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 .
This is in response to the Amendment dated January 6, 2026. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Response to Amendment
Claim Objections
Claims 1 and 11 have been objected to because of minor informalities.
The objection of claims 1 and 11 has been withdrawn in view of Applicant’s amendment.
Claim Rejections - 35 USC § 112
Claims 6, 8 and 14 have been 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.
The rejection of claims 6, 8 and 14 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, has been withdrawn in view of Applicant’s amendment.
Claim Rejections - 35 USC § 103
I. Claim(s) 1-7 and 9-16 stand rejected under 35 U.S.C. 103 as being unpatentable over Richter et al. (US Patent Application Publication No. 2008/0110763 A1) in view of Pletcher et al. (“Flow Electrolysis Cells for the Synthetic Organic Chemistry Laboratory,” Chemical Reviews (2017 Sep 18), Vol. 118, No. 9, pp. 4573-4591).
Regarding claim 1, Richter teaches a process for the preparation of a compound of formula (I):
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wherein R is a linear or branched C1-C6 alkyl group (= DHF-alkoxy derivatives of the general formula (IIIa)
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in which R3 is C1-C6-alkyl), wherein the process comprises electrochemically reacting in an electrochemical reactor with a flow (= preferably, it is carried out continuously using undivided flow cells) [page 3, [0051]) the compound of formula (II) in Z-form
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(= from butene-1,4,-diol of the general formula (I)
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(page 1, [0012]), where R1 and R2 in formula (I) are hydrogen) [page 2, [0028] and [0029]] with at least one mono alcohol of formula (III)
ROH (III),
wherein R has the same meaning as in compound of formula (I) [= the C1- to C6-monoalkyl alcohol preferably employed is methanol or isopropanol] (page 1, [0015]).
The method of Richter differs from the instant invention because Richter does not disclose wherein the flow is a vertical flow.
Richter teaches that:
The process according to the invention can be carried out in all customary types of electrolysis cells. Preferably, it is carried out continuously using undivided flow cells. Very particularly suitable are bipolar-switched capillary gap cells or stacked plate cells, in which the electrodes are designed as plates and are arranged plane-parallel (cf. Ullmann's Encyclopedia of Industrial Chemistry, 1999 electronic release, Sixth Edition, VCH-Verlag Weinheim, Volume Electrochemistry, Chapter 3.5. special cell designs, and Chapter 5, Organic Electrochemistry, Subchapter 5.4.3.2 Cell Design). Such electrolysis cells are, for example, also described in DE-A-19533773 (page 3, [0051]).
Pletcher teaches organic electrosynthesis (page 4573, abstract).
Flow cells can lead to much improved performance. Electrolysis is participating in the
trend toward continuous flow synthesis, and this has led to a number of innovations in flow cell
design that make possible selective syntheses with high conversion of reactant to product with a single passage of the reactant solution through the cell (page 4573, abstract).
The laboratory arrangement for electrosynthesis using an undivided flow cell with recycle of reactant solution is:
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(page 4577, Fig. 2(a)).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the flow described by Richter with wherein the flow is a vertical flow because the laboratory arrangement for electrosynthesis using an undivided flow cell with recycle of reactant solution of:
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leads to much improved performance and makes possible selective syntheses with high
conversion of reactant to product with a single passage of the reactant solution through the
cell.
Known work in one field of endeavor may prompt variations of it for use in either the same field or a different field based on the function or property of the known work if the variations are predictable to one of ordinary skill in the art (MPEP § 2141 and § 2141.03).
The motivation to combine prior art references can arise from the expectation that the prior art elements will perform their expected functions to achieve their expected results when combined for their commonly known purpose (MPEP § 2141 and § 2144.07).
Regarding claim 2, Richter teaches wherein R is -CH3 or -CH2CH3 (= in which R3 is C1-C6-alkyl) [page 2, [0029]].
Regarding claim 3, Richter teaches wherein R is -CH3 (= in which R3 is C1-C6-alkyl) [page 2, [0029]].
Regarding claim 4, Richter teaches wherein the process is carried out in a non-aqueous medium (= the C1- to C6-monoalkyl alcohol preferably employed is methanol or isopropanol) [page 1, [0015]].
