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 .
DETAILED ACTION
1. This application is a 371 of PCT/CN2022/142367 12/27/2022; FOREIGN APPLICATIONS: CHINA 202210034548.2 01/13/2022.
Claims 2-21 are pending.
Response to Restriction Election
2. Applicant’s election of the species, disopropyl amine (secondary amine), the paraldehyde (the aldehyde), and the reducing agent (formic acid), in the reply filed on May 5, 2026 is acknowledged. The election was made without traverse. According to applicants’ representative claims 2-21 read on the elected species.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
3. Claims 2-21 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. An objective standard for determining compliance with the written description requirement is, "does the description clearly allow persons of ordinary skill in the art to recognize that he or she invented what is claimed." In re Gosteli, 872 F.2d 1008, 1012, 10 USPQ2d 1614, 1618 (Fed. Cir. 1989). Under Vas-Cath, Inc. v. Mahurkar, 935 F.2d 1555, 1563-64, 19 USPQ2d 1111, 1117 (Fed. Cir. 1991), to satisfy the written description requirement, an applicant must convey with reasonable clarity to those skilled in the art that, as of the filing date sought, he or she was in possession of the invention, and that the invention, in that context, is whatever is now claimed. The test for sufficiency of support in a parent application is whether the disclosure of the application relied upon "reasonably conveys to the artisan that the inventor had possession at that time of the later claimed subject matter." Ralston Purina Co. v. Far-Mar-Co., Inc., 772 F.2d 1570, 1575, 227 USPQ 177, 179 (Fed. Cir. 1985) (quoting In re Kaslow, 707 F.2d 1366, 1375, 217 USPQ 1089, 1096 (Fed. Cir. 1983)). Whenever the issue arises, the fundamental factual inquiry is whether the specification conveys with reasonable clarity to those skilled in the art that, as of the filing date sought, applicant was in possession of the invention as now claimed. See, e.g., Vas-Cath, Inc. v. Mahurkar, 935 F.2d 1555, 1563-64, 19 USPQ2d 1111, 1117 (Fed. Cir. 1991). See M.P.E.P. § 2163.02. In this case, the skilled artisan would not have reasonably concluded at the time of the invention that applicant was in possession of the entire invention as claimed.
Claim 2 is drawn to “protic ionic liquid”, which is not defined in the specification. They therefore seek to define compounds by particular functional requirements. The specification, however, does not provide any specific correlation between a particular structural property and the claimed function. The description is unclear for a variety of reasons. The term ionic liquid has a meaning in the art “Ionic liquids (ILs) are normally defined as compounds completely composed of ions with melting point below 100°C.”1 Protic ionic liquids (PILs) are not simply salts dissolved in a solvent. Instead, they are pure, neat salts that happen to be liquid at relatively low temperatures (usually below 100 °C).2 The distinction between PILs and protic salt solutions is important since the claims are limited to protic ionic liquids, yet are drawn to salt solutions in water. Protic ionic liquids (PILs) are pure, neat salts that happen to be liquid at relatively low temperatures (usually below 100 °C). When you dissolve table salt (NaCl) in water, water is the solvent and the salt is the solute. In contrast, a PIL is the liquid itself. It is 100% ions. See Greaves “Protic Ionic Liquids: Evolving Structure−Property Relationships and Expanding Applications.” Chem. Rev. 2015, 115, 11379−11448.
