DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Applicant’s election of Group (III) in the reply filed on 07/24/2026 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claims 1-2, 19-20, and 22-25 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.
Priority
This application is the U.S. National Stage of International Patent Application No. PCT/IN2022/050495, filed May 27, 2022, which claims the benefit of Indian Application No. 202121023677, filed May 27, 2021.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 02/20/2024, 10/13/2024, 02/26/2025, & 07/24/2026 has been considered by the examiner.
Drawings
The drawings are objected to because Figure 1/1 is of insufficient clarity and legibility. The numerical annotations identifying the diffraction peaks, as well as portions of the axis markings and associated indicia, are too small, faint, and/or crowded to be readily legible. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Status
Claims 1-25 are pending. Claims 1-2, 19-20, and 22-25 are withdrawn. Claims 3-18 and 21 are examined in accordance to the elected species.
Claim Objections
Claims 3-18 are objected to because of the following informalities:
In claims 3 and 4, the recitation “A process for preparation of Pyroxasulfone” should preferably read “A process for preparing of Pyroxasulfone” or “A process for the preparation of Pyroxasulfone.”
In claims 5, 7-9, 12, 15, and 17. The phrase “in presence of” should preferably read “in the presence of.”
In claim 6, the phrase “selected from group comprising of” is grammatically improper. However, because the use of open-ended terminology “comprising” in defining the group also creates uncertainty concerning the scope of the alternatives encompassed by the claim, this matter is additionally addressed below under 35 U.S.C. 112(b).
In claim 10, the phrase “selected from group consisting of” is grammatically improper, and “or mixture thereof.” The indefiniteness resulting from the open-ended grouping is separately addressed below.
In claim 13, “an organic peroxides compound” is grammatically improper and should preferably read “an organic peroxide compound” if that is Applicant’s intended meaning. The substantive uncertainty concerning the scope of this limitation is separately addressed under 35 U.S.C. 112(b).
In claim 16, “selected from group comprising of” is grammatically improper, and “mixture thereof.” The indefiniteness of the open grouping is addressed separately below.
In claim 18, the recitation “further comprises a process for purification of pyroxasulfone comprising treating pyroxasulfone…” is grammatically awkward because the claimed subject matter is itself a process. Applicant is advised to consider reciting, for example, that the process “further comprises purifying the Pyroxasulfone by treating the Pyroxasulfone… “ The present wording, however, is understood sufficiently for examination and is not, on this record, separately rejected under 35 U.S.C. 112(b).
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 3 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 3 recites a process for preparation of “Pyroxasulfone of formula (VII).” However, formula (VII) is neither depicted nor otherwise structurally defined in claim 3, and claim 3 is an independent claim and therefore does not incorporate a definition of formula (VII) from another claim. Consequently, the structural subject matter intended by the recitation “Pyroxasulfone of formula (VII)” cannot be determined from the claim itself with reasonable certainty.
In contrast, independent claim 4 expressly depicts the compound identified as formula (VII). Accordingly, the deficiency in claim 3 is not merely the absence of a reference numeral or other typographical informality; claim 3 invokes a formula designation without defining the formula to which the designation refers.
Claim 3 is also rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being incomplete for omitting essential steps, such omission amounting to a gap between the steps. See MPEP § 2172.01. The omitted steps are “converting steps by which compound of formula (I) or its salt to pyrosaxulfone of formula (VII).” This recitation merely identifies the starting material and desired final product without positively reciting the acts by which the compound of formula (I) is converted to pyroxasulfone. The omitting step is material to the claimed process. As evidenced by the process expressly recited in claim 4, conversion from formula (I) to pyroxasulfone involves intervening operation including reaction of formula (I) with the isooxazoline compound of formula (III) to obtain formula (IV), conversion of formula (V) to formula, fluoromethylation to obtain formula (VI), and oxidation of formula (VI) to obtain pyroxaxulfone of formula (VII).
Applicant’s specification likewise demonstrates that these are substantive chemical consequences transformation rather than an inherent consequence of merely possessing compound (I). For example, Applicant’s Example 7 expressly performs fluoromethylation leading to the formula (VI) intermediates, whereas Examples 8-10 subsequently perform oxidation of the corresponding thioether to obtain pyroxasulfone.
Accordingly, the generic instruction to “convert” compound (I) to pyroxasulfone leaves a gap in the positively recited process steps and fails to distinctly define what acts constitute the claimed conversion.
Claim 21 likewise fails to positively recite the steps necessary to define the purported method. Claim 21 recites “[a] method of using compound of formula (I) or its salt, in the process for preparation of pyroxasulfone of formula (VII),” but fails to specify how the compound of formula (I) is used, what act is performed upon or with the compound, or what positively recited step constitutes the claimed method.
The mere statement that compound of formula (I) is used “in the process for preparation of pyroxasulfone” identifies an intended use or objective but does not define the acts required to carry out the purported method. Consequently, it cannot be determined with reasonably certainty what conduct falls within the scope of the claimed method.
