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 .
Status of the Claims
Claims 31-50 are pending and are rejected.
Priority
This application is a CON of 17/436,917, filed on 09/07/2021 (US 11,498,894), which is a 371 of PCT/US2020/020317, filed on 02/28/2020, which claims benefit of provisional application 62/815,993, filed on 03/08/2019.
The disclosure of the prior-filed applications, Application Nos. 17/436,917, PCT/US2020/020317 and 62/815,993, fails to provide adequate support or enablement in the manner provided by 35 U.S.C. 112(a) for one or more claims of this application.
Claims 31-50 require “contacting a beta propiolactone stream” with “an ammonia stream comprising an ammonia compound to form a beta-hydroxy amide stream” that “is substantially-free of beta-alanine compounds.” See, e.g., claim 31. The terms “a beta propiolactone”, “an ammonia compound” and “a beta-hydroxy amide” are broader than the narrow beta propiolactones, the ammonia compounds and the beta-hydroxy amides disclosed in the provisional application. Furthermore, the limitation “an ammonia compound” is not supported by any of the prior-filed applications nor by the instant specification.
Regarding the “beta propiolactone”, “ammonia compound” and “beta-hydroxy amide” limitations, the broadest disclosure in the provisional application is that of lactones of formula (1)
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(e.g., para. 129), ammonia compounds described as “an ammonia source configured to output ammonia” as mixed stream comprising beta lactone (R1=H) (para. 61), and beta-hydroxy amides of formula 2-I,
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(para. 91). Since the claims encompass subject matter that is broader than the previous disclosure, claims 31-50 are accorded an effective filing date of February 28, 2020.
Information Disclosure Statement
The information disclosure statements (IDSs) submitted on October 12, 2022 and May 8, 2023 are in compliance with the provisions of 37 CFR 1.97 and 37 CFR 1.98. Accordingly, the IDSs have been considered by the examiner and a signed copy is enclosed herewith.
Specification
The disclosure is objected to because it lacks antecedent basis for the claimed limitation “a beta propiolactone stream” and “an ammonia compound” in claim 31. The specification discloses a genus of beta lactones and a subgenus of formula 1 (e.g., para. 49), but does not disclose the claimed genus “a beta propiolactone stream.” In addition, the specification discloses “an ammonia source configured to output ammonia”, but does not mention “ammonia compounds” or provide examples. This objection may be overcome by adding the “beta propiolactone stream” limitation to the specification and by replacing “an ammonia compound” in the claim with “an ammonia source” or with “ammonia”. Note that claim 36 refers to “the ammonia compound” of claim 34.
Claim Objections
Claims 32 and 48 are objected to because of the following informalities:
(i) Claim 32, line 1, is missing the article “a” after “comprises”.
(ii) Claim 48, line 1, is missing the word “with” after “combined”.
Appropriate correction is required.
Claim Rejections - 35 USC § 112(b)
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 31-50 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.
The phrase “substantially free of beta-alanine compounds” in the last line of claim 31 is unclear. The specification does not define “substantially free”, but it does provide several examples by way of embodiments:
In some variations, the hydroxypropanamide stream comprises trace of additional products. In other variations, the hydroxypropanamide stream is substantially free of additional products. In one variation, "substantially free of additional products" refers to less than 1% (w/w), less than 5% (w/w), less than 10% (w/w), less than 15% (w/w) or less than 20% of additional products present in the stream. In other variations, "substantially free of additional products" refers to up to 20% (w/w) by weight of additional products present in the stream. In some variations, the hydroxypropanamide stream has a molar ratio of the compound of formula (2) to beta-alanine of between 100:1 to about 1:1, between 100:1 to about 10:1, or between 100:1 to about 50:1; or about 100:1: about 50:1; or about 10:1. In some embodiments, the hydroxypropanamide stream comprises trace beta-alanine. In other embodiments, the hydroxypropanamide stream is substantially free of beta-alanine. In one variation, "substantially free of beta-alanine" refers to less than 1 % (w/w), less than 5% (w/w), less than 10% (w/w), less than 15% (w/w) or less than 20% of beta-alanine present in the stream. (Paragraph 54.)
