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
Restriction to one of the following inventions is required under 35 U.S.C. 121:
I. Claims 1-18, drawn to a method of purifying a “precursor compound” by distillation, classified in C07C 7/04, G01G 19/00, G01G 33/00, and/or C01G 41/00.
II. Claims 19-20, drawn to a distillation system, classified in B01D1/22.
The inventions are independent or distinct, each from the other because:
Inventions I and II are related as process and apparatus for its practice. The inventions are distinct if it can be shown that either: (1) the process as claimed can be practiced by another and materially different apparatus or by hand, or (2) the apparatus as claimed can be used to practice another and materially different process. (MPEP § 806.05(e)). In this case 2, the apparatus as claimed can be used to practice a method of distilling mixture comprising something other than the precursor compound(s) as recited in the method claims.
Restriction for examination purposes as indicated is proper because all the inventions listed in this action are independent or distinct for the reasons given above and there would be a serious search and/or examination burden if restriction were not required because one or more of the following reasons apply:
a) The inventions have acquired a separate status in the art in view of their different classification.
b) The inventions have acquired a separate status in the art due to their recognized divergent subject matter.
c) The inventions require a different field of search (e.g., searching different classes/subclasses or electronic resources, or employing different search strategies or search queries).
Applicant is advised that the reply to this requirement to be complete must include (i) an election of an invention to be examined even though the requirement may be traversed (37 CFR 1.143) and (ii) identification of the claims encompassing the elected invention.
The election of an invention may be made with or without traverse. To reserve a right to petition, the election must be made with traverse. If the reply does not distinctly and specifically point out supposed errors in the restriction requirement, the election shall be treated as an election without traverse. Traversal must be presented at the time of election in order to be considered timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are added after the election, applicant must indicate which of these claims are readable upon the elected invention.
Should applicant traverse on the ground that the inventions are not patentably distinct, applicant should submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. In either instance, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention.
During a telephone conversation with Eric Nielson on 5/19/2026 a provisional election was made without traverse to prosecute the invention of Group I, claims 1-18. Affirmation of this election must be made by applicant in replying to this Office action. Claims 19 and 20 are withdrawn from further consideration by the examiner, 37 CFR 1.142(b), as being drawn to a non-elected invention.
Claim Interpretation
Claims 1-18 are drawn to a method of distilling a mixture (“crude product solution”) comprising a “precursor compound”.
The term “precursor” implies that a compound is capable of participating in a chemical reaction (e.g. as a reactant) which forms a different compound. Thus, the term “precursor” implies that a compound has a particular structure making it able to participate in a chemical reaction.
On the other hand, virtually every compound is capable of participating in some chemical reaction(s). Thus, absent some further definition of the term “precursor compound”, any compound could be fairly characterized as a “precursor compound”.
In reviewing Applicant’s specification, Examiner has not been able to find any clear, limiting definition of the term “precursor compound”. Furthermore, there is no indication that the term “precursor compound” has any accepted meaning in the art narrower than that described above. Accordingly, the term “precursor compound” is treated as referring to a compound which is capable of participating in a chemical reaction.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1, 2, 4, 5, 9, 12, 15, 16, and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Leese et al. (US 6,495,707), hereafter referred to as Leese.
With regard to claim 1: Leese teaches a method (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10), the method comprising:
Mixing a crude product solution with a first solvent (toluene) (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10). Note: The step of mixing here comprises a chemical reaction which forms trimethyl gallium (TMG).
Wherein the crude product solution comprises a precursor compound, i.e. the TMG, and multiple impurities, i.e. Me2AlCl, TMA, and trace partially alkylated gallium species (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
Wherein the boiling point of the first solvent is greater than a boiling point of the crude product mixture (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
Feeding a mixture of at least the crude product solution and the first solvent to an evaporator (reaction column) 2 (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
And collecting, from upper outlet pipe 12 of the evaporator 2, a distillate comprising the precursor compound (the TMG) (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
Leese does not explicitly teach that the purity of the precursor compound (the TMG) in the distillate is greater than 95% as determined by H NMR.
However, Leese’s disclosure indicates that it is desirable for the precursor compound in the distillate to be pure (Column 2 Lines 50-55, Column 3 Lines 34-36). It is well within the level of ordinary skill in the art to design a distillation column so as to yield a distillate having a desired purity. Indeed, Leese provides teachings/suggestions which show ways in which a pure product might be achieved (Column 2 Lines 50-55).