Claims 6, 10, 16, and 17 recite the open-ended selection groups. Each claim purports to define a particular member by selection from a group while defining that group using the open-ended transitional terminology “comprising.” Specifically, claim 6 recites an organic solvent “selected from [a] group comprising of” lower alcohols, hydrocarbons, halogenated hydrocarbons, ketones and ethers; claim 10 similarly defines the polar solvent’ claim 16 defines the metal catalyst; and claim 17 defines the solvent used during oxidation.
The use of “comprising” render the recited group open to additional, unidentified members. At the same time, the language “selected from the [the] group” purports to define the claimed member by reference to the members of that group. It is therefore unclear what additional unrecited alternatives, if any, satisfy the claimed selection.
Accordingly, the boundaries of the claimed solvent, or catalyst cannot be determined with reasonably certainty. Applicant may wish to clarify the scope, by employing a closed grouping such as “selected from the group consisting of …”
Claim 13 recites “said oxidizing agent is an organic compound selected from m-chloroperbenzoic acid, performic acid, peracetic acid; inorganic peroxides such as hydrogen peroxide, potassium permanganate, sodium periodate or potassium peroxymonosulfate.”
The scope of the “oxidizing-agent” limitation is unclear for several related reasons.
First, the claim initially characterizes “said oxidizing agent” as “an organic acid peroxides compound,” but thereafter recites “inorganic peroxides,” It is therefore unclear whether the oxidizing agent is required to be an organic peroxide, may alternatively be an inorganic peroxide, or encompass a broader class of oxidizing agents.
Second, the expression “such as” introduces the subsequently identified compounds in an exemplary manner. It is therefore unclear whether hydrogen peroxide, potassium permanganate, sodium periodate or potassium peroxymonosulfate constitute the complete set of permitted alternatives or merely examples of a broader, undefined class.
Third, the scope of the asserted class “inorganic peroxides” itself renders uncertain by the subsequently enumerated species. The claim groups hydrogen peroxide, potassium permanganate, sodium periodate or potassium peroxymonosulfate under the exemplary language following “inorganic peroxides,” notwithstanding that the listed materials do not all fall within a single clearly defined peroxide class. Thus, one of ordinary skill in the art is left uncertain as to the chemical class or universe of compounds encompassed by the oxidizing-agent limitation.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
the claimed invention is directed to non-statutory subject matter. The claim(s) does/do not fall within at least one of the four categories of patent eligible subject matter, namely a process, machine, manufacture, or composition of matter.
Claim 21 recites “a method of using compound of formula (I) or its salt, in the presence for preparation of pyroxasulfone of formula (VII).” Although the claim is nominally introduced as a “method,” the claim does not positively recite any act of step constituting a process. Rather, the claim merely recites the use of compound (I), or its salt “in” a process for preparing pyroxasulfone without defining what is done with compound formula (I). A claim to a use, without setting forth active steps constituting a process, does not define a process within the meaning of 35 U.S.C. 101. Accordingly, claim 21 fails to fall within one of the statutory categories.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 3-10 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Schaper et al. (US2007/0015805 A1) in view of Uchida (US2007/0185324 A1, cited herein as “Uchida-2007”) and Uchida (US2023/0012374 A1, cited as “Uchida-2023”).
Schaper is directed to process for preparing 3-arylmethylthio- and 3-heteroarylmethylthio-4,5-dihydroisoxazoline derivatives
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. Schaper explains that the corresponding thioether is conventionally prepared and thereafter converted to oxidized derivatives. (See ¶¶ [0002]-[0008], pp. 1-2.) Of particular relevance, Schaper teaches preparing an isothiuronium salt by reacting an alkylating agent of formula R5R6CHLg with thiourea (¶ [0022], pp. 2-3), and subsequently reacting the resulting isothiuronium salt with an isooxazoline derivative under basic condition to obtain the corresponding thioether
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(¶¶ [0017]-[0025], pp. 2-3).
Schaper further explains that the mercaptan generated from the isothiuronium salt is formed in situ and immediately scavenged by the isooxazoline reactant, thereby avoiding isolation and handling of the mercaptan intermediate. (See ¶ [0025], P. 3.) Most significantly, Synthesis Example C, ¶ [0054], p. 4, employes the closely corresponding pyrazole/isooxazoline system. Schaper reacts a 2-(difluoromethoxy)1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)methyl isothiuronium material with 3-chloro-5,5-dimethyl-4,5-dihydroisoxazole in aqueous sodium hydroxide/toluene and obtains the corresponding pyrazole-containing isooxazoline thioether, particularly Compound 35 is identified as the corresponding species having the 5-difluroromethoxy-1-methyl-3-trifluoromethylpyrazol-4yl substituent. (See Table A, ¶¶ [0056]-[0058], p. 5).
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Schaper further expressly states that the compound obtained may, if required, be oxidized and/or halogenated by reactions known to those skilled in the art. (See ¶ [0047], p. 4).
Schaper therefore establishes the claimed pyrazole/isooxazoline thioether framework, the use of an isothiuronium/thiourea-derived sulfur intermediate, and subsequent oxidation of the resulting thioether were known.
