Symrise AG

Patent Trials and Appeals Board

Jun 24, 2020

15575076 - (D) (P.T.A.B. Jun. 24, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/575,076 11/17/2017 Erich Dilk 1507-211 9220
28249 7590 06/24/2020
DILWORTH & BARRESE, LLP
Dilworth & Barrese, LLP
1000 WOODBURY ROAD
SUITE 405
WOODBURY, NY 11797
EXAMINER
KEYS, ROSALYND ANN
ART UNIT PAPER NUMBER
1699
NOTIFICATION DATE DELIVERY MODE
06/24/2020 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
usptomail@dilworthbarrese.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte ERICH DILK, DETLEF GEISEL, and STEFAN LAMBRECHT
__________

Appeal 2019-006459
Application1 15/575,076
Technology Center 1600
__________

Before RICHARD M. LEBOVITZ, ULRIKE W. JENKS, and
RACHEL H. TOWNSEND, Administrative Patent Judges.

TOWNSEND, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a process
for the oxidation of limonene, which have been rejected as obvious. We
have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
STATEMENT OF THE CASE
“The aromatic main constituents of citrus essential oils are
monoterpenes, sesquiterpenes and the oxygen-containing derivatives
thereof.” (Spec. ¶ 2.) “The sensory properties of citrus aromas mainly

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies the real party in interest as Symrise AG.
(Appeal Br. 2.)
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depend on the content of oxygen-containing terpene derivatives, alcohols,
aldehydes, esters and ketones.” (Id.) Limonene is a monoterpene that is in
high concentration in citrus oil and “negatively influence[s] the sensory
properties of citrus aromas.” (Id.) “[I]t is generally known . . . [to be] used
as an educt for the production of particular perfumes, aromas or flavours,
and also of intermediate compounds thereof.” (Id. ¶ 6.) Appellant’s
invention “relates to a process for the production of oxidized derivatives of
limonene.” (Id. ¶ 1.)
Claims 1–21 are on appeal. Claim 1 is representative and reads as
follows:
1. A process for the oxidation of limonene, comprising the
reaction of limonene with hydrogen peroxide in the presence of
a catalyst containing atoms and/or ions of at least one metal
selected from the group consisting of molybdenum, tungsten,
scandium, titanium, lanthanum, zirconium, praseodymium,
neodymium, samarium, europium, terbium, dysprosium, erbium
or ytterbium and mixtures thereof, wherein the molecular
weight of the catalyst is less than 2,000 g/mol and the reaction
is performed at a pH value of more than 8.0.
(Appeal Br. 27.)

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The prior art relied upon by the Examiner is:
Name Reference Date
Emsenhuber et al. US2004/0220416 A1 Nov. 4, 2004
Bain et al. US 3,014,047 Dec. 19, 1961
V. Nardello et al., Olefin oxidation by the system H2O2/MoO42-:
competition between epoxidation and peroxidation, 117 J. Molec.
Catalysis A: Chemical, 439–47 (1997) (Nardello 1)
V. Nardello, Singlet oxygen generation from H2O2/MoO42-: peroxidation
of hydrophobic substrates in pure organic solvents, 43 Tetrahedron
Letters, 8731–34, (2002) (Nardello 2)