The specification describes a number of compounds as PILs, however this characterization is factually incorrect. The elected species, for instance, is formic acid-diisopropylamine salt is described as a protic ionic liquid on page 7 at paragraph [0052]. The sulfuric acid diisopropylamine salt and hydrochloric acid-diisopropylamine salt also are listed as protic ionic liquids at paragraph [0053] and [0054] respectively. However none of these compounds is actually an ionic liquid. These are known compounds with experimentally established melting points. Diisopropylammonium chloride has a m.p. of 210.5-213◦C,3 Diisopropylammonium sulfate has a m.p. of 111–116◦C,4 Diethylammonium dihydrogen phosphate has a m.p. 153–158◦C,3 Diethylammonium Tetrafluoroborate has a m.p. 172–176◦C,3 all of which are beyond 100oC, such that they are not PILs. Greaves “Protic Ionic Liquids: Properties and Applications” Chem. Rev. 2008, 108, 206-237 provides some examples with secondary amines in Figure 1 on page 208, which is a combination of both cation and anion properties. The Table 2 on page 210 ff. has a number of salts listed. For the elected species diisopropylamine, no anion gives an ionic liquid upon reaction with a protic acid. There are a few secondary amines listed however only a few of these are ionic liquids. di(ethylammonium) sulfate melts at ~200◦C, di(ethylammonium) HPO4 at 120oC, dimethylammonium H2PO4 at 117.3◦C, dimethylammonium CH3SO3 at 122.1oC, dibutylammonium BF4 at 212.8◦C. Of the acids listed in claim 16 various carboxylic acids (formic acid, acetic acid, propionic acid, oxalic acid, malonic acid), carbonic acid, HCl, sulfuric acid, phosphoric acid, and nitric acid only a few of these have the potential to form a PIL with a secondary amine. As best as can be determined no HCl, acetic acid, propionic acid, oxalic acid, malonic acid or carbonic acid salt with a secondary amine has ever been described as a PIL. Claim 1 is not limited and is drawn to any acid, and an open ended group of secondary amines which must give PILs. Predicting melting point based upon structure is not possible and must be determined experimentally. Melting point is a physical property dependent upon the structure of the compound in the crystal lattice. There is no way to predict the structure in the crystal lattice and therefore the melting point is likewise not predictable. See Katritzky “Perspective on the Relationship between Melting Points and Chemical Structure” Crystal Growth & Design, Vol. 1, No. 4, 2001 261-265, pages 261-262:
“Melting point is a fundamental physical property of organic compounds, which has found wide use in chemical identification, as a criterion of purity and for the calculation of other important physicochemical properties such as vapor pressure and aqueous solubility. Despite the enormous amount of available melting point data, few useful guidelines exist for understanding the relationship between the melting point of a compound and its chemical structure. It is frequently difficult to predict whether a compound will be a solid or a liquid until it is isolated.1….
Difficulties in the Correlation of the Melting Point.
The melting point is a difficult property to correlate because it is dependent upon the arrangement of the molecules in the crystal lattice as well as upon the strength of the pairwise group interactions. Available molecular descriptors do not satisfactorily describe the many-body crystal packing effects and intermolecular forces in condensed media.4 Melting point is determined by the strength of a crystal lattice, which, in turn, is controlled primarily by three factors: intermolecular forces, molecular symmetry, and the conformational degrees of freedom of a molecule.2 Most inorganic ionic compounds have high melting points, because the electrostatic forces holding the ions together are extremely strong. For organic compounds, the dominant intermolecular force affecting the melting point is intermolecular hydrogen bonding. Compounds with intramolecular hydrogen bonding normally exert less intermolecular attraction and, therefore, have a lower melting point than their intermolecularly hydrogen bonded analogues.2
Another factor that affects the melting point is the molecular motion in crystals. This can be quite significant and depends on the size and shape of the molecules, their orientation in the crystal, and on the temperature.5 The mechanisms of phase transitions in organic crystals are elusive. The ranges of stability for each phase are usually determined by the appearance of anomalies in the heat capacity temperature curves, but a phase transition can also be characterized by an abrupt change of optical, electrical, or mechanical properties of the sample.6…..
Similar problems arise in the prediction of solubility and vapor pressure of crystalline solids, as these can be regarded as a partitioning of the compound between its crystal lattice and the solvent or gas phase, respectively. If the forces holding the molecule in the crystal are strong, then the solubility and vapor pressure will be low. Conversely, the melting point will be high, as the melting point is a measure of the energy required to disrupt the crystal lattice.
Apart from the factors mentioned above, measurements of melting point are affected by the purity of a compound and experimental error.”
“In general, the melting point can be lowered through decreasing the packing efficiency of the ions. Numerous factors that influence the melting points of the PILs and AILs have been discussed in the literature.22,55,62,65,87,88 The key factors involve having sufficient steric hindrance to disrupt the packing efficiency and minimize the hydrogen bonding.” [Greaves page 218] Therefore looking at the structure of any hypothetical prophetic secondary amine base/acid pair and deciding if it has a melting point below 100oC is impossible. Applicants provide no guidance for identifying the compounds that meet the requirements and the claimed example compounds do not meet the accepted definition of PIL as discussed above, and as such the claims lack written description.