Schaper does not teach expressly teach the claimed process in its entirety, particularly the preparation of the compound of Formula (I) from the particular formula (II) precursor and thirourea, or the subsequent claimed sequence for converting Formula (I) through the recited intermediates to pyroxasulfone of Formula (VII), Both Uchida-2007 relied upon to address the former deficiency and to further establish the pertinent thiourea/isothiuronium and 5-hydroxy-1-methyl-3-trifluoroemthyl pyrazole chemistry, while Uchida-2023 is relied upon for the downstream conversion/oxidation chemistry leading to pyroxasulfone.
Uchida-2007 is directed to the preparation of 5-hydroxy4-thiomethylpyrazole compounds useful as intermediates in agricultural chemistry (¶¶ [0001]-[0003], p. 1). Uchida-2007 teaches reacting 5-hydroxypyrazole with a sulfur compound in the presence of base and formaldehyde to produce corresponding 5-hydroxy-4-thiomethylpyrazole (¶¶ [0010]-[0014], pp. 1-2). The reference expressly identifies trifluoromethyl as preferred electron-withdrawing substituent and specifically identifies 5-hydroxy-1-methyl-3-trifluoromethylpyrazole. (See (¶¶ [0095]-[0107], pp. 4-5).
Uchida-2007 further explains that, where the sulfur compound is a thiol, an isothiuronium salt prepared by reaction of the corresponding alkyl halide with thiourea may be hydrolyzed in the reaction vessel to form the reactive thiol in situ. (See ¶¶ [0148]-[0151], p. 7). More particularly, Reference Example 9, ¶ [0191], p. 10, prepares 5,5-dimethyl(4,5-dihydroisoxazol-3-yl)thiocarboxamidine hydrochloride by reacting 3-chloro-5,5-dimethyl-4,5-dihydroisoxazole with thiourea in ethanol/HCl. Thereafter, Example 3, ¶¶ [0200]-[0202], p. 10, reacts 5-hydroxy-1-methyl-3-trifluoromethylpyrazole with that isooxazoline thiocarboxamidine material under basic conditions to obtain the corresponding pyrazole/isooxazoline thioether.
Thus, Uchida-2007 provides an express reason for using the thiourea-derived isothiuronium/isooxazoline sulfur chemistry in precisely the 5-hydroxy-1-methyl-3-trifluoromethylpyrazole environment relevant to the presently claimed chemistry.
Uchida-2023 concerns industrial preparation of the same pyrazole/isooxazoline class and expressly recognizes the resulting sulfide as an intermediate in preparing pyroxasulfone. Its disclosure describes preparation of the pyrazole/isooxazoline sulfide and subsequent oxidation to the corresponding sulfone/pyroxasulfone. The reference’s process includes oxidation of the sulfide using hydrogen peroxide in the presence of a metal catalyst, including tungsten catalyst, thereby furnishing the corresponding sulfone. (See e.g., the process schemes and oxidation disclosure at pp. 1-2 and the detailed oxidation discussion at pp. 41-46.
Schaper does not expressly disclose Applicant’s entire claimed sequence beginning with the particular Formula (II) precursor and proceeding through every intermediate to pyroxasulfone. However, Schaper expressly teaches the relevant thiourea/isothiuronium chemistry, Example C provides the highly pertinent difluoromethoxy/trifluoromethyl pyrazole-isoxazoline thioester, and Schaper expressly teaches subsequent oxidation of its thioester products. Uchida-2007 independently the same type of isooxazoline thiocarboxamidine can be prepared from the corresponding chloroisoxazoline and thiourea, and then coupled in the 5-hydroxy-1-methyl-3-trifluoromethylpyrazole system. It would therefore have been obvious to one of ordinary skill in the art at the time the invention was filed to employ Uchida’s thiourea/isothiuronium methology in Schaper’s closely related pyrazole/isooxazoline synthesis. Both references address preparation of the same class sulfur-linked pyrazole/isooxazoline agricultural intermediates, and both teach the isothiuronium/thiol route as an effective means for constructing the required C-S linkage.
The skilled artisan would have further had reason to subject the resulting sulfide to the oxidation taught by Uchida-2023 because Schaper itself expressly directs the artisan to subsequent oxidation of the thioether, while Uchida-2023 teaches an oxidation specifically applicable to corresponding pyrazole/isooxazoline sulfide for production of the sulfone.
A reasonable expectation of success would have existed because Schaper demonstrates the sulfur-coupling chemistry on the difluoromethoxy/trifluoromethyl pyrazole-isoxazoline scaffold itself; Uchida-2007 experimentally demonstrates preparation and use of the corresponding isooxazoline thiocarboxamidine and its coupling to the 5-hydroxy-1-methyl-3-trifluoromethyl pyrazole scaffold; and Uchida-2023 demonstrates downstream oxidation of the corresponding sulfide chemistry. Thus, the proposed combination employes known transformations on closely corresponding substrates for their known purposes.
With respect to claim 5, Schaper teaches preparation of the isothiuroniium salts from the corresponding alkylating agent and thiourea in inert organic solvents including lower alcohols, hydrocarbons, halogenated hydrocarbons, and eithers, at temperature of 0-150oC, preferably 20-100oC. (See ¶ [0040], p. 4). The use of an organic solvent during the corresponding thiourea reaction therefore would have been obvious.