In the examples from Table 1, 8% w/w of beta-alanine is formed under aqueous conditions, while “trace” amounts are formed under anhydrous conditions. Page 50.
Based on the description and examples, although there are preferences, there is no clear limit to the maximum amount of beta-alanine permitted by the claims. Therefore, claim 31 and all dependent claims 32-50 are indefinite.
Claim 33 depends from claim 32 (which depends from claim 31) and requires complete conversion of the lactone compound to a “beta-hydroxy amide compound, a beta-alanine compound, and/or an oligomer.” However, claim 31 requires that “the beta-hydroxy amide stream is substantially free of beta-alanine compounds.” Since claim 33 encompasses complete conversion of the lactone to beta-alanine compounds and/or an oligomer, and these limitations cannot co-exist with the limitations of claim 31, claim 33 contradicts the requirements of claim 31. Consequently, claim 33 is unclear and indefinite, since a PHOSITA would not understand how to practice claim 33 given the constraints of claim 31.
Claim 35 depends from claim 33 and recites “the ether solvent”; however, neither claim 33 nor claim 35 previously mentions an ether solvent. Therefore, the limitation in claim 35 lacks antecedent basis in the claims.
Claim 50 depends from claim 31 and recites “the unsaturated amide”; however, neither claim 31 nor claim 50 previously mention an unsaturated amide. Therefore, the limitation in claim 50 lacks antecedent basis in the claims.
Claim Rejections - 35 USC § 112(d)
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 33 is rejected under 35 U.S.C. 112(d) as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 33 depends from claim 32 (which depends from claim 31) and requires complete conversion of the lactone compound to a “beta-hydroxy amide compound, a beta-alanine compound, and/or an oligomer.” However, claim 31 requires that “the beta-hydroxy amide stream is substantially free of beta-alanine compounds.” Since claim 33 encompasses complete conversion of the lactone to beta-alanine compounds and/or an oligomer, and these limitations cannot co-exist with the limitations of claim 31, claim 33 fails to further limit claim 32.
Claim Interpretation
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art.
The phrase “substantially free of beta-alanine compounds” in the last line of claim 31 is unclear. The specification does not define “substantially free”, but it does provide several examples by way of embodiments. See, e.g., paragraph 54 and Table 1. Based on the description and examples, although there are preferences, there is no clear limit to the maximum amount of beta-alanine permitted by the claims.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim 31 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Gresham et al. J. Am. Chem. Soc. 1951 as evidenced by National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 2365, Beta-Propiolactone. Retrieved July 23, 2026 from https://pubchem.ncbi.nlm.nih.gov/compound/Beta-Propiolactone (“PubChem”).
Gresham et al. combines β-propiolactone (I) with amines and reports competing ring-opening reactions to give either a β-hydroxy amide (II) or an amino acid (III). Gresham 3168 (left column).
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“The choice of solvent is important in determining where the lactone ring opens. With water as the solvent[,] ammonia and I give mostly hydracrylamide [].” Gresham 3168 (right column). See, e.g., Table Ia, which shows 90% yield of amide II (R2=H) and 0% of acid III obtained using ammonia in water, based on procedure B(c), wherein the lactone is added to the amine and the product is isolated by distillation.
Claim 31 requires “contacting a beta propiolactone stream” with an “ammonia stream” to form a “beta-hydroxy amide stream”. Gresham teaches anticipatory compounds, but is silent regarding their form as streams. However, since β-propiolactone is inherently a liquid (according to PubChem p. 11), ammonia is inherently a liquid (according to Official Notice), and the beta-hydroxy amide is also a liquid (as evidenced by its distillation), Gresham must have necessarily introduced the reagents and removed the product via streaming each liquid. Since the product stream contained 90% of the beta-hydroxy amide and 0% of the amino acid beta-alanine, Gresham’s process teaches all limitations of claim 31.