The following grounds of rejection by the Examiner are before us on
review:
Claims 1–11 and 19–21 under 35 U.S.C. § 103 as unpatentable over
Emsenhuber, Nardello 1, and Nardello 2.
Claims 12–18 under 35 U.S.C. § 103 as unpatentable over
Emsenhuber and Bain.
DISCUSSION
Obviousness: Claims 1–11 and 19–21
The Examiner finds that Emsenhuber teaches a process for oxidation
of organic substrates, including olefins such as tiglic acid and limonene, with
1O2 via catalytic decomposition of H2O2 to give water and 1O2. (Final
Action 4; Ans. 9.) The Examiner notes that Emsenhuber teaches a number
of catalysts including those based on all of the metals identified in claim 1
and teaches the use of a catalyst having a molecular weight of less than
2,000 g/mol as claimed. (Id.) The Examiner further finds that Emsenhuber
teaches the pH of the reaction mixture can be between 0 and 14, and
preferably between 4 and 14, and the particular pH depends on the chosen
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substrate and catalyst. (Id.) The Examiner notes that Emsenhuber provides
a specific example of using Na2MoO4 catalyst in a process in which the pH
is about 10 which meets the claim limitation of a pH value of more than 8.0.
(Id. at 5.)
The Examiner recognizes that Emsenhuber does not specifically
identify carrying out the reaction of limonene at a pH of more than 8, or
more than 9. (Id.) However, the Examiner concludes that doing so would
have been obvious to one of ordinary skill in the art in light of Emsenhuber
and Nardello 1. (Id. at 5–6; Ans. 8–12.)
The Examiner finds that Nardello 1 teaches quantitatively creating
singlet oxygen, 1O2, by catalysis of hydrogen peroxide in alkaline media, pH
of 9–12, in the presence of molybdate ions. (Final Action 5–6.) The
Examiner further finds that Nardello 1 teaches “the pH of the reaction
effects selectivity to the epoxidized or peroxidized product.” (Id. at 5; Ans.
8.) Thus, explains the Examiner, Nardello 1 “demonstrate[s] that pH is a
result effective variable.” (Ans. 8.)
The Examiner finds further that the reaction disclosed in Nardello 1
“is analogous to the reaction disclosed by Emsenhuber et al. [in] that it
involves oxidation of an organic substrate, in particular an olefin, by means
of 1O2 that has been generated by H2O2.” (Ans. 9.) Consequently, the
Examiner finds that it would have been obvious to one of ordinary skill in
the art to conduct the Emsenhuber process with limonene at pH of 9 or
above where “one desires to obtain the peroxide compounds” rather than
epoxide compounds of limonene. (Id.)
The Examiner relies on the teachings of Nardello 2 to address the
limitation of claims 19 and 20 that the oxidation reaction be complete in less
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than 24 hours. (Final Action 6.) In particular, the Examiner finds that
Nardello 2 teaches the rate of molybdate catalyzed H2O2 disproportionation
to generate 1O2 “is strongly influenced by temperature.” (Id.) The Examiner
finds, for example, Nardello 2 teaches that decomposition of 0.5 M H2O2 by
0.1 M Li2MoO4 at 25 ºC takes more than 12 hours but that the reaction time
is decreased to only 28 min when carried out at 40 ºC. (Id.) The Examiner
further finds that “although limonene is not the substrate discussed or
employed in Nardello et al. 2, the skilled artisan would reasonably expect
the teachings of Nardello et al. 2 to be pertinent to limonene, since Nardello
et al. 2 uses similar substrates as Emsenhuber et al.” (Ans. 21.)
The Examiner notes further that “temperature is not the only result-
effective variable in the reaction of Nardello et al. 2. However, Nardello et
al. 2 show that temperature is one of the variables that [a]ffects the reaction
time and in particular the temperature is inversely proportional to the
reaction time.” (Ans. 15–16.) Consequently, the Examiner concludes that
one of ordinary skill in the art would have reasonably expected “that when
using a catalyst having the molybdate ions in the process of Emsenhuber et
al. that the reaction time can be completed in less than 24 hours by
modifying the temperature in the manner taught by Nardello et al. 2.” (Final
Action 6.)
We agree with the Examiner’s factual findings and conclusion of
obviousness regarding claim 1. As the Examiner explained, Emsenhuber
teaches limonene is one of the preferred olefinic organic substrates that can
be oxidized with 1O2, obtained from the chemical catalysis of H2O2 in the
presence of a molybdenum based catalyst at a pH between 4 and 14.
(Emsenhuber ¶¶ 14, 17, 20–29, 72–75.) And, Emsenhuber teaches a specific
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example of oxidizing a “test solution” of sodium tiglate, (E)-2-