With respect to claim 6, Schaper expressly identifies methanol, ethanol, and isopropanol, as lower alcohols; benzene and toluene as hydrocarbons; dichloromethane and chloroform as halogenated hydrocarbons; and ether derivatives including methyl tert-butyl ether, tetrahydrofuran and dioxane. (See ¶ [0040], p. 4). Thus, the claimed solvent classes substantially correspond to solvents expressly taught for the thiourea/isothiuronium chemistry.
With respect to claim 7, the acid limitation is consistent with Uchida’s preparation of the isoxazolline thiocarboxamidine hydrochloride using hydrochloric acid in ethanol in Reference Example 9, ¶ [0191].
With respect to claim 8, Schaper expressly performs the isothiuronium/isooxazoline coupling in the present of a strongly basic aqueous alkali-metal or alkaline-ether-metal hydroxide, preferably sodium or potassium. (See ¶ [0042], p. 4). Uchida-2007 likewise teaches sodium hydroxide or other bases for the sulfur-coupling reaction.
With respect to claim 9 and 10, Uchida expressly teaches water, methanol, ethanol, DMF, DMAc, NMP, propylene carbonate, ethers, and hydrocarbon solvents, individually or in mixtures, and particularly favors water or alcohols. (See ¶ [0166]-0168], p. 8). Selection of a polar solvent from the claimed conventional solvent classes therefore would have been obvious for carrying out the known reaction.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Schaper et al. (US2007/0015805 A1) in view of Uchida (US2007/0185324 A1, cited herein as “Uchida-2007”) and Uchida (US2023/0012374 A1, cited as “Uchida-2023”) as applied to claims 4-10 and 21, in further view of Mittal et al. (WO2020/240392 A1).
The teachings of Schaper, Uchida-2007, and Uchida-2023 have been discussed above.
Schaper, Uchida-2007, and Uchida-2023 collectively do not teach in step c) the compound of formula (IV) is alkoxylated using an alkoxylating agent in presence of an alcohol to obtain compound of formula (Va) followed by treatment with an acid to obtain compound of Formula (V).
Mittal teaches an integrated continuous-flow process for preparing pyroxasulfone from the same 1-methyl-3-(trifluoromethyl)-1H-pyrazol-5-ol framework. Specifically, Step A reacts 1-methyl-3-(trifluoromethyl)-1H-pyrozol-5-ol (Formula V) with formaldehyde in the presence of a base to obtain the 4-(hydroxymethyl) Formula VI intermediate (p. 7, ll. 1-8; see also Example 5, p. 20, ll. 1-10; step B reacts Formula VI with chlorodifluoromethane in the presence of base to obtain the corresponding 5-(difluoromethoxy) pyrazol-4-ylmethanol of Formula II (p. 7, ll. 9-13;Example 5, p. 20, ll. 6-11); Step C converts the hydroxymethyl group of Formula VII to the chloromethyl compound of Formula VIII using a chlorinating agent (pp. 7, 9-10; Example 6, p. 20, ll. 12-19); Step D reacts Formula VIII with 5,5-dimethyl-4,5-dihydroisoxazol-3-yl carbamimidothioate (Formula IX) in the present of base to obtain the corresponding pyrazole/isooxazoline sulfide of Formula X (p. 8, ll. 1-12; p. 10, ii. 10-24; Example 7, pp. 20-21); and Step E oxidizes Formula X with sodium tungstate and oxidizing agent, preferably hydrogen peroxide, to obtain pyroxasulfone (p. 8, ll. 10-14; p. 12, ll. 7-17; Example 8, p. 21, ll. 6-14).
Mittal further teaches suitable inorganic bases including potassium methoxide, sodium methoxide, potassium ethoxide, and sodium ethoxide (pp. 11-12, particularly p. 11, ll. 27-32 continuing onto p. 12), and teaches suitable polar protic solvent systems including water and alcohols, expressly identifying methanol, ethanol, n-propanol, n-butanol, 2-butanol, tert-butyl alcohol and other alcohols (pp. 10-11, particularly p. 10, ll. 24-30 through p. 11, ll. 1-8).
The combined references do not expressly describe the precise Formula IV → Formula Va → Formula V sequence by first alkoxylating the 5-fluoro Formula VI compound and subsequently treating Formula Va with acid. This difference is expressly acknowledged.
Nevertheless, it would have been obvious to investigate and employ the alkoxide/alcohol chemistry taught by Mittal in carrying out the conversion of the closely corresponding halogenated/hydroxy pyrazole intermediates of the primary combination because Mittal is directed to preparation of the same ultimate compound, pyroxasulfone, from the same 1-methyl-3-trifluoromethylpyrazole framework and identifies alkali-metal metoxides/ethoxides and alcohol media as suitable reagents/conditions in that chemistry.
One of ordinary skill would have had reason to employ such alkoxide/alcohol conditions as an alternative route for functionalizing the 5-position of the pyrazole intermediate while retaining the remainder of the known pyrazole/isooxazoline scaffold, followed by acidic treatment to obtain the corresponding hydroxy intermediate for further processing.
