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 without traverse of group II, drawn to the apparatus claims, in the reply filed on 02/27/2026 is acknowledged.
Claims 23-25 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 02/27/2026.
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.
Claims 11 and 12 are rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor regards as the invention.
Regarding claims 11 and 12, claims 11 and 12 recite the limitation “the redox catalyst”. There is insufficient antecedent basis for this limitation in the claims.
Specifically, claim 1 recites “a heterogeneous redox catalyst”, but not “a redox catalyst”. It is therefore unclear whether the limitation “the redox catalyst” is intended to refer to “the heterogeneous redox catalyst”, or whether “the redox catalyst” is intended to recite an additional “redox catalyst”.
Claims 11 and 12 are therefore indefinite.
Examiner recommends amending claims 11 and 12 to recite “the heterogeneous redox catalyst”.
In the interest of compact prosecution, it is further noted that claim 24, currently withdrawn from consideration, also recites “the redox catalyst”.
Claim Rejections - 35 USC § 103
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-16 and 19-22 are rejected under 35 U.S.C. 103 as being unpatentable over Stahl (US Pat. Pub. 2018/0358642 A1) in view of Perkins et al. (“Metal-Reductant-Free Electrochemical Nickel-Catalyzed Couplings of Aryl and Alkyl Bromides in Acetonitrile” Org. Process Res. Dev. 2019, 23, 1746−1751 and SI).
Regarding claim 1, Stahl teaches an electrosynthetic cell (“the electrochemical cell is … an electrosynthetic cell” para. 32) for use in a reductive electrosynthesis of one or more desired chemical products from one or more chemical reactants (“anode half-cells can be used in … electrosynthetic cells that produce one or more desired chemical products,” abstract and see Fig. 6) the electrosynthetic cell comprising:
a hydrogen anode half-cell (“a flow anode using anthraquinone-2,7-disulfonic acid, disodium salt as the redox mediator and H2 as fuel” para. 48 and Fig. 6, see also paras. 19 and 82) and a cathode half-cell (“regenerative redox cathode using O2 as the oxidant.” Para. 86 and Fig. 6), wherein the hydrogen anode half-cell comprises:
hydrogen (H2) (“H2 as fuel” para. 48 and Fig. 6);
a first liquid phase solution that is in contact with an anode (“1 M H2SO4” para. 82, “the anode contains an aqueous solution containing a dissolved carbon-containing redox mediator and a heterogeneous redox catalyst,” para. 62, and Fig. 6) and a heterogeneous redox catalyst capable of catalyzing the oxidation of H2 to H+, wherein the heterogeneous redox catalyst is not affixed to the anode (“a heterogeneous redox catalyst, which can oxidize the fuel and is not in direct contact with the anode.” para. 62 and “H2 as fuel” para. 48); and
a redox mediator (“anthraquinone-2,7-disulfonic acid” para. 82), wherein the redox mediator is capable of transferring or accepting electrons and/or protons while undergoing reduction or oxidation (see e.g., Fig. 2); and
wherein the cathode half-cell comprises:
a second liquid phase solution (“1 M H2SO4” para. 87) in contact with a cathode (see Fig. 6).
Stahl does not explicitly teach the second liquid phase solution comprises the one or more chemical reactants and is in contact with a reductive synthesis catalyst capable of catalyzing the reductive synthesis of the one or more desired chemical products from the one or more chemical reactants. While Stahl teaches the system is suitable for the reductive electrosynthesis of products, no detailed examples of this configuration are provided.
However, Perkins teaches an electrosynthetic cell (see e.g., abstract) for use in a reductive electrosynthesis of one or more desired chemical products from one or more chemical reactants (“nickel-catalyzed reductive cross-coupling of aryl bromides with alkyl bromides” abstract) comprising a cathode-half cell (“cathodic chamber” e.g., Table 1, partially reproduced below) which comprises a liquid phase solution (“MeCN” Table 1),
the liquid phase solution comprising the one or more chemical reactants (“Alkyl bromide (1.3 equiv) and aryl bromide (6.5 mmol, 1.0 equiv) were added to the cathodic chamber” § S3.1, and see Table 1), wherein
the liquid phase solution is in contact with a cathode (“an RVC [reticulated vitreous carbon] electrode” Table 1 caption and § S3.1) and a reductive synthesis catalyst capable of catalyzing the reductive synthesis of the one or more desired chemical products from the one or more chemical reactants (“[Ni] (10 mol %), L1 (8 mol %), L2 (2 mol %)” Table 1, see also § S3.1).