methylcrotonic acid, at pH of about 10, with H2O2 in the presence of
Na2MoO4. (Id. ¶¶73–74 (Example 4).) Furthermore, as the Examiner points
out (Ans. 11–12), Emsenhuber itself discloses that “it may be advantageous,
for better activation of the catalyst, if customary basic and acidic additives
are added to the reaction mixture,” (Emsenhuber ¶ 25), and that these
additives would necessarily adjust the pH of the reaction mixture. In other
words, Emsenhuber teaches that pH is a result effective variable. “[T]he
discovery of an optimum value of a variable in a known process is normally
obvious.” In re Antonie, 559 F.2d 618, 620 (CCPA 1977).
However, even if it were not deemed obvious to carry out the
oxidation of limonene as described in Emsenhuber at an alkaline pH of 9 or
higher based on Emsenhuber alone, as the Examiner further explained,
Nardello 1 demonstrates that the pH of the catalytic system employing H2O2
and MoO4-2 is result effective where alkaline pH in the range of 9–12
promotes peroxidation over epoxidation of olefins. (See, e.g., Nardello 1
439, 444–46.) Tiglic acid was chosen as a model olefin in the analysis
because it is water soluble and known to react both by epoxidation and by
peroxidation with 1O2. (Id. at 443–44.)
In light of the foregoing, we agree with the Examiner that Nardello 1
demonstrates pH is a result effective variable known in the art in the reaction
process taught by Emsenhuber for olefinic substrates (Ans. 8), and that one
of ordinary skill in the art would have found it obvious to carry out the
Emsenhuber reaction at alkaline pH of 9 or more in order to preferentially
achieve peroxidation rather than epoxidation (Ans. 9).
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We do not find persuasive Appellant’s argument that because
Emsenhuber provides an “expansive description of the ‘organic substrate’”
that there is “no guidance to one skilled in the art as to which pH would
function for the specifically chosen substrate of limonene” (Appeal Br. 12–
13). Nor do we find persuasive Appellant’s argument that because Nardello
1 only discloses oxidation of tiglic acid, one would not have been able to
determine that limonene would benefit by the same pH range (Appeal Br.
15–16). One of ordinary skill in the art would have had a reasonable
expectation of being able to oxidize each one of the specifically identified
olefins (which includes tiglic acid, as well as limonene, and salts thereof
(Emsenhuber ¶¶ 17–18)) of Emsenhuber with singlet oxygen made through
the catalytic decomposition of H2O2 at a pH of between 4 and 14 because
Emsenhuber describes each of them as “[e]xamples of particularly suitable
[olefin] substrates” for use in the described oxidation reaction. And,
Nardello 1 provides a specific reason to use an alkaline pH of greater than 9,
i.e., to achieve peroxidation of an olefin rather than epoxidation. Sinclair &
Carroll Co. v. Interchemical Corp., 325 U.S. 327, 335 (1945) (“[r]eading a
list and selecting a known compound to meet known requirements is no
more ingenious than selecting the last piece to put into the last opening in a
jig-saw puzzle. It is not invention.”); see also Merck & Co. Inc. v. Biocraft
Laboratories, Inc., 874 F.2d 804, 807 (Fed. Cir. 1989). “Only a reasonable
expectation of success, not absolute predictability, is necessary for a
conclusion of obviousness.” In re Longi, 759 F.2d 887, 897 (Fed. Cir. 1985)
(“The fact that some titanium compounds function more effectively, and that
the exact magnitude of the increased catalytic activity might not be
predictable, does not preclude a conclusion of obviousness.”).
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Although Nardello 1 chose tiglic acid as the olefin to study, Nardello
1 concludes more generally that in substrates that are subject to epoxidation
and peroxidation in the “double reactivity of the system hydrogen
peroxide/molybdate ions,” alkaline medium the formation of the
intermediate MoO(O2)32- allows one to obtain the hydroperoxide via the
generation of singlet oxygen, whereas in an acidic medium the formation of
Mo2O3(O2)42- leads to the epoxide. (Nardello 1 446.) Limonene was an
olefin well known to be a substrate that undergoes both epoxidation and
peroxidation. (See, e.g., Bain 3:30–36.) For the foregoing reason, we also
do not find persuasive of non-obviousness, the fact that Example 4 of
Emsenhuber discloses carrying out the reaction at pH 10 with sodium tiglate
and not limonene (Appeal Br. 13).2
We also agree with the Examiner that Emsenhuber does not teach
away from Nardello 1, as argued by Appellant (Appeal Br. 14–15). One of