A reasonable expectation of success would have arisen from the close structural correspondence of the substrates, the known reactivity of the pyrazole, intermediates disclosed by the references and Mittal’s express use of alkoxide bases in the same pyroxasulfone process environment.
Claims 12-18 are rejected under 35 U.S.C. 103 as being unpatentable over Schaper et al. (US2007/0015805 A1) in view of Uchida (US2007/0185324 A1, cited herein as “Uchida-2007”) and Uchida (US2023/0012374 A1, cited as “Uchida-2023”) as applied to claims 4-10 and 21, in further view of Mittal et al. (WO2020/240392 A1).
The teachings of Schaper, Uchida-2007, and Uchida-2023 have been discussed above.
Schaper, Uchida-2007, and Uchida-2023 collectively do not teach oxidation is carried out in presence of an oxidizing agent as recited in claim 12. However, Schaper expressly teaches that the thioether compounds obtained by its process may, if required, be oxidized by reactions known to those skilled in the art. (See ¶ [0047], p. 4.)
Mittal provides the particularly pertinent oxidation conditions., Specifically Step E teaches reacting Formula X-the corresponding 3-(((5-difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)methyl)hito)-5,5-dimethyl-4,5-dihydroisoxazole-with sodium tungstate and an oxidizing agent, particularly hydrogen peroxide, to obtain Formula I, pyroxasulfone (p. 12, approximately ll. 7-17). Example 8 actually carries out this oxidation using sodium tungstate and aqueous hydrogen peroxide at 100oC to yield pyroxasulfone. (See p. 21, approximately ll. 6-14).
It therefore would have been obvious to one of ordinary skill in the art to carry out the oxidation step of the combined processes in the presence of an oxidizing agent as taught by Mittal because Schaper expressly contemplates subsequent oxidation of the thioether’ while Mittal teaches oxidation of the corresponding pyrazole/isooxazoline sulfate substrate to the same desired pyroxasulfone product. A reasonable expectation of success would have existed because Mttal experimentally demonstrates the claimed type of sulfite-to-sulfone conversion on the pertinent substrate.
With regard to claim 13, Schaper, Uchida-2007, and Uchida-2023 collectively do not teach the oxidizing agent is an organic peroxides compound selected from m-chloroperbenzoic acid, performic acid, peracetic acid;inorganic peroxides such as hydrogen peroxide, potassium permanganate, sodium periodate or potassium peroxymonosulfate.
However, Uchida-2023 teaches that oxidation of the compound of formula (4) to the corresponding sulfone of Formula (5) may be conducted using oxidizing agents including hydrogen peroxide, hypochlorite, peroxide, permanganate, manganese dioxide, chromic acid, sodium peroxodisulfate, and potassium peroxymonosulfate (Oxone®). (See ¶¶ [0431] -(0433]). Thus, Uchida-2023 expressly teaches oxidiaing agent falling within the alternatives recited in claim 13.
It would have been obvious to employ such an oxidizing agent in carrying out the oxidation step of the combined processes because Uchida-2023 expressly taches these oxidizing agents for oxidation of the corresponding pyrazole/isooxazoline sulfide to its sulfone.
Regarding clam 14, Uchida-2007, and Uchida-2023 collectively do not teach the oxidizing agent is potassium peroxymonsulfate.
However, Uchida-2023 expressly teaches potassium peroxymonsulfate (Oxone®) as an oxidizing agent that may be employed in place of hydrogen peroxide in the Formula (4)-to-Formula (5) oxidation. (See ¶ [0432]).
Accordingly, it would have been obvious to employ potassium peroxymonosulfate as the oxidizing agent in the oxidation step because Uchida-2023 expressly identifies potassium peroxymonosulfate as an equivalent oxidizing agent for carrying out the same sulfide-to-sulfone transformation.
A person of ordinary skill in the art would have had a reasonable expectation of success because Uchida-2023 expressly teaches potassium peroxymonosulfate as an alternative for performing that very oxidation.
Regarding claim 15, Uchida-2023 expressly teaches that Step iii, which converts the compound of Formula (4) to the compound of Formula (5) by oxidation, is conducted “in the presence of a metal catalyst” (¶ [0431]), and further teaches as a preferred embodiment reacting Formula (4) with hydrogen peroxide in the presence of a metal catalyst. (See ¶ [0433]). Thus, the metal-catalyst limitation of claim 15 is expressly taught by Uchida-2023
Regarding claim 16, Uchida-2007, and Uchida-2023 collectively do not teach metal catalyst is selected from group comprising of tungsten catalyst, molybdenum catalyst, titanium catalyst, zirconium catalyst or mixture thereof.
However, Uchida-2023 further provides a specific species falling within the metal-catalyst genus by expressly employing sodium tungstate in its Formula X-to-Pyroxasulfone oxidation (Step E, p. 12, approximately ll. 7-17; Example 8, p. 21, approximately ll. 6-14). Sodium tungstate is a tungsten catalyst and therefore falls within the “tungsten catalyst” alternative recited in claim 16.