Regarding claim 5, Richter teaches wherein the at least one alcohol of formula (III) is used in an amount of at least 2 mol-equivalents in regard to the compound of formula (II) [= in the electrolyte, the C1- to C6-mono alcohol, based on the 2-butene-1,4-diol derivative of the general formula (i), is employed in an equimolar amount or in an excess of up to 1:20] (page 3, [0044]).
Regarding claim 6, Richter teaches wherein the non-aqueous medium comprises at least one linear or branched C1-C10 alcohol (= the C1- to C6-monoalkyl alcohol preferably employed is methanol or isopropanol) [page 1, [0015]].
Regarding claim 7, Richter teaches wherein the non-aqueous medium comprises the mono alcohol of formula (III)
ROH (III),
wherein R is a linear or branched C1-C6 alkyl group (= the C1- to C6-monoalkyl alcohol preferably employed is methanol or isopropanol) [page 1, [0015]].
Regarding claim 9, Richter teaches wherein the cathode is not made from graphite (=
suitable cathode materials are, for example, iron, steel, stainless steel, nickel or noble metals such as platinum and also graphite or carbon materials, graphite being preferred. Cathodes having diamond surfaces are furthermore preferred) [page 3, [0055]].
Regarding claim 10, Richter teaches wherein the cathode is made from a material selected from the group consisting of metals and metal alloys (= suitable cathode materials are, for example, iron, steel, stainless steel, nickel or noble metals such as platinum and also graphite or carbon materials, graphite being preferred) [page 3, [0055]].
Regarding claim 11, Richter teaches wherein the anode is made from a material selected from the group consisting of noble metals, oxides, graphite, highly oriented pyrolytic graphite (HOPG), boron-doped diamond (BDD),dimensionally stable anodes (DSA) and glassy-carbon (= suitable anode materials are, for example, noble metals such as platinum or metal oxides such as ruthenium or chromium oxide or mixed oxides of the type RuOxTiOx. Graphite or
carbon electrodes are preferred. Anodes having diamond surfaces are furthermore preferred) [page 3, [0053]].
Regarding claim 12, Richter teaches which comprises applying a current density between 1-1000 mA/cm2 in the electrochemical reactor (= the current densities at which the process is carried out are in general 1 to 20 mA/cm2) [page 3, [0052]].
Regarding claim 13, Richter teaches wherein the process is carried out in the presence of at least one supporting electrolyte (= conductive salts) [page 3, [0046]].
Regarding claim 14, Richter teaches wherein the at least one supporting electrolyte is
not phosphoric acid and/or a salt thereof (= conductive salts which are comprised in the electrolysis solution are in general at least one compound selected from the group potassium, sodium, lithium, iron, alkali metal, alkaline earth metal and tetra(C1- to C6-alkyl)ammonium, preferably tri(C1- to C6-alkyl)methylammonium, salts. Suitable counterions are sulfate, hydrogensulfate, alkyl-sulfates, arylsulfates, halides, phosphates, carbonates, alkylphosphates, alkylcarbonates, nitrate, alcoholates, tetrafluoroborate or perchlorate) [page 3, [0046]].
Regarding claim 15, Richter teaches wherein the at least one electrolyte is chosen from the group consisting of HCl, H2SO4, Na2SO4, NaCl, sodium dodecyl sulfate, methyltributylammonium methylsulfate, triethylammonium bisulfate, tetrabutylammonium bisulfate, tetramethylammonium bisulfate, tetrabutylammonium acetate (NBu4OAc),
tetrabutylammonium sulfate, tetrabutylammonium hexafluorophosphate, tetrabutylammonium tetrafluoroborate, methanesulfonic acid, ammonium bisulfate,
tetrabutylphosphonium methanesulfonate, 1-methylimidazolium bisulfate,
tetrabutylammonium perchlorate and LiClO4 (= conductive salts which are comprised in the electrolysis solution are in general at least one compound selected from the group potassium, sodium, lithium, iron, alkali metal, alkaline earth metal and tetra(C1- to C6-alkyl)ammonium, preferably tri(C1- to C6-alkyl)methylammonium, salts. Suitable counterions are sulfate, hydrogensulfate, alkyl-sulfates, arylsulfates, halides, phosphates, carbonates, alkylphosphates, alkylcarbonates, nitrate, alcoholates, tetrafluoroborate or perchlorate) [page 3, [0046]].