As for the purity being determined by H NMR, the method by which product purity is measured is not consequential, as the actual purity remains the same regardless of how it is determined.
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese by configuring the evaporator (reaction column) 2 to yield a distillate that comprises the precursor compound (TMG) at a purity greater than 95% as determined by H NMR, in order to obtain a pure distillate product as desired by Leese.
With regard to claim 2: As discussed in the rejection of claim 1 above, crude product solution comprises TMA, i.e. unreacted TMA (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10). This TMA can be alternatively characterized as a second solvent rather than an impurity.
It is understood that the precursor compound will be dissolved in (mixed with) the second solvent to some extent.
With regard to claim 4: The purity of the precursor compound in the crude product solution is less than 95% as evidenced by the 68% reaction yield (Column 4 Lines 8-10).
As for the purity being determined by H NMR, the method by which purity is measured is not consequential, as the actual purity remains the same regardless of how it is determined.
With regard to claim 5: Leese does not explicitly teach that the purity of the precursor compound in the crude product solution is 90-95% as determined by H NMR.
However, a process wherein the crude product solution has such a precursor compound purity is an obvious variation on the method of Leese.
With regard to claim 9: The first solvent (toluene) is inert with respect to the precursor compound (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
With regard to claim 12: The boiling point of the crude product solution is between 56 °C and 130 °C as evidenced by the operating temperature of the column boiler (i.e. a temperature of 130 °C) and that of the column top (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
With regard to claim 14: It is understood that the crude product solution of Leese will contain at least a small amount of unreacted gallium trichloride, i.e. gallium trichoride remaining following the reaction forming the precursor compound (TMG). Said unreacted gallium trichloride can be fairly characterized as a (dissolved) solid impurity.
With regard to claim 15: The at least one impurity contains Me2AlCl which is a dialkyl compound and a salt (Figure 1, Example 1, Column 4 Lines 4-8).
With regard to claim 16: Leese does not explicitly teach that the purity of the precursor compound (the TMG) in the distillate is at least 99%.
However, Leese disclosure indicates that it is desirable for the precursor compound in the distillate to be pure (Column 2 Lines 50-55, Column 3 Lines 34-36). It is well within the level of ordinary skill in the art to design a distillation column so as to yield a distillate having a desired purity. Indeed, Leese provides teachings/suggestions which show ways in which a pure product might be achieved (Column 2 Lines 50-55).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese by configuring the evaporator (reaction column) 2 to yield a distillate that comprises the precursor compound (TMG) at a purity of at least 99%, in order to obtain a pure distillate product as desired by Leese.
With regard to claim 18: Leese further comprises collecting a residue comprising the at least one impurity via overflow pipe 14 (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
Claim(s) 2, 5-7, 13, and 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Leese as applied to claim 1 above, and in further view of Lipiecki et al. (US 2009/0023940), hereafter referred to as Lipiecki.
With regard to claim 2: In Leese, the first solvent is toluene (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10). It is understood that the precursor compound (TMG) is dissolved in said first solvent (toluene).
Lipiecki teaches a similar method of producing organometallic compounds (abstract, paragraphs [0014], [0031]-[0033], [0065], and [0083]). Lipiecki’s disclosure indicates that there are many organic solvents which are suitable alternatives to toluene as a solvent (paragraph [0035]). On the subject of such organic solvents, Lipiecki teaches that “It will be appreciated that more than one organic solvent may be advantageously used,” (paragraph [0035]).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese in view of Lipiecki by using a mixture of the first solvent (toluene) with a second solvent (e.g. xylene or alkyl benzenes) which also dissolves the precursor compound (TMG) in order to obtain a predictably functional process which yields a pure precursor compound distillate.
With regard to claims 5-7: Leese is silent to the precursor compound comprising a tin, niobium, or tungsten compound.
However, Leese’s disclosure at least suggests that the method thereof can be applied to the production of other organometallic compounds (i.e. organometallic compounds other than TMG) (abstract, Column 1 lines 45-column 2 Line 40). Thus, there is an expectation that the method of Leese can be successfully applied to the production of organometallic compounds comprising tin, niobium, and tungsten, so as to yield such compounds as the precursor compound in the distillate Lipiecki teaches a similar method of producing organometallic compounds (abstract, paragraphs [0014], [0031]-[0033], [0065], and [0083]).