It would have been obvious to employ the expressly taught sodium tungstate catalyst because Mittal actually employs sodium tungstate in oxidation of the corresponding Formula X sulfide to the same final product, pyroxasuflone, thereby providing a reasonably expectation that the catalyst would successfully facilitate the claimed oxidation.
Regarding claim 17, Uchida-2007, and Uchida-2023 collectively do not teach oxidation is carried out in presence of a suitable solvent selected from group comprising of halogenated hydrocarbon; ethers; amides;alcohols; ketones; nitriles; carboxylic acids; water or mixtures thereof.
However, Uchida-2023 expressly teaches solvents suitable for carrying out the oxidation reaction Step iii. Specifically, Uchida-2023 teaches that the reaction may be performed in the presence of an organic solvent and/or water and identifies suitable organic solvents including aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, alcohols, ketones, ethers, esters, amides, nitriles, sulfoxides, and sulfones. (See ¶¶ [0500]-[0524], pp. 46-48). Uchida-2023 further provides specific examples within these classes, including dichloromethane and chloroform as halogenate hydrocarbons, methanol, ethanol, 2-propanol, and butanol as alcohols; acetone and methyl ethyl ketones as ketones; tetrahydrofuran and other ethers; N, N-dimethylformamide and N,N-dimethylacetamine as amides; and acetonitrile as nitrile. Uchida-2023 further teaches that the reaction solvent may comprise water and that water may be used in combination with organic solvent. Accordingly, the solvent limitation of claim 17 is expressly taught by Uchida-2023. It would have been obvious to one of ordinary skill in the art to conduct the oxidation step of the combined processes in one of the solvents taught by Uchida-2023 because Uchida-2023 expressly identifies these solvents as suitable reaction media for the same step iii sulfide-to-sulfone oxidation. A reasonable expectation of success would have existed because Uchida-2023 teaches the solvents specifically for carrying out that oxidation reaction, rather merely as solvents generally useful in pyroxasulfone synthesis.
Regarding claim 18, Uchida-2007, and Uchida-2023 collectively do not teach the method
further comprises a process for purification of Pyroxasulfone comprising treating Pyroxasulfone with mixture of alcohol and water at temperature ranging from 50°C to 110°C.
However, Uchida-2023 further teaches purification and crystallization of pyroxasulfone. Uchida-2023 teaches that the product obtained from the process may be subjected to working-up-procedures including washing with water, washing with organic solvent, suspension in an organic solvent, recrystallization and crystallization, and further teaches that these procedures may approximately be combined and repeated. (See ¶¶ [0418]-[0428], pp. 41-42). Uchida-2023 further teaches crystallization/purification of pyroxasulfone from a liquid medium comprising an organic solvent and water and identifies water-miscible organic acid solvents, including C1-C4 alcohols such as methanol, ethanol, 2-propanol and butanol, as suitable organic solvents for such purification/crystallization. (See ¶¶ [0589]-[0600], pp. 52-53). Uchida-2023 therefore teaches purification of pyroxasulfone using alcohol/water medium. Although Uchida-2023 does not appear to expressly recite Applicant’s entire temperature range of “50oC to 110oC” in the same sentence describing the alcohol/water purification medium, UIchida-2023 teaches heating and cooling in connection with dissolution, crystallization and isolation of pyroxasulfone and employs elevated temperatures within the claimed range in processing the corresponding pyroxasulfone-containing mixtures.
It would have been obvious to one of ordinary skill in the art to conduct the alcohol/water purification taught by Uchida-2023 at a temperature within the claimed range of 50oC to 110oC because temperature is conventional result-effective process parameter in dissolution/recrystallization, and the skilled artisan would have selected a temperature sufficient to dissolve or suspend the pyroxasulfone in the taught alcohol/water medium, followed by cooling and/or adjustment of the solvent composition to effect crystallization and recovery of the purified product. The selection of a temperature within the claimed range would have involved routine optimization of the expressly taught purification/crystallization process according to solubility and crystallization behavior.
A reasonably expectation of success would have existed because Uchida-2023 expressly teaches purification/crystallization of pyroxasulfone using water-containing organic-solvent media, including alcohols, and teaches dissolution/crystallization procedures for recovering purified pyroxasulfone.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
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Claims 3-10, 12-18, and 21 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 7 and/or 14 of copending Application No. 19/166,351 in view of Schaper et al. (US 2007/0015805 A1), Uchida et al. (US 2007/0185334 A1), Uchida et al. (US 2023/0012374 A1), and Mittal et al. (WO 2020/240392 A1), as applicable.
Claim 7 of the reference application depends from claim 1 and requires the specifically claimed Formula III difluoromethoxy pyrazole intermediate to be further used for preparing Pyroxasulfone of Formula VII.
More particularly, reference claim 1 prepares Formula III by reacting the corresponding 5-hydroxy-1-methyl-3-(trifluoromethyl) pyrazole Formula II compound with chlorodifluoromethane, and reference claim 7 expressly requires subsequent use of that resulting Formula III intermediate in preparation of Pyroxasulfone.