Regarding claim 16, Richter teaches wherein the reaction is carried out batchwise or continuously (= preferably, it is carried out continuously using undivided flow cells) [page 3, [0051]].
II. Claim(s) 8 stands rejected under 35 U.S.C. 103 as being unpatentable over Richter et al. (US Patent Application Publication No. 2008/0110763 A1) in view of Pletcher et al. (“Flow Electrolysis Cells for the Synthetic Organic Chemistry Laboratory,” Chemical Reviews (2017 Sep 18), Vol. 118, No. 9, pp. 4573-4591) as applied to claims 1-7 and 9-16 above, and further in view of WO 2020/180838 (‘838).
Richter and Pletcher are as applied above and incorporated herein.
Regarding claim 8, the method of Richter differs from the instant invention because Richter does not disclose wherein the electrochemical reactor is a cuboid electrochemical reactor.
Richter teaches that preferably, it is carried out continuously using undivided flow cells (page 3, [0051]).
Pletcher teaches the laboratory arrangement for electrosynthesis using an undivided flow
cell with recycle of reactant solution is:
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(page 4577, Fig. 2(a)).
WO ‘838 teaches a flow-through electrochemical cell (= Title). Although the electrochemical cell 100 is illustrated with a cylindrical container 100, other container shapes, such as cuboid, cubic, or coin-shaped are possible (page 7, lines 19-20).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process described by Richter with wherein the process is carried out in a cuboid electrochemical reactor because a cuboid is an alternative shape for a cylindrical container of a flow-through electrochemical cell.
Known work in one field of endeavor may prompt variations of it for use in either the same field or a different field based on the function or property of the known material if the variations are predictable to one of ordinary skill in the art (MPEP § 2141 and § 2141.03).
The motivation to combine prior art references can arise from the expectation that the prior art elements will perform their expected functions to achieve their expected results when
combined for their commonly known purpose (MPEP § 2141 and § 2144.07).
Continued Response
Claim Objections
Claims 1, 5 and 9-11 are objected to because of the following informalities:
Claim 1
line 6, please insert the word -- of -- after the word “flow”.
Claim 5
line 2, please insert the word -- mono -- before the word “alcohol”.
This is an instance where the article should be added to ensure a consistency of the claim terminology.
Claim 9
lines 1-2, please amend “the cathode” to -- a cathode of the electrochemical reactor --.
This is an instance where the article should be amended to ensure a relationship of the claimed elements.
Claim 10
lines 1-2, please amend “the cathode” to -- a cathode of the electrochemical reactor --.
This is an instance where the article should be amended to ensure a relationship of the claimed elements.
line 2, please deleted the words “materials chosen”.
Claim 11
lines 1-2, , please amend “the anode” to -- an anode of the electrochemical reactor --.
This is an instance where the article should be amended to ensure a relationship of the claimed elements.
Appropriate correction is required.
Response to Arguments
Applicant’s arguments filed January 6, 2026 have been fully considered but they are not persuasive. The standing prior art rejections have been maintained for the following reasons:
• Applicant states that the Applicant is perplexed as to why the Examiner asserts, without hindsight knowledge of the present Applicant’s invention, the conclusion noted immediately above. Specifically, Richter uses undivided stacked plate cell and already achieves with such an arrangement quite good results. It is therefore not clear why the person ordinarily
skilled in the art should depart from the type of electrochemical reactor as suggested by Richter and instead seek to use a vertical flow electrochemical reactor.
In response, disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments (MPEP § 2123(II)).
Richter teaches that:
The process according to the invention can be carried out in all customary types of electrolysis cells. Preferably, it is carried out continuously using undivided flow cells. Very particularly suitable are bipolar-switched capillary gap cells or stacked plate cells, in which the electrodes are designed as plates and are arranged plane-parallel (cf. Ullmann's Encyclopedia of Industrial Chemistry, 1999 electronic release, Sixth Edition, VCH-Verlag Weinheim, Volume Electrochemistry, Chapter 3.5. special cell designs, and Chapter 5, Organic Electrochemistry, Subchapter 5.4.3.2 Cell Design). Such electrolysis cells are, for example, also described in DE-A-19533773 (page 3, [0051]).