Lipiecki at least suggests that said method can be applied to the creation of organometallic compounds comprised tin (Sn) (paragraph [0033], see paragraph [0065] for additional context). Accordingly, the disclosure of Lipiecki would at least suggest that the method of Leese is applicable to the production of tin containing organometallic compounds.
Lipiecki at least suggests that said method can be applied to the production of organometallic compounds comprised of tungsten (W) (paragraph [0047], see paragraph [0065] for additional context). Accordingly, the disclosure of Lipiecki would at least suggest that the method of Leese is applicable to the production of tungsten containing organometallic compounds.
Lipiecki at least suggests that said method can be applied to the production of organometallic compounds comprised of Group II-Group VIII metals (paragraph [0047], see paragraph [0065] for additional context). Likewise, Lipiecki at least suggests that said method can be applied to the production of organometallic compounds comprised of tantalum (Ta) (paragraph [0047], see paragraph [0065] for additional context). Niobium (Nb) is understood to be a group V metal belonging to the same group as tantalum. Accordingly, the disclosure of Lipiecki would at least suggest that the method of Leese is applicable to the production of tungsten containing organometallic compounds.
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese in view of Lipiecki by applying the method of Leese to the production of organometallic compounds of tin, niobium, or tungsten, thereby obtaining a predictably successful method which produces a pure precursor compound distillate comprised of an organometallic compound of tin, niobium, or tungsten.
With regard to claims 10 and 11: Leese does not explicitly teach that the boiling point of the first solvent is 250 °C to 500 °C
Lipiecki teaches a similar method of producing organometallic compounds (abstract, paragraphs [0014], [0031]-[0033], [0065], and [0083]). Lipiecki’s disclosure indicates that C4-C20 alkyl benzenes are suitable alternatives to toluene as a solvent (paragraph [0035]). Indeed, it is understood that toluene itself is an alkyl benzene (a C1 alkyl benzene). Thus, a person having ordinary skill in the art would fully expect that higher alkyl benzenes would be suitable for use in place of toluene. It is well established that it would be obvious to one of ordinary skill to substitute one known prior art element for another (MPEP 2143).
It is understood that the group of C4-C20 alkyl benzenes includes substances which have boiling points between 250 °C and 500 °C. For example, n-nonylbenzene is understood to have a boiling point of somewhere in the range of roughly 270-282 °C.
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese in view of Lipiecki by using an alkyl benzene having a boiling point between 250 °C and 500 °C, e.g. n-nonylbenzene, rather than toluene as the first solvent, in order to obtain a predictably functional process which yields a pure precursor compound distillate.
In Leese, the boiling point of the crude product solution is between 56 °C and 130 °C as evidenced by the operating temperature of the column boiler (i.e. a temperature of 130 °C) and that of the column top (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10). Thus, in modified Leese, where the first solvent is an alkyl benzene having a boiling point between 250 °C and 500 °C, e.g. n-nonylbenzene, the first solvent has a first boiling point that is greater than a boiling point of the crude product solution.
With regard to claim 13: Leese does not explicitly teach that the first solvent comprises an isoparaffinic hydrocarbon fluid.
In Leese, the first solvent is toluene (Figure 1, Example 1, Column 3 Line 45-Column 4 Line 10).
Lipiecki teaches a similar method of producing organometallic compounds (abstract, paragraphs [0014], [0031]-[0033], [0065], and [0083]). Lipiecki’s disclosure indicates that squalane (an isoparaffinic hydrocarbon fluid) is a suitable alternative to toluene as a solvent (paragraph [0035]). It is well established that it would be obvious to one of ordinary skill to substitute one known prior art element for another (MPEP 2143).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese in view of Lipiecki by using squalane (an isoparaffinic hydrocarbon fluid) rather than toluene as the first solvent, in order to obtain a predictably functional process which yields a pure precursor compound distillate.
With regard to claim 17: Leese does not explicitly teach that the evaporator comprising at least one of a wiped film evaporator, a stirrer evaporator, a rising film evaporator, a circulation evaporator, a falling film evaporator, or any combination thereof.
Lipiecki teaches a similar method of producing organometallic compounds (abstract, paragraphs [0014], [0031]-[0033], [0065], and [0083]). Lipiecki’s disclosure indicates that at least wiped film evaporators are suitable alternatives to distillation columns for purifying organometallic compounds (paragraph [0085]). It is well established that it would be obvious to one of ordinary skill to substitute one known prior art element for another (MPEP 2143).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese in view of Lipiecki by carrying out the distillation following the mixing step in a wiped film evaporator in order to obtain a predictably functional process which yields a pure precursor compound distillate.