As Stahl and Perkins each teach electrosynthetic cells for use in a reductive electrosynthesis of one or more desired chemical products from one or more chemical reactants, Stahl and Perkins are analogous art to the instant invention.
It would therefore have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to modify the system of Stahl, such that the second liquid phase solution comprises the one or more chemical reactants and is in contact with the cathode and a reductive synthesis catalyst capable of catalyzing the reductive synthesis of the one or more desired chemical products from the one or more chemical reactants, as taught by Perkins. A person having ordinary skill in the art would have been motivated to make this modification because Stahl suggests using the system for reductive electrosynthesis, and Perkins teaches including the one or more chemical reactants and a reductive synthesis catalyst capable of catalyzing the reductive synthesis of the one or more desired chemical products from the one or more chemical reactants in the catholyte i.e., the second liquid phase solution, is an effective means of configuring an electrosynthetic cell for use in a reductive electrosynthesis. Furthermore, simple substitution of one known element for another (i.e., using the catholyte system of Perkins in place of the catholyte system of Stahl) to achieve predictable results (forming a complete electrosynthesis cell for a reductive electrosynthesis) establishes a prima facie case of obviousness (MPEP § 2143(I)(B)).
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Partial Perkins Table 1
Regarding claim 2, modified Stahl further teaches, via Perkins, the one or more chemical reactants comprise a first chemical reactant that is an aryl halide (“ArBr starting material 1” p. 1747 col. 1 para. 3 and see Table 1 and Scheme 2) or heteroaryl halide (“7i, 7j” Scheme 2), and the second chemical reactant is an alkyl halide (“alkyl bromide 2” para. bridging p. 1748 col. 2 and p. 1749 col. 1, and see Table 1 and Scheme 2), a cycloalkyl halide (“9e” Scheme 2), or a heterocycloalkyl halide (“9f, 9g” Scheme 2).
Regarding claim 3, modified Stahl further teaches, via Perkins, the molar ratio of the first chemical reactant to the second chemical reactant is 1:1.3, a value within the claimed range (“1.3 equiv of alkyl bromide” Scheme 2 caption, see also Table 1 and § titled “Procedure” on p. 1749).
Regarding claims 4 and 5, as currently drafted claims 4 and 5 are rendered optional by use of the word “optionally”. Under the broadest reasonable interpretation, optional limitations do not further narrow the scope of a claim (MPEP § 2111.04).
Therefore, as modified Stahl renders the limitations of claim 2 obvious, modified Stahl also renders the limitations of claims 4 and 5 obvious.
Regarding claim 6, modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches the redox mediator is dissolved within the first liquid phase solution and is capable of moving between the anode and the redox catalyst (“the redox mediator is dissolved within the electrolyte solution and is capable of moving between the electrode and the heterogeneous redox catalyst” para. 18 and Fig. 1, see also para. 59) and wherein the electrosynthetic cell is configured to reduce an oxidized form of the redox mediator at the redox catalyst and oxidize a reduced form of the redox mediator at the anode (“the reduced form of the redox mediator is being oxidized at the anode electrode, and the oxidized form of the redox mediator is being reduced at the heterogeneous redox catalyst” para. 21 and Fig. 1, see also para. 59).
Regarding claim 7, modified Stahl renders the limitations of claim 6 obvious, as described above.
Stahl further teaches the reduced form of the redox mediator is selected from the group consisting of 1,4-dihydroxybenzene (“the reduced form of the redox mediator is selected from a substituted dihydroxybenzene … Preferential substitution of the hydroxyl groups on the dihydroxybenzene include 1,2- and 1,4-substitution” para. 64), and 9,10-dihydroxyanthracene (“Exemplary redox mediators where the reduced form is a substituted dihydroxybenzene include, without limitation, anthrahydroquinone-2,7 -disulfonic acid, 1,8-dihydroxy-anthrahydroquinone-2,7-disulfonic acid, anthrahydroquinone-2-sulfonic acid, or salts thereof.” para. 66, note anthrahydroquinone is the common name for 9,10-dihydroxyanthracene, see Figs. 2 and 3).