The fact pattern in this case is similar to that in University of Rochester v. G.D. Searle & Co., 68 USPQ2d 1424 (W.D.N.Y. 2003). In Rochester, there were no compounds known to have the required function. The key similarity between the cases, and the one relevant to this ground of rejection, is the fact that no method (other than trial-and-error) is provided for identifying compounds having the desired function. For this reason, the rejection due to lack of written description is proper.
Claim Rejections - 35 USC § 102
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 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.
4. Claim(s) 2-8, 11-18, 20-21 is/are rejected under 35 U.S.C. 102(a) (1) as being anticipated by Spialter, “Amines. III. Characterization of aliphatic tertiary amines.” Journal of Organic Chemistry, 1957, 22, 840-3. Spialter teaches the synthesis of the elected species by reaction of the secondary amine, diisopropyl amine, with formic acid, followed by formaldehyde as entry 3 in Table I on page 841, “The formalin solution was added to the amine dissolved in 88% formic acid. Sufficient heat (60 to 90°) was applied to maintain carbon dioxide evolution of 200-500 cc./min. In less than an hour gas evolution ceased.” At least the initial charge was at room temperature before heating. A standard atmosphere is .101325 MPa. In Table I of Spialter with the elected species, the molar ratio of amine to formic acid was 1:5, and 2.2 eq. of formaldehyde were used. Since the equilibrium would be complete upon addition of 5 eq. acid, the amount of “protic ionic liquid” is 1 eq. leaving 4 equivalents as reducing agent giving a reducing agent: “protic ionic liquid” of 4:1. The aldehyde:“protic ionic liquid” is 2.2:1 which falls within the range of claim 6 and 8. This is the compound of claim 11 where R1 and R2 are isopropyl and the aldehyde is of formula R3=H, and the protic ionic liquid in claim 12 is R1/R2 are isopropyl X is formate (C1 carboxyl), n is 1, x is 1.
5. Claim(s) 2-21 is/are rejected under 35 U.S.C. 102(a) (1) as being anticipated by Ouziel US 5,457,233. Ouizel teaches the claimed reaction, where R is H and R1 and R2 are isopropyl, the elected species is taught:
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Ouziel on col. 2 lines 35 ff teaches the same process and describes dropwise and multiple orders of addition:
The procedure comprises charging the aldehyde of formula (3) and the formic acid to the reactor in the presence of water and heating the reaction solution to the desired reaction temperature. The amine of formula (2) is then added dropwise, whereupon the pH of the reaction mixture rises slowly and is kept in the range from 3-7, preferably from 4-6, until completion of the reaction by addition of mineral acid. It is preferred to adjust the pH to a specific value within the claimed range by adding the amine and keeping this value until completion of the reaction by addition of mineral acid.
A variant of the process comprises charging the aldehyde of formula (3), the formic acid and sulfuric acid (H2SO4) or phosphoric acid to the reactor and adding the amine of formula (2) dropwise gradually. The reaction then commences at a strongly acid pH, which rises slowly in the course of the reaction and, upon conclusion of the reaction, reaches a value within the claimed range.
It is further possible to charge the amine of formula (2) and the formic acid to the reactor in the presence of water and to add the aldehyde of formula(3) dropwise. In this case, the mineral acid can be added at the start of, or during, the reaction..”
These are acids of claim 4 and combinations thereof. The reducing agent is formic acid. In the equimolar amounts and other amounts falling within claims 6 are taught, on column 2 lines 14-15, lines 24-26 “(14) The amine of formula (2), the aldehyde of formula (3) and the formic acid are preferably used in a molar ratio of 1/1/1… The amount of acid required is 0.3 to 2.0 molar equivalents and, preferably, 0.5 to 1 molar equivalent, of mineral acid per molar equivalent of amine of formula (2).” While claim 13, is not limited to paraformaldehyde, this was the elected aldehyde and is a known formaldehyde equivalent that is easier and safer to handle as a solid. In the examples Ouziel uses paraformaldehyde.
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.
6. Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Spialter, as applied to claims 2-8, 11-12, 14-18, 20-21 above further in view of Greco “Comprehensive Organic Chemistry Experiments for the Laboratory Classroom” 2017 translated from 2011 Portuguese language edition, edited by Carlos A M Afonso, RSC publishing, page 61 and Ouziel US 5,457,233. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: As discussed above in the example in Table I of Spialter with the elected species, the molar ratio of amine to formic acid was 1:5, and 2.2 eq. of formaldehyde were used. Since the equilibrium would be complete upon addition of 5 eq. acid, the amount of “protic ionic liquid” is 1 eq. leaving 4 equivalents as reducing agent giving a reducing agent: “protic ionic liquid” of 4:1. The aldehyde:“protic ionic liquid” is 2.2:1 which falls within the range of claim 6 and 8 and 18. Claim 19 give the ranges 0.4 to 1.2 for amine:acid, which in the prior art is .2 and 0.4 to 2.0 for aldehyde to “protic ionic liquid” respectively which excludes the prior art value of 2.2. Greco on page 61 explains: “When organic chemists carry out a reaction for the purpose of synthesizing a product, they often find that the percent yield of the product is lower than ideal. To improve the yield of desired product, a chemist will carry out the reaction under different reaction conditions (time, temperature, solvent, amounts of reagents). This process is referred to as optimizing the reaction.” One of ordinary skill would be motivated to optimize amounts of alkali metal fluoride increase the yield, as such optimizing the amount of reagents is routine optimization for the artisan and is not a patentable distinction over the known processes. In addition US 5,457,233 which teaches the same reaction suggests equimolar amounts, on column 2 lines 14-15, lines 24-26 “(14) The amine of formula (2), the aldehyde of formula (3) and the formic acid are preferably used in a molar ratio of 1/1/1… The amount of acid required is c. 0.3 to 2.0 molar equivalents and, preferably, 0.5 to 1 molar equivalent, of mineral acid per molar equivalent of amine of formula (2).” For these reasons the claims are obvious.
7. Claim(s) 9-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Spialter, as applied to claims 2-8, 11-18, 20-21 above further in view of Greco “Comprehensive Organic Chemistry Experiments for the Laboratory Classroom” 2017 translated from 2011 Portuguese language edition, edited by Carlos A M Afonso, RSC publishing, page 61 and Ouziel US 5,457,233. Spialter does not describe a dropwise addition or a reversed sequence of addition in claims 9-10. Dropwise addition of reagents is the standard practice for adding reagents since it allows for heat and gas evolution on a gradual basis. Ouziel on col. 2 lines 35 ff teaches the same process and describes dropwise and multiple orders of addition:
The procedure comprises charging the aldehyde of formula (3) and the formic acid to the reactor in the presence of water and heating the reaction solution to the desired reaction temperature. The amine of formula (2) is then added dropwise, whereupon the pH of the reaction mixture rises slowly and is kept in the range from 3-7, preferably from 4-6, until completion of the reaction by addition of mineral acid. It is preferred to adjust the pH to a specific value within the claimed range by adding the amine and keeping this value until completion of the reaction by addition of mineral acid.
A variant of the process comprises charging the aldehyde of formula (3), the formic acid and sulfuric acid (H2SO4) or phosphoric acid to the reactor and adding the amine of formula (2) dropwise gradually. The reaction then commences at a strongly acid pH, which rises slowly in the course of the reaction and, upon conclusion of the reaction, reaches a value within the claimed range.
It is further possible to charge the amine of formula (2) and the formic acid to the reactor in the presence of water and to add the aldehyde of formula(3) dropwise. In this case, the mineral acid can be added at the start of, or during, the reaction..”
Changing the sequence is prima facie obvious, MPEP 2144.04(IV)(C) “C. Changes in Sequence of Adding Ingredients Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959) (Prior art reference disclosing a process of making a laminated sheet wherein a base sheet is first coated with a metallic film and thereafter impregnated with a thermosetting material was held to render prima facie obvious claims directed to a process of making a laminated sheet by reversing the order of the prior art process steps.). See also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946) (selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results); In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930) (Selection of any order of mixing ingredients is prima facie obvious.).” In this case the order of addition was known to be modified. While claim 13, is not limited to paraformaldehyde, this was the elected aldehyde and is a known formaldehyde equivalent that is easier and safer to handle as a solid. In the examples Ouziel uses, paraformaldehyde.
