides, easily hydrolyse and dissociate when heated. Indeed, some doubt exists as to the formation of lower fluorides of selenium and tellurium. Considerable interest, therefore, attaches to the preparation and properties of the alkyl- and aryl- substituted fluorides of these elements. Experiments are described below which seem to show that substituted hexafluorides such as RSF5 are not stable * * *.

* * * * * *

"Experimental.

* * * * * *

"Fluorination of the Substituted Dihalides. — No fluorine derivatives in this series were isolated. Attempts were made to replace chlorine by fluorine in PhSCl, o-NO2.C6H4.SCl, o-NO2.C6H4. SBr, and p-NO2.C6H4.SCl, with silver, mercurous, mercuric, and hydrogen fluoride. All these substances reacted with the metallic fluorides, but the product always consisted mostly of the corresponding disulphide, mixed with tarry matter containing some fluorine * * *.

* * * * * *

"Higher-substituted Fluorides. — No analogues of the compounds SRF3, SRF5 and SeRF5 exist for the other halogens. It was therefore necessary to choose methods of preparation other than by way of the usual metal fluorides or hydrogen fluoride. Experiments were made on the following lines: (1) The action of Grignard reagents upon sulphur tetra- and hexa-fluoride. (2) The action of fluorine, or phenyliodonium fluoride, upon the organic disulphides and diselenides.

"(1) Gaseous sulphur hexafluoride bubbled through an ethereal solution of phenylmagnesium bromide did not react below the b.p. of ether. Liquid `sulphur tetrafluoride\' * * * reacted violently with phenylmagnesium bromide in ether at -60°. The products, however, contained no volatile fluorine compound and apparently consisted of PhSBr and bromine * * *.

"(2) The reaction at 0° between fluorine-nitrogen mixtures and chloroform solutions of diphenyl diselenide or o- or p-nitro-phenyl disulphide yielded only hydrogen fluoride and tarry or high-boiling condensation products. * * *

* * * * * *

"Discussion

"From the work described, the following conclusions emerge: (1) The substituted fluorides of sulphur, selenium, and tellurium are much less stable than the other halides. Stability increases from fluorine to iodine. (2) Stability increases in all the halides with the number of organic radicals in the molecule, and most noticeably in the fluorides. (3) Stability increases from sulphur to tellurium.

* * * * * *

"* * * The results of the attempts to fluorinate the phenyl sulphur halides can be explained as follows: The phenyl sulphur fluoride first formed disproportionated to a mixture of the disulphide and a higher fluoride e. g., p-NO2.C6H4.SF to (p-NO2.C6H4.S)2 and p-NO2.C6H4. SF3 or p-NO2.C6H4.SF5; the latter then decomposed by intermolecular condensations to hydrogen fluoride and tarry products. * * *"

The examiner rejected claims 2 and 3 over Emeleus, stating that the claimed compounds differ from the reference compound, p-NO2.C6H4.SF5, in that they contain either no substituent on the phenyl group (as in phenylsulfur pentafluoride), or some substitutent other than a nitro group (as in the Markush grouping set forth in claim 2). He regarded the claimed compounds as "unpatentable analogs" of the nitro compound of Emeleus, since the "nitro group is as close to some of the members of the Markush group as they are to each other." Presumably the statutory basis for the examiner's rejection is 35 U.S.C. § 103.

After observing that halogen is a member of the Markush group set forth by appellant, the board affirmed the examiner's rejection of claim 2² on Emeleus. It noted "the analogy between a nitro group and a chloro group as a substituent has long been recognized," citing In re Taub, 125 F.2d 719, 29 CCPA 893. In response to appellant's argument that his compounds are stable, whereas the reference compounds are described as being unstable, the board stated:

"* * * In view of the great variety of compounds that are described by appellant as being very stable it seems highly unlikely that only the nitro variant would be unstable even if it were pure. If in fact there is a difference in stability it can with reason only be attributed to differences in the mode of preparation resulting either in differing kinds and/or degrees of impurity * * *."

On the basis of its own study of Emeleus, the board also regarded the reference to anticipate claim 3, hence claim 2, under 35 U.S.C. § 102(a), reasoning:

"* * * the p-nitro phenylsulfur pentafluoride compound mentioned * * * is merely exemplary of results obtained by the experiments described * * * in the paragraph entitled, `Fluorination of the Substituted Dihalides.\' * * * That paragraph does not mention any sulfur pentafluorides but states that attempted fluorination of phenylsulfur chloride and p-nitrophenyl sulfur chloride with metallic fluorides yielded corresponding disulfides and a tarry matter and hydrogen fluoride. * * * The "Discussion" portion of Emeleus has a more detailed explanation in some respects and states that it is a `higher fluoride\' which decomposes to yield the hydrogen fluoride and tarry products and that this higher fluoride could be a phenyl sulfur pentafluoride. Appellant has not denied that such a pentafluoride is obtained, and, this being the case, we must assume that the experiments yielded phenyl sulfur pentafluoride as well as the p-nitro compound. The reference clearly teaches one skilled in the art the possible existence of phenyl sulfur pentafluoride just as well as it teaches that of the nitro compound.

* * * * * *

"* * * We have made it clear that the compound of claim 3 is explicitly taught by Emeleus et al. and we, accordingly, hold that claims 2 and 3 are unpatentable over the reference for this reason also. Their allowance would be contrary to 35 U.S.C. § 102(a) * * *."

With that background information, we must determine the correctness of the rejections of claims 2 and 3 under 102(a) and claim 2 under 103. From our evaluation of the record we are inclined to conclude that the board erred in both instances.

REJECTION UNDER 35 U.S.C. § 102(a)

We begin by agreeing with the board that Emeleus "teaches one skilled in the art the possible existence of...