Regarding claim 8, modified Stahl renders the limitations of claim 2 obvious, as described above.
Modified Stahl further teaches or, in the alternative, renders obvious, a concentration of the redox mediator that is about 38.5 mol% based on the molar amount of the first chemical reactant (see below), a value within the claimed range.
Stahl teaches the redox mediator has a concentration of 0.1 M (“0.1 M of the anthraquinone disulfonic acid disodium salt” para. 83). Modified Stahl, via Perkins, teaches the first chemical reactant has a concentration of 0.26 M (6.5 mmol scale … 25 mL of MeCN” Table 1 caption). Modified Stahl thus teaches a concentration ratio of about 1:2.6 for the redox mediator relative to the first chemical reactant.
Stahl is silent as to the volumes of the cathode and anode chambers, implying the volumes are equal. Thus, in modified Stahl, the 1:2.6 concentration ratio is equivalent to a 1:2.6 molar ratio, or about 38.5 mol %.
Alternatively, Perkins further teaches the cathode and anode chambers have equal volumes (“Each chamber contained an RVC electrode and 25 mL of MeCN.” Table 1 caption). Therefore, a person having ordinary skill in the art would have found it obvious, when modifying the system of Stahl, to do so such that the volumes of the cathode and anode chambers are equal, and therefore such that the molar ratio of redox mediator to the first chemical reactant is 1:2.6, or about 38.5 mol %.
Regarding claim 9, modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches the redox mediator has a concentration of 100 mM in the first liquid phase solution (“0.1 M of the anthraquinone disulfonic acid disodium salt” para. 83), a value within the claimed range.
Regarding claim 10, claim 10 has been interpreted as “the heterogeneous redox catalyst”.
Modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches the heterogeneous redox catalyst comprises Pt (“a redox catalyst consisting of Pt supported on carbon (Pt/C).” para. 83).
Regarding claim 11, claim 11 has been interpreted as “the heterogeneous redox catalyst”.
Modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches the redox catalyst is 0.5 mol % based on the molar amount of the redox mediator, a value close to the claimed range (at least 1 mol %). A value in the prior art close to a claimed range establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Regarding claim 12, modified Stahl renders the limitations of claim 1 obvious, as described above.
Modified Stahl further teaches, via Perkins, the second liquid phase solution of the cathode half-cell is acetonitrile (MeCN) (“Each chamber contained an RVC electrode and 25 mL of MeCN.” Table 1 caption).
Regarding claim 13, modified Stahl renders the limitations of claim 1 obvious, as described above.
Modified Stahl further teaches, via Perkins, the second liquid phase solution of the cathode half-cell comprises a supporting electrolyte of tetrabutylammonium hexafluorophosphate (NBu4PF6) or tetrabutylammonium tetrafluoroborate (NBu4BF4) (“it appears that the cation Bu4N+ is essential (Table 1, entries 1 and 10), but PF6- could be replaced with another noncoordinating counterion, BF4- (entry 11).” P. 1747 col. 2 para. 1 and Table 1).
Regarding claim 14, modified Stahl renders the limitations of claim 1 obvious, as described above.
Modified Stahl further teaches, via Perkins, the reductive synthesis catalyst comprises Ni (“[Ni] (10 mol %)” Table 1, see also Scheme 2 and title) and the ligands 4,4'-di-tert-butyl-2,2- dipyridyl (dtbbpy) and 4,4,',4"-tri-tert-butyl-2,2':6',2"-terpyridine (ttbtpy) (“While 4,4’-di-tert-butyl-2,2’-bipyridine (L2) alone was a poor ligand (entry 3), 4,4’,4”-tri-tert-butyl-2,2’:6’,2’-terpyridine (L1) [sic] alone (entry 2) or combined with a small amount of L2 provided reasonable yields of the product (entries 1 and 4).” p. 1747 col. 1 para. 2 and Table 1, see also abstract).