Claim(s) 1-3 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shenai-Khatkhate et al. (US 6,660,874), hereafter referred to as Shenai-Khatkhate.
With regard to claims 1 and 14: Shenai-Khatkhate teaches a method (Example 1, Column 8 Lines 30-51), the method comprising:
Mixing a crude product solution with a first solvent (xylene) (Example 1, Column 8 Lines 30-51). Note: The step of mixing here comprises a chemical reaction which forms trimethylstibine.
Wherein the crude product solution comprises a precursor compound (trimethylstibine) and at least one impurity, wherein the at least one impurity comprises at least a solid impurity, i.e. the solid contained within the “black slurry” (Example 1, Column 8 Lines 30-51).
Wherein the boiling point of the first solvent (xylene) is greater than a boiling point of the crude product solution (Example 1, Column 8 Lines 30-51).
Feeding a mixture of the crude product solution and the first solvent to an evaporator (distillation column) (Example 1, Column 8 Lines 30-51).
Collecting, from the evaporator, a distillate comprising the precursor compound (trimethylstibine) (Example 1, Column 8 Lines 30-51).
Shenai-Khatkhate does not explicitly teach that the purity of the precursor compound in the distillate is greater than 95% as determined by H NMR
However, Shenai-Khatkhate’s disclosure indicates that it is desirable for the precursor compound in the distillate to be pure (Column 2 Lines 45-47). It is well within the level of ordinary skill in the art to design a distillation column so as to yield a distillate having a desired purity.
As for the purity being determined by H NMR, the method by which product purity is measured is not consequential, as the actual purity remains the same regardless of how it is determined.
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Leese by configuring the evaporator to yield a distillate that comprises the precursor compound (trimethylstibine) at a purity greater than 95% as determined by H NMR, in order to obtain a pure distillate product as desired by Leese.
With regard to claims 3 and 4: In Shenai-Khatkhate, the first solvent is xylene (Example 1, Column 8 Lines 30-51). It is understood that the the precursor compound (trimethylstibine) is dissolved in said first solvent.
In Shenai-Khatkhate, the at least one impurity, being a solid, is not dissolved in the first solvent (Example 1, Column 8 Lines 30-51).
Shenai-Khatkhate does not explicitly teach that the crude product solution comprises a second solvent in which the precursor compound is dissolved but the at least one impurity is not.
However, Shenai-Khatkhate’s disclosure indicates that there are many organic solvents which are suitable alternatives to xylene as a solvent (Column 4 Lines 49-65). On the subject of such organic solvents, Shenai-Khatkhate teaches that “It will be appreciated that more than one organic solvent may be advantageously used,” (Column 4 Lines 59-61).
It would have been obvious to one of ordinary skill in the art before the effective filing date to modify Shenai-Khatkhate by using a mixture of the first solvent (xylene) with a second solvent (e.g. toluene or other alkyl benzenes) which also dissolves the precursor compound (trimethylstibine), but not the at least one impurity (the solid portion of the slurry), in order to obtain a predictably functional process which yields a pure precursor compound distillate.
Citation of Pertinent Art
The art made of record and not relied upon is considered pertinent to applicant's disclosure.
“An In-depth Technical Guide to the Physicochemical Properties of n-Nonylbenzene” by BenchChem Technical Support Team, shows that n-nonylbenzene is has a boiling point of somewhere in the range of roughly 270-282 °C.
US 6,867,315; US 6,956,127; US 7,045,451; US 7,166,734; and US 7,321,048 all disclose methods which could be relied upon in alternate 103 rejections of the claims.
US 7,282,119 teaches a method which bears at least some similarity to the method of Leese reference relied upon above.
US 7,659,414 is the granted patent corresponding to the Lipiecki PB Pub relied upon in the 103 rejections above.
Examiner Comments Concerning the Prior Art Relied Upon.
The 103 rejections set forth above rely on Lipiecki et al. (US 2009/0023940) as a secondary reference. However, it should be understood that Lipiecki could be relied upon as a primary reference in alternative 103 rejections of the claims.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JONATHAN "LUKE" PILCHER whose telephone number is (571)272-2691. The examiner can normally be reached Monday-Friday 9am-5pm.
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/JONATHAN LUKE PILCHER/ Examiner, Art Unit 1772
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