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 31-35, 38-41 and 49 are rejected under 35 U.S.C. 103 as being unpatentable over Allen et al. WO 2014/008232 in view of Kung et al. US 2,375,005 and Gresham et al. J. Am. Chem. Soc. 1951, as evidenced by National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 2365, Beta-Propiolactone. Retrieved July 23, 2026 from https://pubchem.ncbi.nlm.nih.gov/compound/Beta-Propiolactone (“PubChem”).
Allen teaches a continuous flow method for synthesizing acrylates and acrylamides by carbonylating an epoxide stream (with carbon monoxide and a carbonylation catalyst in an organic solvent) to form a beta-lactone stream. Ring-opening of the beta-lactone affords the desired product. See, e.g., Allen 10:16-24, 18:7-9, and 21:22-25.
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(Scheme 2)
Allen teaches recycling the carbonylation catalyst using solvent-assisted nanofiltration to separate the lactone from the catalyst, thereby forming streams of each. See, e.g., Allen 16:16-21. Two preferred solvents are suggested: THF and diethyl ether. Allen 17:6-10. “The permeate stream resulting from the nanofiltration step is carried onto an acrylate production step” (Allen 17:20-21). Allen is suggesting that a lactone stream in THF or diethyl ether is used in the subsequent ring-opening/dehydration reaction, for example, “in a continuous flow format” (Allen 18:14-15).
“In certain embodiments, the beta lactone product stream is reacted with a nucleophile of the formula Y-H to afford an acrylate having the formula I:
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. In certain embodiments, Y-H is an amine having the formula R11R12N-H, and the product is an acrylamide” (Allen 19:1-4).
“In some embodiments, the beta lactone in the permeate stream is allowed to polymerize and acrylic acid or derivatives thereof are obtained by decomposition of the polymer.” Allen 19:13-15.
Kung et al. teaches “beta lactones of monocarboxylic acids may be reacted with ammonia to prepare beta-hydroxy monocarboxylic acid amides which may then be converted into alpha-beta unsaturated carboxylic acid nitriles by dehydration.” Col. 1 ll.19-25. The nitriles “are extremely useful as polymerizable materials in the production of synthetic rubber, synthetic resins and the like.” Col. 1 ll.12-18.
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For example, hydracrylic acid lactone (a.k.a. beta-propiolactone, as evidenced by PubChem, p. 9) was heated in anhydrous liquid ammonia for 16 hours, the amide reaction product,
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, was distilled. The amide “was catalytically dehydrated in the vapor phase [] over alumina” to produce acrylonitrile. Col. 3 ll. 28 to col. 4 ll. 2. Though other catalysts can also be used, such as titanium oxide and silica gel. Col. 2:5-15.
Gresham et al. combines β-propiolactone (I) with amines and reports competing ring-opening reactions to give either a β-hydroxy amide (II) or an amino acid (III). Gresham 3168 (left column).
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“The choice of solvent is important in determining where the lactone ring opens. With water as the solvent[,] ammonia and I give mostly hydracrylamide [].” Gresham 3168 (right column). See, e.g., Table Ia, which shows 90% yield of amide II (R2=H) and 0% of acid III obtained using ammonia in water.
In view of the above, Allen teaches the claimed processes, comprising
(i) contacting an epoxide, a carbonylation catalyst and carbon monoxide to form a beta propiolactone (Allen 10:16-24 and Scheme 2), per claim 38, and
(ii) contacting the beta propiolactone in the form of a stream containing THF or diethyl ether (obtained from a nanofiltration step per Allen 17:6-10, 18:7-9, and 18:14-15) with an amine stream of the formula R11R12N-H to form an acrylamide that inherently proceeds through a beta-hydroxy amide stream (as evidenced by Kung), per claim 31.