Regarding claim 15, modified Stahl further teaches, via Perkins, the one or more ligands comprise dtbbpy and ttbtpy (“the use of a combination of the ligands 4,4’,4”-tri-tert-butyl-2,2’:6’,2’-terpyridine [sic] and 4,4’-di-tertbutyl-2,2’-bipyridine is essential to achieve high yields” abstract, see also p. 1747 col. 1 para. 2 and Table 1), and
the ratio of dtbbpy to ttbtpy is 1:2 (“2:1 L1:L2” Table 1 i.e., 2:1 [ttbtpy]:[dtbbpy]), 1:1, 2:1, or 4:1 (“L1:L2 = 1:1”, “L1:L2 = 1:2”, and “L1:L2 = 1:4” Scheme 2), values within the claimed range.
Regarding claim 16, modified Stahl renders the limitations of claim 2 obvious, as described above.
Modified Stahl further teaches, via Perkins, the reductive synthesis catalyst is 7 (“NiBr2(dme) (7 mol%)” Scheme 2) or 10 mol % (“[Ni] (10 mol%)” Table 1), based on the molar amount of the first chemical reactant, values within the claimed range.
Regarding claim 19, modified Stahl renders the limitations of claim 1 obvious, as described above.
Modified Stahl further teaches, via Perkins, the cathode half-cell further comprises one or more desired chemical products and the one or more desired chemical products comprise a reductive C(sp2)-C(sp3) coupled product (“3” Table 1, see also abstract and Scheme 2).
Regarding claim 20, modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches a device capable of applying an external electromotive force to the anode and the cathode to remove electrons from the anode and to add electrons to the cathode (“In the operation of the anode half-cell in an electrolytic cell, an external electromotive force (EMF) removes electrons from the anode electrode, …” (para. 60 and see Fig. 1).
Regarding claim 21, modified Stahl renders the limitations of claim 1 obvious, as described above.
The limitation “wherein the external electromotive force has a current density of from 0.01 mA cm-2 to 20 mA cm-2”, as currently drafted, is a functional recitation i.e., it defines the apparatus by what it does, rather than what it is. For apparatus claims, the broadest reasonable interpretation of a functional limitation is an apparatus capable of performing the recited function (MPEP § 2114).
In the instant case, modified Stahl teaches, via Perkins, the current density is about 3.6 mA/cm2, a value within the claimed range (see calculations below). The system is therefore capable of applying a current density of about 3.6 mA cm-2, a value within the claimed range. Modified Stahl therefore renders the limitation “wherein the external electromotive force has a current density of from 0.01 mA cm-2 to 20 mA cm-2” obvious.
Calculations: Perkins teaches a constant current of 25 mA is applied (Table 1 caption), and the submerged area of the electrode is 1.5 x 1.0 x 1.0 cm (§ 2 and Fig. S2). The total external surface area of the electrode is thus (1cm*1cm)*1 face + (1.5cm*1cm)*4 faces = 7 cm2.
Regarding claim 22, modified Stahl renders the limitations of claim 1 obvious, as described above.
Stahl further teaches an anion exchange membrane or a cation exchange membrane separating the hydrogen anode half-cell and the cathode half-cell (“The anode and cathode are separated by a permeable membrane. If the anode solution (and cathode solution, if a redox cathode is used) is acidic, a proton-exchange membrane should be used, and if the solution(s) are basic, an anion-exchange membrane should be used.” para. 62).
Allowable Subject Matter
Claims 17 and 18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding claim 17, the prior art, alone or in combination, does not reasonably teach or render obvious the cumulative limitations of claim 17, with a particular emphasis on the combination of the limitations “the one or more chemical reactants comprise a first chemical reactant selected from an aryl halide, a heteroaryl halide, an alkenyl halide, or any combination thereof and a second chemical reactant selected from an alkyl halide, a cycloalkyl halide, a heterocycloalkyl halide, or any combination thereof” (claim 2) and “the hydrogen anode half-cell further comprises a base” (claim 17).
The closest prior art is considered to be Stahl (US Pat. Pub. 2018/0358642 A1), Perkins et al. (“Metal-Reductant-Free Electrochemical Nickel-Catalyzed Couplings of Aryl and Alkyl Bromides in Acetonitrile” Org. Process Res. Dev. 2019, 23, 1746−1751 and SI), Murray (US Pat. Pub. 2020/0056291 A1), and Llorente et al. (“Paired Electrolysis in the Simultaneous Production of Synthetic Intermediates and Substrates” J. Am. Chem. Soc. 2016, 138, 15110−15113).