Reference claim 14 provides an even more pertinent process claim. Through its dependency from claim 13, claim 14 requires:
1. Formula II → Formula III using chlorodifluoromethane; 2. Formula III → Formula I using paraformaldehyde and a chlorinating agent; 3. condensation of Formula I, or a derivative thereof, with a suitable isoxazoline compound to obtain Formula VI; and 4. oxidation of Formula VI to obtain Pyroxasulfone of Formula VII.
Thus, reference claim 14 already claims an integrated process beginning with the same 5-hydroxy/trifluoromethyl pyrazole framework, introducing the difluoromethoxy functionality, producing a functionalized pyrazole intermediate, coupling that intermediate with an isoxazoline component, and ultimately oxidizing the resulting sulfur-containing intermediate to the same Pyroxasulfone product.
Instant claims 3 and 4
Instant claim 3 requires condensing its Formula II compound with thiourea to obtain the instant Formula I isothiuronium compound or salt thereof, followed by converting that compound to Pyroxasulfone.
Instant claim 4 more particularly requires:
Formula II + thiourea → instant Formula I → Formula IV → Formula V → Formula VI → Pyroxasulfone.
Reference claim 14 does not expressly recite preparation and use of the particular isothiuronium Formula I intermediate of instant claims 3–4 and does not expressly recite the identical sequence of intermediates IV and V employed by instant claim 4.
However, those differences would not have rendered the instant claimed process patentably distinct.
Schaper expressly teaches preparation of isothiuronium salts by reacting the corresponding alkylating agent with thiourea and subsequent use of those isothiuronium salts in preparing the sulfur-linked isoxazoline compounds. Schaper further teaches that the mercaptan formed from the isothiuronium salt may be generated in situ and immediately reacted with the isoxazoline reagent. Significantly, Schaper’s Synthesis Example C applies this chemistry to the particularly pertinent 5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl) methyl system and 3-chloro-5,5-dimethyl-4,5-dihydroisoxazole. Compound 35 of Table A identifies the corresponding difluoromethoxy/trifluoromethyl pyrazole-isoxazoline thioether species. Schaper additionally teaches that the resulting compounds may subsequently be oxidized.
Uchida 2007 likewise teaches the pertinent thiourea/isothiuronium chemistry and preparation/use of the corresponding isoxazoline thiocarboxamidine in the 5-hydroxy-1-methyl-3-trifluoromethylpyrazole environment.
It therefore would have been obvious to one of ordinary skill in the art, starting with the pyroxasulfone-producing process claimed in reference claim 14, to employ the known thiourea/isothiuronium route taught by Schaper and Uchida for constructing the sulfur linkage between the pyrazole and isoxazoline portions of the molecule. The references concern closely corresponding intermediates used for preparation of the same pyroxasulfone structural framework and teach the alternative sulfur-coupling chemistry for its known purpose.
A reasonable expectation of success would have existed because Schaper experimentally demonstrates the pertinent chemistry on the difluoromethoxy/trifluoromethyl pyrazole-isoxazoline scaffold itself.
Accordingly, the processes of instant claims 3 and 4 would have been obvious variations of the pyrosulfate preparation claimed in reference claim 14.
Instant claims 5–10
Claims 5–10 further specify conventional conditions associated with the thiourea/isothiuronium formation and sulfur-coupling portions of instant claim 4.
Regarding claims 5 and 6, Schaper teaches preparing the isothiuronium salts from the corresponding alkylating agent and thiourea in inert organic solvents, expressly including lower alcohols such as methanol, ethanol and isopropanol; hydrocarbons such as benzene and toluene; halogenated hydrocarbons such as dichloromethane and chloroform; and ethers such as methyl tert-butyl ether, tetrahydrofuran and dioxane.
Regarding claim 7, Uchida 2007 teaches preparation of the pertinent isoxazoline thiocarboxamidine hydrochloride under acidic conditions.
Regarding claim 8, Schaper expressly teaches conducting the isothiuronium/isoxazoline reaction in the presence of an aqueous, strongly basic alkali-metal or alkaline-earth-metal hydroxide, preferably sodium or potassium hydroxide.
Regarding claims 9 and 10, the cited references teach polar reaction media including alcohols, water, ethers, acetonitrile and amide solvents for the corresponding sulfur chemistry.
Accordingly, selection of the solvents, acid/base conditions and polar reaction media recited in instant claims 5–10 would have constituted the predictable use of known reaction conditions in carrying out the process that is otherwise not patentably distinct from reference claim 14.
Instant claims 12–14 — oxidizing agent
Reference claim 14 itself, requires oxidizing the sulfur-containing Formula VI intermediate to obtain Pyroxasulfone.
Instant claim 12 further specifies that this oxidation is carried out in the presence of an oxidizing agent. Uchida 2023 expressly teaches that its corresponding Step iii converts the sulfide of Formula (4) to the sulfone of Formula (5) by oxidation.
For claims 13 and 14, Uchida 2023 ¶[0432] identifies suitable oxidizing agents including hydrogen peroxide, hypochlorite, peroxide, permanganate, manganese dioxide and chromic acid and expressly teaches potassium peroxymonosulfate (Oxone®) as an alternative to hydrogen peroxide for carrying out the oxidation.
Accordingly, employing an oxidizing agent as recited in claim 12, including the species encompassed by claim 13 and particularly potassium peroxymonosulfate as required by claim 14, would have been an obvious manner of carrying out the oxidation already positively required by reference claim 14. The artisan would have reasonably expected success because Uchida expressly teaches those oxidants for the corresponding sulfide-to-sulfone transformation.
Instant claims 15 and 16 — metal catalyst Instant claim 15 requires that the oxidation be performed in the presence of a metal catalyst and claim 16 identifies catalyst classes including a tungsten catalyst.
Uchida 2023 expressly teaches that the corresponding sulfide-to-sulfone oxidation is conducted in the presence of a metal catalyst (¶¶[0431], [0433]).
Mittal is even more specific. Its Step E converts the corresponding Formula X pyrazole/isoxazoline sulfide to Pyroxasulfone using sodium tungstate and an oxidizing agent, preferably hydrogen peroxide. Example 8 actually performs that conversion using sodium tungstate and aqueous hydrogen peroxide at 100°C. Thus, use of a metal catalyst as recited in instant claim 15, and specifically a tungsten catalyst as encompassed by claim 16, would have been an obvious implementation of the oxidation already required by reference claim 14. A reasonable expectation of success is established by Mittal’s actual oxidation of the corresponding sulfide to the same Pyroxasulfone product using sodium tungstate.
Instant claim 17 — oxidation solvent
Instant claim 17 further requires that the oxidation be conducted in a suitable solvent selected from the recited classes.
Uchida 2023 expressly addresses “Reaction Solvent in Step iii” and teaches that the corresponding oxidation may be conducted in an organic solvent and/or water. Its solvent disclosure encompasses halogenated hydrocarbons, ethers, amides, alcohols, ketones, nitriles and water, among other solvents (¶¶[0500]–[0524], pp. 46–48). Consistently, Uchida’s own claim 17 expressly identifies aromatic hydrocarbons, halogenated hydrocarbons, ethers, ketones, amides and nitriles as suitable organic solvents for the oxidation, while its claim 18 expressly provides for carrying out the reaction in the presence of water.
Accordingly, carrying out the oxidation required by reference claim 14 in a solvent encompassed by instant claim 17 would have been an obvious selection of a reaction medium expressly taught for that oxidation, with a reasonable expectation of success.
Instant claim 18 — purification
Instant claim 18 further adds purification of the resulting Pyroxasulfone by treatment with a mixture of alcohol and water at 50°C to 110°C.
Uchida 2023 expressly teaches working-up, isolation and purification of the oxidation product by procedures including washing with water, washing with organic solvent, suspension in organic solvent, recrystallization and crystallization, and further teaches that such procedures may be combined and repeated (¶¶[0419]–[0428], pp. 41–42). Uchida further teaches Pyroxasulfone purification/crystallization using a liquid medium comprising an organic solvent and water and identifies water-miscible organic solvents including alcohols such as methanol, ethanol, 2-propanol and butanol (¶¶[0589]–[0600], pp. 52–53). Uchida additionally teaches controlled addition of water during product recovery. Uchida does not appear to expressly associate the entire claimed 50°C–110°C range with that alcohol/water purification in a single disclosure. Nevertheless, once purification/crystallization of Pyroxasulfone from the expressly taught alcohol/water medium was selected, adjustment of the temperature to facilitate dissolution followed by crystallization would have been an ordinary process optimization based on the known temperature-dependent solubility of the product in the selected solvent system.
Thus, the added purification limitation of instant claim 18 does not render the process patentably distinct from the pyroxasulfone process of reference claim 14 when considered with Uchida’s express purification teachings.
Instant claim 21
Instant claim 21 broadly recites:
“A method of using compound of formula (I) or its salt, in the process for preparation of Pyroxasulfone of formula (VII).”
Reference claim 7 expressly claims use of its difluoromethoxy pyrazole Formula III intermediate for preparing Pyroxasulfone, while reference claim 14 expressly claims subsequent conversion of the functionalized pyrazole intermediate through isoxazoline coupling and oxidation to Pyroxasulfone.
Although the particular intermediate recited in instant claim 21 is the instant isothiuronium Formula I compound, Schaper and Uchida 2007 establish the known use of the corresponding thiourea/isothiuronium chemistry to construct the sulfur-linked pyrazole/isoxazoline intermediate in the route to the same pyroxasulfone framework. Schaper’s Example C is especially pertinent because it employs the difluoromethoxy/trifluoromethyl pyrazole scaffold.
It therefore would have been obvious to use the known isothiuronium intermediate as the sulfur-transfer/coupling precursor in carrying out the pyroxasulfone preparation encompassed by reference claims 7 and 14. Accordingly, the subject matter of instant claim 21 is not patentably distinct from the subject matter claimed in the reference application when considered with the pertinent teachings of Schaper and Uchida.
This is a provisional nonstatutory double patenting rejection.
Conclusion
Claims 3-18 and 21 are not allowed.
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/JEAN P CORNET/Primary Examiner, Art Unit 1628
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