Allen does not teach ammonia (required by the instant claims) as the amine of formula R11R12N-H, even though ammonia is encompassed by the amine genus; however, Kung teaches reacting liquid ammonia with beta-propiolactone to form a beta-hydroxy amide (Kung col. 3 ll. 28 to col. 4 ll. 2); therefore, since Kung produces the same product from the same starting material as Allen, a PHOSITA would have found it obvious to use ammonia as the amine in Allen’s reaction (wherein R11 and R12 are H).
Allen does not teach the claimed limitation “substantially free of beta-alanine compounds”; however, since Allen teaches further purifying the “acrylate product stream” and Gresham teaches beta-alanine is an undesired product, a PHOSITA would have found it obvious to optimize the reaction conditions and purify the acrylamide product in order to obtain a purer product substantially free of beta-alanine. See, e.g., Allen 21:1-5 and Gresham 3168 left column. Consequently, claims 31 and 38 would have been obvious in view of Allen, Kung and Gresham.
Regarding claim 32 requiring a carbonylation catalyst or a residue thereof in the lactone stream, a PHOSITA would have found it obvious to use such a lactone stream when nanofiltration does not provide complete removal of the catalyst after first filtration. Minimizing the amount of solvent used would have been expected to reduce the degree of separation of the lactone from the catalyst, and a PHOSITA would have been motivated to minimize the use of filtration solvents to reduce the environmental impact of solvent waste. Consequently, claim 32 would have been obvious.
Regarding claim 33 requiring complete conversion of the beta propiolactone to an oligomer, for example, Allen teaches an embodiment wherein “the beta lactone in the permeate stream is allowed to polymerize” (Allen 19:13-15). A PHOSITA wishing to oligomerize the beta propiolactone would have sought to achieve “complete conversion” to the oligomer by routine optimization.
Regarding claims 34-35, the beta propiolactone stream containing residual carbonylation catalyst would have also contained THF (claim 35) or diethyl ether according to Allen (17:6-10, 18:7-9, and 18:14-15).
Regarding claim 39, Allen’s conversion of the beta lactone product stream to the instant acrylamide (unsaturated amide) inherently proceeds through the claimed beta-hydroxy amide compound as evidenced by Kung. Allen uses ammonia as the dehydration agent, while Kung uses catalysts such as, alumina, titanium oxide or silica gel to further dehydrate the unsaturated amide to unsaturated nitriles. (Kung 2:5-13)
Regarding claim 40, neither Allen nor Kung teach using a combination of dehydration catalysts. However, since Kung provides a list of suitable catalysts (as discussed above regarding claim 39), a PHOSITA would have found it obvious to combine two catalysts in search of optimal conditions that increase the rate of dehydration. See, e.g., MPEP 2144.06 (“It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art.” In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) (citations omitted).)
Regarding claim 41, neither Allen nor Kung teach using a combination of dehydration catalysts TiO2 and SiO2, as discussed above regarding claim 40; however, a PHOSITA would have found it obvious to combine TiO2 and SiO2 taught by Kung in search of optimal conditions that increase the rate of dehydration. See, e.g., MPEP 2144.06. Since Kung discloses only 11 catalysts, which include TiO2 and SiO2, a PHOSITA would have found it obvious to combine TiO2 and SiO2 given the finite number of predictable dehydration catalysts.
Regarding claim 49, Allen does not teach polymerizing acrylonitriles; however, Kung teaches that the beta-hydroxy amides can be dehydrated to acrylonitriles. See, e.g., equations 1 and 2 (col. 1).
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A PHOSITA would have been motivated to polymerize the acrylonitriles, because Kung teaches they “are extremely useful as polymerizable materials in the production of synthetic rubber, synthetic resins and the like.” Col. 1 ll.12-18. Therefore, the claimed process would have been obvious.
Claim 50 is rejected under 35 U.S.C. 103 as being unpatentable over Allen et al. in view of Kung et al. and Gresham et al. as evidenced by “PubChem” as applied to claims 31-35, 38-41 and 49 above, in further view of Harris et al. WO2013/185009 A1.