8. Claim(s) 2-10, 14-21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chelucci “Synthesis of 1-substituted 2-[(2S)-2-pyrrolidinyl]pyridine from L-proline” Synthesis (1990), (12), 1121-2 in view of Ouziel US 5,457,233. The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
Determination of the scope and content of the prior art (MPEP 2141.01)
Chelucci on page 1122 column 2 first paragraph discloses the reductive amination of secondary amine free base, nornicotine, via Eschweiler-Clarke reaction with formaldehyde and formic acid (claim 4 as the C1 carboxylic acid and the reducing agent of claim 5) to yield nicotine, a tertiary amine.
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The amine:acid ratio is 0.196 which is about .2. The aldehyde : “protic ionic liquid” is 2.53. The reducing agent: “protic ionic liquid” is 4.1.
Ouziel on col. 2 lines 35 ff teaches the same process and describes dropwise and multiple orders of addition:
The procedure comprises charging the aldehyde of formula (3) and the formic acid to the reactor in the presence of water and heating the reaction solution to the desired reaction temperature. The amine of formula (2) is then added dropwise, whereupon the pH of the reaction mixture rises slowly and is kept in the range from 3-7, preferably from 4-6, until completion of the reaction by addition of mineral acid. It is preferred to adjust the pH to a specific value within the claimed range by adding the amine and keeping this value until completion of the reaction by addition of mineral acid.
A variant of the process comprises charging the aldehyde of formula (3), the formic acid and sulfuric acid (H2SO4) or phosphoric acid to the reactor and adding the amine of formula (2) dropwise gradually. The reaction then commences at a strongly acid pH, which rises slowly in the course of the reaction and, upon conclusion of the reaction, reaches a value within the claimed range.
It is further possible to charge the amine of formula (2) and the formic acid to the reactor in the presence of water and to add the aldehyde of formula(3) dropwise. In this case, the mineral acid can be added at the start of, or during, the reaction..”
Ouziel who teaches the same reaction suggests equimolar amounts, on column 2 lines 14-15, lines 24-26 “(14) The amine of formula (2), the aldehyde of formula (3) and the formic acid are preferably used in a molar ratio of 1/1/1… The amount of acid required is c. 0.3 to 2.0 molar equivalents and, preferably, 0.5 to 1 molar equivalent, of mineral acid per molar equivalent of amine of formula (2).”
Ascertainment of the difference between the prior art and the claims
The claim 1 only differs by the order of addition, the acid is added to the amine, which makes a salt and the then a reaction with the aldehyde and is done. Claim 19 has ranges of amine:acid ratio and aldehyde : “protic ionic liquid” that exclude the prior art range.
Finding of prima facie obviousness
(MPEP 2142-2143)
Changing the sequence of addition is prima facie obvious, MPEP 2144.04(IV)(C) “C. Changes in Sequence of Adding Ingredients Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959) (Prior art reference disclosing a process of making a laminated sheet wherein a base sheet is first coated with a metallic film and thereafter impregnated with a thermosetting material was held to render prima facie obvious claims directed to a process of making a laminated sheet by reversing the order of the prior art process steps.). See also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946) (selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results); In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930) (Selection of any order of mixing ingredients is prima facie obvious.).” In this case the order of addition was known to be modified. One of ordinary skill would be motivated to optimize amounts of alkali metal fluoride increase the yield, as such optimizing the amount of reagents is routine optimization for the artisan and is not a patentable distinction over the known processes.
Conclusion
9. Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID K O'DELL whose telephone number is (571)272-9071. The examiner can normally be reached on Monday - Friday 9:30 - 7:00 PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Clinton Brooks can be reached on 571-270-7682. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DAVID K O'DELL/Primary Examiner, Art Unit 1621
1 Lei “Introduction: Ionic Liquids” Chem. Rev. 2017, 117, 6633−6635.
2 MacFarlane “Ionic Liquids—Progress on the Fundamental Issues” Aust. J. Chem. 2007, 60, 3–5.
3 Dovell U.S. 3,336,386
4 Ganeshpure “Brønsted acidic ionic liquids derived from alkylamines as catalysts and mediums for Fischer esterification: Study of structure–activity relationship” Journal of Molecular Catalysis A: Chemical 279 (2008) 182–186.
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