Stahl in view of Perkins is considered to render the limitations of claim 2 obvious, as described above.
However, Stahl does not teach the hydrogen anode half-cell comprises a base. Instead, Stahl teaches the hydrogen anode half-cell comprises an acid (“1 M H2SO4 as supporting electrolyte” para. 81). Given Stahl’s usage of a concentrated acid in the anode half-cell, modifying the half-cell to comprise a base would necessitate replacing the acid in the electrolyte. It is therefore considered that this modification would not be obvious to a person having ordinary skill in the art absent a strong motivation in the prior art.
Perkins teaches an anode half-cell comprising a base i.e., di-isopropyl amine (see Table 1 and p. 1747 col. 1 para. 1), however the base in Perkins is used as the sacrificial reductant, a role that is performed by the hydrogen gas in the system of Stahl. Perkins therefore cannot be considered to provide a motivation to modify the system of Stahl by replacing the acid in the anode half-cell with a base.
Murray teaches an electrosynthetic cell for use in reductive electrosynthesis (abstract), wherein the anode half-cell comprises a base (“the second electrode compartment comprises a solution (e.g., an anolyte solution) that has a relatively high pH.” para. 123). However:
a) the system of Murray uses hydroxide as the sacrificial oxidant rather than hydrogen, as required by the limitations of claim 1 i.e., the anode half-cell of Murray is not a hydrogen anode half-cell comprising hydrogen;
b) while Murray uses anthraquinone as a redox mediator, it does so in the cathode half-cell, and explicitly teaches the catholyte should be maintained under acidic conditions to enhance the redox activity of the anthraquinone mediator (“the reaction of the first electrode compartment takes place at a relatively low pH (e.g., reduction of a quinone into a hydroquinone)” Id.); and
c) while Murray teaches it is advantageous to maintain a pH differential between the anode half-cell and cathode half-cell to reduce the required emf potential, in accordance with the Nernst equation, modifying the system of modified Stahl in the manner would require modifying the cathode half-cell to have a low pH i.e., it would require modifying the system of Perkins to comprise an acid.
Murray therefore cannot be considered to provide a person having ordinary skill in the art with a motivation to modify the system of Stahl by replacing the acid in the anode half-cell with a base.
Llorente teaches an electrosynthetic cell for use in reductive electrosynthesis (see e.g., Fig. 1), wherein the anolyte comprises a redox mediator i.e., Ce(IV) (Id.). However, as with Murray, Llorente teaches an acidic anolyte solution (“5 mM ceric ammonium nitrate (CAN)” p. 15111 para. bridging cols. 1 and 2, as will be understood by a person having ordinary skill in the art CAN is highly acidic). Llorente therefore cannot be considered to provide a person having ordinary skill in the art with a motivation to modify the system of Stahl by replacing the acid in the anode half-cell with a base.
Thus, it is considered that a person having ordinary skill in the art would not have had a motivation to modify the system of Stahl such that the anode half-cell comprises a base. It is therefore considered that the cumulative limitations of claim 17 are patentably distinguished over the prior art. Claim 17 would therefore be allowable if rewritten in independent for, including all limitations of the base and intervening claims.
Regarding claim 18, claim 18 depends from claim 17, and therefore incorporates the patently distinguished subject matter of claim 17. The cumulative limitations of claim 18 are therefore patentably distinguished over the prior art for at least the same reasons as claim 17.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Semenov (US Pat. Pub. 2023/0407492 A1) teaches an electrosynthetic system for the coupling of aryl halides to alkyls using a nickel catalyst, but the alkyls are not alkyl halides and the system is an undivided cell (see e.g., Figs. 2a-d).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALEXANDER R PARENT whose telephone number is (571)270-0948. The examiner can normally be reached M-F 11:00 AM - 6 PM EST.
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/ALEXANDER R. PARENT/Examiner, Art Unit 1795
/ALEXANDER W KEELING/Primary Examiner, Art Unit 1795
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