2 We also do not find persuasive, Appellant’s argument that one of ordinary
skill in the art would not combine the teachings of Nardello 1 with
Emsenhumber because Nardello 1 used water as the solvent which is in
“stark contrase to Emsenhumber.” (Appeal Br. 15.) As the Examiner finds
Emsenhuber teaches “[t]he reaction is conducted in a water-miscible organic
solvent or in water or in a mixture of water and water-miscible solvent,
which includes C1-C8 alcohols and amides.” (Final Action at 4–5;
Emsenhumber ¶ 20 (“The oxidation according to the invention takes
place in a water-miscible organic solvent or in water or in a
mixture of water and a water-miscible organic solvent.” (Emphasis added).)
Moreover, as the Examiner explains, which Appellant does not respond to,
The presence of water is not taught to be avoided by
Emsenhuber et al., instead Emsenhuber et al. provides a means
to overcome the presence of water by removing the water with
a membrane.
(Ans. 17.)
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ordinary skill in the art would not have been discouraged from carrying out
the 1O2 oxidation at an alkaline pH as described in Nardello 1 by the fact that
Emsenhuber teaches that single O2 generated is lost as a result of quenching
by water molecules. As the Examiner, explains “Emsenhuber et al. disclose
an improved way to carry out the 1O2 oxidation of Nardello et al. 1 by using
membranes to remove the water contained in the reaction mixture (see
paragraphs 0009-0012 of Emsenhuber et al.).” (Ans. 12.) Furthermore, as
the Examiner explained, Emsenhuber teaches that water is a suitable reaction
solvent for the described oxidation process with singlet oxygen catalytically
generated from H2O2. (Id.)
We also do not find persuasive Appellant’s argument that Nardello 1
describes that choosing the appropriate pH is complex and difficult to
forecast (Appeal Br. 15). As the Examiner explains (Ans. 13–14), Nardello
1 states that “the kinetics of the reactions under study are very complex and
it is difficult to forecast exactly th[e] pH value [for which both the
tetraperoxodimolybdate and triperoxomolybdate oxidizing intermediates are
in equal amounts] only by considering the equilibrium constants.” (Nardello
1 446.) It does not say that identifying a pH by routine experimentation to
achieve peroxidation of an olefin is difficult to forecast or complex.
Appellant does not separately argue claims 5, 7, 8, or 21 and therefore
these claims fall with claim 1. 37 C.F.R. § 41.37(c)(1)(iv).
Regarding the requirement in claims 19 and 20 that the reaction is
complete in less than 24 hours, we agree with the Examiner that such would
have been obvious in light of the combination of Emsenhuber, Nardello 1,
and Nardello 2. Appellant’s argument against this part of the rejection is
that there is no illustration in Nardello 2 with data that “with the use of
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ethanol solvent an increase in the temperature would influence the reaction
rate” and that “[o]ther factors also can play a dramatic role” in reaction time.
(Appeal Br. 16.) We do not find these arguments persuasive. First, the
Examiner provides where in Nardello 2 data is provided that exemplifies the
inverse relationship of temperature to reaction time (Ans. 15 (quoting from
Nardello 2 8733)), which Appellant does not respond to. Furthermore, we
agree with the Examiner (Ans. 15–16), that while Nardello 2 may not
describe temperature as being the only result-effective variable, Nardello 2
demonstrates that it is a variable that is known to be alterable (increasing it)
to significantly reduce the reaction time.
Appellant argues dependent claims 3, 4, 6, 9, and 11 separately.
(Appeal Br. 17–19.) The Examiner explains why each argument fails to
overcome the obviousness argument (Ans. 16–20), and Appellant does not
respond. We agree with the Examiner that Appellant has not established
non-obviousness of these claims for the reasons expressed by the Examiner.
For the reasons discussed, we affirm the Examiner’s rejection of
claims 1–11 and 19–21.