As discussed above regarding claim 31, Allen teaches the claimed process, comprising
contacting the beta propiolactone in the form of a stream containing THF or diethyl ether (obtained from a nanofiltration step per Allen 17:6-10, 18:7-9, and 18:14-15) with an amine stream of the formula R11R12N-H to form an acrylamide that inherently proceeds through a beta-hydroxy amide stream (as evidenced by Kung), per claim 31.
Allen does not teach ammonia (required by the instant claims) as the amine of formula R11R12N-H, even though ammonia is encompassed by the amine genus; however, Kung teaches reacting liquid ammonia with beta-propiolactone to form a beta-hydroxy amide (Kung col. 3 ll. 28 to col. 4 ll. 2); therefore, since Kung produces the same product from the same starting material as Allen, a PHOSITA would have found it obvious to use ammonia as the amine in Allen’s reaction (wherein R11 and R12 are H).
Allen does not teach the claimed limitation “substantially free of beta-alanine compounds”; however, since Allen teaches further purifying the “acrylate product stream” and Gresham teaches beta-alanine is an undesired product, a PHOSITA would have found it obvious to optimize the reaction conditions and to purify the acrylamide product in order to obtain a purer product free of beta-alanine. See, e.g., Allen 21:1-5 and Gresham 3168 left column. Consequently, claim 31 would have been obvious in view of Allen, Kung and Gresham.
Regarding instant claim 50, which requires polymerizing an unsaturated amide to form a polymer, Harris teaches acrylamides “readily combine” with acrylic acid and esters thereof, “forming homopolymers or copolymers which are used in the manufacture of various plastics,” etc. (Harris para. 104). Therefore, a PHOSITA would have been motivated to polymerize the acrylamides taught by Allen and Kung, because Harris teaches that acrylic acid copolymers of acrylamides are useful for making plastics. Consequently, the claimed process would have been obvious.
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.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
(1 of 3) Claims 31-35, 38-44 and 49-50 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-20 of U.S. Patent No. 11,498,894 in view of Allen et al. WO 2014/008232, Kung et al. US 2,375,005 and Gresham et al. J. Am. Chem. Soc. 1951, as evidenced by National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 2365, Beta-Propiolactone. Retrieved July 23, 2026 from https://pubchem.ncbi.nlm.nih.gov/compound/Beta-Propiolactone (“PubChem”).
Although the claims at issue are not identical, they are not patentably distinct from each other because the ‘894 patent teaches an obvious variation of the claimed process in view of Allen, Kung and Gresham.
Claims 3-6 and 10-14 of the ‘894 patent disclose “combining a beta lactone with ammonia” to prepare a beta-hydroxy amide stream. According to claims 1-2, 7-9 and 15-20, the beta hydroxy amide stream is then combined with a dehydration agent to produce an unsaturated amide or unsaturated nitrile product stream. This process is substantially similar to instant claims 31 and 39, the difference being that claim 31 requires the reagents in streams and the product to be substantially free of beta alanine. These differences would have been obvious to a PHOSITA in view of Allen, Kung and Gresham, as previously discussed in the obviousness rejection of claims 31 and 39.
The ‘894 patent does not teach the beta lactone stream comprising a carbonylation catalyst, as required by instant claim 32; however, this limitation would have been obvious in view of Allen’s nanofiltration and continuous flow processes discussed previously in the obviousness rejection of claim 32.
The ‘894 patent is silent regarding the degree of conversion of the lactone to an oligomer, whereas instant claim 33 requires complete conversion thereof; however, this limitation would have been obvious in view of Allen’s teaching that “the beta lactone in the permeate stream is allowed to polymerize” (Allen 19:13-15). A PHOSITA wishing to oligomerize the beta propiolactone would have sought to achieve “complete conversion” to the oligomer by routine optimization.
The ‘894 patent does not teach using an ether solvent, such as THF, as required by instant claims 34 and 35 for the lactone ring opening; however, this limitation would have been obvious in view of Allen as previously discussed in the obviousness rejection of claims 34 and 35. See, e.g., Allen 17:6-10, 18:7-9, and 18:14-15.
Claim 6 of the ‘894 patent discloses a process comprising contacting an epoxide with carbon monoxide in the presence of a carbonylation catalyst, which process is required by instant claim 38.
Claims 16-18 of the ‘894 patent teach the process limitations of instant claims 40-44.
Claim 19 of the ‘894 patent teach the process limitations of instant claims 49 and 50.
(2 of 3) Claims 31-35, 38-41 and 49-50 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-35 of U.S. Patent No. 11,718,714 in view of Allen et al. WO 2014/008232, Kung et al. US 2,375,005 and Gresham et al. J. Am. Chem. Soc. 1951, as evidenced by National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 2365, Beta-Propiolactone. Retrieved July 23, 2026 from https://pubchem.ncbi.nlm.nih.gov/compound/Beta-Propiolactone (“PubChem”).
Although the claims at issue are not identical, they are not patentably distinct from each other because the ‘714 patent discloses synthetic methods that are obvious variants of the claimed methods.
Claims 1-35 (esp. claims 1 and 3) teach contacting an alkylene oxide and carbon monoxide to synthesize a lactone (comparable to instant claim 38), converting the lactone to a beta-hydroxy amide using aq. ammonia (comparable to instant claim 31), and polymerizing the amide to form a polyamide (comparable to instant claim 50). Instant claim 31 has several obvious differences: (i) using the lactone, the amine (in this case, ammonia) and the amide product in their stream forms, and (ii) the amide product is substantially free of beta-alanine compounds. As discussed above in the obviousness rejection of claim 31 over Allen, Kung and Gresham, using said streams and producing the amide substantially free of beta-alanines would have been obvious to a PHOSITA.
The ‘714 patent does not teach the limitation of instant claims 32-35, 39-41 and 49; however, these limitations would have been obvious in view of Allen, Kung and Gresham as discussed above in the obviousness rejection of said claims.
(3 of 3) Claims 31-35, 38-41 and 49-50 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-20 of U.S. Patent No. 12,209,165 in view of Allen et al. WO 2014/008232, Kung et al. US 2,375,005 and Gresham et al. J. Am. Chem. Soc. 1951, as evidenced by National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 2365, Beta-Propiolactone. Retrieved July 23, 2026 from https://pubchem.ncbi.nlm.nih.gov/compound/Beta-Propiolactone (“PubChem”).
Although the claims at issue are not identical, they are not patentably distinct from each other because the ‘165 patent discloses synthetic methods that are obvious variants of the claimed methods.
Claims 1-20 (esp. claims 1 and 4) teach contacting an alkylene oxide and carbon monoxide to synthesize a beta lactone (comparable to instant claim 38), converting the lactone to a beta-hydroxy amide using ammonia (comparable to instant claim 31), and polymerizing the amide to form a polyamide (comparable to instant claim 50). Instant claim 31 has several obvious differences: (i) using the lactone, the ammonia and the amide product in their stream forms, and (ii) the amide product is substantially free of beta-alanine compounds. As discussed above in the obviousness rejection of claim 31 over Allen, Kung and Gresham, using said streams and producing the amide substantially free of beta-alanines would have been obvious to a PHOSITA.
The ‘165 patent does not teach the limitation of instant claims 32-35, 39-41 and 49; however, these limitations would have been obvious in view of Allen, Kung and Gresham as discussed above in the obviousness rejection of said claims.
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AMANDA L AGUIRRE whose telephone number is (571)272-5592. The examiner can normally be reached 10 am-6 pm MST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, JEFFREY H. MURRAY can be reached on 571-272-9023. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/AMANDA L. AGUIRRE/Primary Examiner, Art Unit 1626
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