Pletcher teaches organic electrosynthesis (page 4573, abstract).
Flow cells can lead to much improved performance. Electrolysis is participating in the
trend toward continuous flow synthesis, and this has led to a number of innovations in flow cell
design that make possible selective syntheses with high conversion of reactant to product with a single passage of the reactant solution through the cell (page 4573, abstract).
The laboratory arrangement for electrosynthesis using an undivided flow cell with recycle of reactant solution is:
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(page 4577, Fig. 2(a)).
Parallel plate cells have a number of advantages: (1) all points on the working electrode surface are equivalent with respect to the other electrode; (2) using simple polymer spacers, a constant narrow interelectrode gap is easily achieved; (3) uniform flow in the gap between the two electrodes can be realized; (4) a separator can be introduced without major changes to the cell design; and (5) scaling can readily be achieved by changing the area of the plate electrodes or using multiple cells in parallel (page 4577, right column, lines 18-26).
Laboratory parallel plate reactors maintain these advantages. Usually a single pair of electrodes is sufficient for the desired rate of conversion, and the cell may be divided or undivided. Figure 2 shows laboratory setups featuring cells, reservoirs, and pumps (page 4577, right column, lines 27-31).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the flow taught by Richter with wherein the flow is a vertical flow. The person with ordinary skill in the art would have been motivated to make this modification because Richter teaches that an undivided flow cell is a suitable selection for the electrolysis cells in [0051] where Pletcher teaches that the laboratory setup for electrosynthesis using a undivided flow cell with recycle of reactant solution utilizes a vertical flow between parallel plate electrodes as taught on page 4577, Fig. 2(a) and is a design that has a number of advantages: (1) all points on the working electrode surface are equivalent with respect to the other electrode; (2) using simple polymer spacers, a constant narrow interelectrode gap is easily achieved; (3) uniform flow in the gap between the two electrodes can be realized; (4) a separator can be introduced without major changes to the cell design; and (5) scaling can readily be achieved by changing the area of the plate electrodes or using multiple cells in parallel as taught on page 4577, right column, lines 18-31.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so
long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
• Applicant states that that the data in the originally filed specification evidence the advantages of vertical flow which is not at all suggested by the applied references of record. Specifically, comparing example 1 with example 12 of the application, the same electrolyte (methyltributylammonium methylsulfate), same starting material (2-butene-1,4-diol), same current density (3.4 Adm-2 = 34 mA/cm2), graphite/graphite electrodes, 20°/22°C, and methanol as ROH are employed. The differences therefore are mainly vertical flow rate and time of reaction. A comparison of the data shows that example 12 has significantly higher yield 71% vs 46% and
higher conversion 98 % vs 90%1) and higher Faraday efficiency 80% vs 55%.2
The reaction time in Richter is significantly longer than that employed in the present invention, e.g., Example 1 is 19 hours and Example 2 is 12 hours. In comparison, the Examples of the present invention achieved the following reaction times: Ex. 1: 90 mins, Ex.2: 190 mins, Ex. 3: 90 mins, Ex. 4 and 5: 60 mins. Ex. 6: 360 mins (=6 h) and Ex. 7-15: 450 mins (=7.5 h).
In response, a reference is not limited to the working examples, see In re Fracalossi, 215 USPQ 569 (CCPA 1982). Given that the choice of vertical flow rate and time of reaction results in the different behavior, the data presented is not commensurate with the far broader claims.
• Applicant states that the person ordinarily skilled in the art would expect faster development of hydrogen when the reaction time is reduced and, consequently, an expectation that lower yield and Faraday efficiency would result. As the data show, however, this expectation has not been observed with the presently claimed invention.
In response, Richter et al. in view of Pletcher et al. teaches the process of at least claims
1-7 and 9-16 as applied above. Similar processes can reasonably be expected to yield similar results. And because the fact that the Applicant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. Ex parte Obiaya, 227 USPQ 58,
60 (Bd. Pat. App. & Inter. 1985).
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to EDNA WONG whose telephone number is (571) 272-1349. The examiner can normally be reached Monday-Friday, 7:00 AM- 3:30 PM.
Examiner interviews are available via telephone, in-person, and video conferencing
using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Luan Van can be reached at (571) 272-8521. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/EDNA WONG/Primary Examiner, Art Unit 1795