Obviousness: Claims 12–18
The Examiner notes that although Emsenhuber discloses “that
hydroperoxides or peroxides can further react to give alcohols (see
paragraph 0019),” Emsenhuber does not disclose using “a reduction step of
the oxidized limonene to obtain the alcohols or . . . separat[ing] the reduced
reaction product by distillation.” (Final Action 7.)
The Examiner finds that Bain discloses a method for the
decomposition of peroxides that develop during an oxidation process by
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carrying out a reduction under alkaline conditions and then separating the
oxidation products via a physical process such as distillation. (Id.) The
Examiner further finds that Bain teaches that it was “known that terpenic
compounds are valuable ingredients of essential oils and are prized
individually and/or in combination as perfume ingredients (see column 1,
lines 29-34).” (Id. at 8.) The Examiner concludes that it would have been
obvious to produce an aroma composition for the oxidized limonene
compounds of Emesnhuber in light of Bain’s teaching (id.) and to use the
reduction process of Bain with Emsenhuber to obtain carveol, which is an
alcohol product of limonene (id. at 7).
We agree with the Examiner’s findings and conclusion of
obviousness. Bain teaches that it was known to oxidize limonene with
oxygen “and to work up such oxidation products to obtain carvone and
carveol” which are prized terpenic compounds. (Bain 1:29–44.)
Furthermore, Bain explains that it is “desirable to reduce . . . peroxides” in a
process of oxidizing limonene
Prior to attempts to separate the various oxidation products
from each other, since the peroxides are unstable and tend to
decompose in undesirable directions when heated as in
distilling them.
(Id. at 4:1–6.) Bain goes on to state:
Through reduction of the peroxides under neutral, preferably
alkaline conditions, we thus produce a limonene oxidation
mixture which is readily separable into epoxides, p-menthane
derivatives oxygenated at the 2-position and p-menthane
derivatives oxygenated at the 1-position. We avoid the various
decomposition products of the peroxides, oxides and other
sensitive compounds and thereby avoid formation of a
difficultly separable mixture containing large quantities of high
boiling, tar-like products and unsuited to clean separations.
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(Id. at 4:42–51.)
In light of Emsenhuber teaching oxidation of limonene in an oxidized
reaction mixture, we agree with the Examiner that it would have been
obvious to include a reduction step “to ensure that peroxides that would
hinder the separation of the desired oxidation products would be removed
prior to distillation.” (Ans. 21.)
Regarding Appellant’s arguments concerning Bain’s teaching of
neutralizing (Appeal Br. 22–23), we agree with and adopt the Examiner’s
response (Ans. 22) to which Appellant does not respond.
Regarding Appellant’s argument that Emsenhuber teaches away from
claims 15 and 18 (Appeal Br. 24–25), we agree with and adopt the
Examiner’s response (Ans. 22–23) to which Appellant does not respond.
Appellant does not separately argue claim 14.
In light of the foregoing, we affirm the Examiner’s rejection of claims
12–18 as being obvious from Emsenhuber and Bain.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1–11, 19–21 103 Emsenhuber,
Nardello 1,
Nardello 2
1–11, 19–21
12–18 103 Emsenhuber, Bain 12–18
Overall
Outcome
1–21

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TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED