111111111111111111111111141111111111j111121,1111111111111111111111111
`
`US008558018B2
`
`(12) United States Patent (cid:9)
`(12) United States Patent
`Sanborn (cid:9)
`Sanborn
`
`(54) OXIDATION OF FURFURAL COMPOUNDS
`(54) OXIDATION OF FURFURAL COMPOUNDS
`
`(75) Inventor: Alexandra Sanborn, Lincoln, IL (US)
`(75) Inventor: Alexandra Sanborn, Lincoln, IL (US)
`
`(73) Assignee: Archer Daniels Midland Company,
`(73) Assignee: Archer Daniels Midland Company,
`Decatur, IL (US)
`Decatur, IL (US)
`
`( * ) Notice:
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 191 days.
`U.S.C. 154(b) by 191 days.
`
`(21) Appl. No.:
`(21) Appl. No.:
`
`13/319,877
`13/319,877
`
`(22) PCT Filed:
`(22) PCT Filed:
`
`May 14, 2010
`May 14, 2010
`
`(86) PCT No.:
`(86) PCT No.:
`§ 371 (c)(1),
`§ 371 (0X1)’
`(2), (4) Date:
`(2), (4) Date:
`
`PCT/US2010/034856
`PCT/US2010/034856
`
`Nov. 10, 2011
`Nov. 10, 2011
`
`(87) PCT Pub. No.: W02010/132740
`(87) PCT Pub. No.: WO2010/132740
`
`PCT Pub. Date: Nov. 18, 2010
`PCT Pub. Date: Nov. 18, 2010
`
`(65)
`(65) (cid:9)
`
`Prior Publication Data
`Prior Publication Data
`
`US 2012/0059178 Al (cid:9)
`US 2012/0059178 A1
`
`Mar. 8, 2012
`Mar. 8, 2012
`
`Related U.S. Application Data
`Related US. Application Data
`(60) Provisional application No. 61/178,301, ?led on May
`(60) Provisional application No. 61/178,301, filed on May
`14, 2009.
`14, 2009.
`
`(2006.01)
`(2006.01)
`
`(51) Int. Cl.
`(51) Int. Cl.
`C07D 307/48
`C07D 307/48 (cid:9)
`(52) U.S. Cl.
`(52) US. Cl.
` 549/485
`USPC (cid:9)
`USPC ........................................................ .. 549/485
`(58) Field of Classification Search
`(58) Field of Classi?cation Search
`USPC (cid:9)
` 549/485
`USPC ........................................................ .. 549/485
`See application ?le for complete search history.
`See application file for complete search history.
`
`(56)
`(56)
`
`References Cited
`References Cited
`
`U.S. PATENT DOCUMENTS
`U.S. PATENT DOCUMENTS
`
`2,917,520 A
`2,917,520 A
`4,977,283 A
`4,977,283 A
`2003/0055271 Al
`2003/0055271 A1
`2006/0142599 Al
`2006/0142599 A1
`2010/0218415 Al
`2010/0218415 A1
`
`12/1959 Cope
`12/1959 Cope
`12/1990 Leupold et al.
`12/1990 Leupold et a1.
`3/2003 Grushin et al.
`3/2003 Grushin et al.
`6/2006 Sanborn et al.
`6/2006 Sanborn et a1.
`9/2010 Gruter et al.
`9/2010 Gruter et a1.
`
`OTHER PUBLICATIONS
`OTHER PUBLICATIONS
`
`Partenheimer et al; Synthesis of 2,5-Diformylfuran and Furan-2,5
`Partenheimer et al; Synthesis of 2,5-Diformylfuran and Furan-2,5-
`Dicarboxylic
`Acid
`by
`Catalytic
`Air-Oxidation
`of
`Dicarboxylic Acid by Catalytic Air-Oxidation of
`S-Hydroxymethylfurfural. Unexpectedly Selective Aerobic Oxida
`5-Hydroxymethylfurfural. Unexpectedly Selective Aerobic Oxida-
`tion of Benzyl Alcohol to Benzaldehyde with Metal/ Bromide Cata-
`tion of BenZyl Alcohol to Benzaldehyde with Metal/ Bromide Cata
`lysts; Adv. Synth Cata1.; 2001; 343, pp. 102-111.
`lysts; Adv. Synth Catal.; 2001; 343, pp. 102-111.
`Halliday et a1; One-Pot, Two-Step, Practical Catalytic Synthesis of
`Halliday et al; One-Pot, Two-Step, Practical Catalytic Synthesis of
`2,5-Diformylfuran from Fructose; Organic Letters; 2003, vol. 5, No.
`2,5-Diformylfuran from Fructose; Organic Letters; 2003, vol. 5, No.
`11, pp. 2003-2005.
`11, pp. 2003-2005.
`Bonner et al; The Iodine-catalysed Conversion of Sucrose into
`Bonner et al; The Iodine-catalysed Conversion of Sucrose into
`5-Hydroxy-methylfurfuraldehyde; Royal Holloway College, Sep.
`5-Hydroxy-methylfurfuraldehyde; Royal Holloway College, Sep.
`14, 1959, pp. 787-791.
`14, 1959, pp. 787-791.
`Lichtenthaler; Towards improving the utility of ketoses as organic
`Lichtenthaler; Towards improving the utility of ketoses as organic
`raw materials; Institute for Organic Chemistry, Germany; Apr. 15,
`raw materials; Institute for Organic Chemistry, Germany; Apr. 15,
`1998, pp. 69-89.
`1998, pp. 69-89.
`
`(10) Patent No.: (cid:9)
`(10) Patent N0.:
`(45) Date of Patent: (cid:9)
`(45) Date of Patent:
`
`US 8,558,018 B2
`US 8,558,018 B2
`Oct. 15, 2013
`Oct. 15, 2013
`
`Gandini et al; Furans in Polymer Chemistry; Prog. Polyrn. Sci., vol.
`Gandini et al; Furans in Polymer Chemistry; Prog. Polym. Sci., vol.
`22, pp. 1203-1379, 1997 Elsevier Science Ltd.
`22, pp. 1203-1379, 1997 Elsevier Science Ltd.
`KunZ; Hydroxymethylfurfural, A Possible Basic Chemical for Indus
`Kunz; Hydroxymethylfurfural, A Possible Basic Chemical for Indus-
`trial Intermediates; A. Fuchs (Ed.) Inulin and Inulin-containg Crops,
`trial Intermediates; A. Fuchs (Ed.) Inulin and Inulin-containg Crops,
`1993, Elsevier Science Publishers B.V., pp. 149-160.
`1993, Elsevier Science Publishers B.V., pp. 149-160.
`Antal et al; Mechanism of Formation of 5-(hydroxymethyl)-2
`Antal et al; Mechanism of Formation of 5-(hydroxymethyl)-2-
`Furalde-hyde from D-fructose and sucrose; Carbohydrate Research,
`Furalde-hyde from D-fructose and sucrose; Carbohydrate Research,
`1990, pp. 91-109, Elsevier Science Publishers B.V.
`1990, pp. 91-109, Elsevier Science Publishers B.V.
`Kuster et al; 5 -Hydroxymethylfurfural (HMF) A review focussing on
`Kuster et al; 5-Hydroxymethylfurfural (HMF) A review focussing on
`its manufacture; starch/stark 42 (1990) No. 8 pp. 314-321 VCH
`its manufacture; starch/stark 42 (1990) No. 8 pp. 314-321 VCH
`D-6940 Weinheim 1990.
`D-6940 Weinheim 1990.
`International Search Report; Korean Intellectual Property Of?ce,
`International Search Report; Korean Intellectual Property Office,
`Jan. 25, 2011, PCT/US2010/034856, pp. 1-3.
`Jan. 25, 2011, PCT/US2010/034856, pp. 1-3.
`Written Opinion; Korean Intellectual Property Of?ce, Jan. 24, 2011,
`Written Opinion; Korean Intellectual Property Office, Jan. 24, 2011,
`PCT/US2010/034856, pp. 1-3.
`PCT/US2010/034856, pp. 1-3.
`
`Primary Examiner - Taofiq A Solola
`Primary Examiner * Tao?q A Solola
`(74) Attorney, Agent, or Firm - Alexandra Sanborn; Mark
`(74) Attorney, Agent, or Firm * Alexandra Sanborn; Mark
`W. Roberts
`W. Roberts
`
`(57)
`(57) (cid:9)
`
`ABSTRACT
`ABSTRACT
`
`The disclosure pertains to a process for oxidation of furan
`The disclosure pertains to a process for oxidation of furan
`aldehydes such as 5-hydroxymethyl)furfural (HMF) and
`aldehydes such as 5-hydroxymethyl)furfural (HMF) and
`derivatives thereof such as 5-(alkoxymethyl)furfural (AMF),
`derivatives thereof such as 5-(alkoxymethyl)furfural (AMF),
`5-(aryloxymethyl)fur?1ral, 5-(cycloalkoxy-methyl)?1r?.1ral
`5-(aryloxymethyl)furfural, 5-(cycloalkoxy-methyl)furfural
`and 5-(alkoxycarbonyl)furfural compounds in the presence
`and 5-(alkoxycarbonyl)furfural compounds in the presence
`of dissolved oxygen and a Co(II), Mn(II), Ce(III) salt catalyst
`of dissolved oxygen and a Co(II), Mn(II), Ce(III) salt catalyst
`or mixtures thereof. The products from HMF can be selec-
`or mixtures thereof. The products from HMF can be selec
`tively chosen to be predominantly 2,5-diformylfuran (DFF),
`tively chosen to be predominantly 2,5-diformylfuran (DFF),
`particularly by inclusion of an aliphatic ketone, like methyl
`particularly by inclusion of an aliphatic ketone, like methyl
`ethyl ketone, or can be further oxidized to 2,5-furandicar-
`ethyl ketone, or can be further oxidized to 2,5-furandicar
`boxylic acid (FDCA) by the omission of methyl ethyl ketone
`boxylic acid (FDCA) by the omission of methyl ethyl ketone
`and inclusion of bromide. When the reactant is an ether
`and inclusion of bromide. When the reactant is an ether
`derivative of HMF the products are surprisingly ester deriva-
`derivative of HMF the products are surprisingly ester deriva
`tives where either both the ether and aldehyde functional
`tives where either both the ether and aldehyde functional
`groups have been oxidized or just the ether function group
`groups have been oxidized or just the ether function group
`thereby producing one or both of 5-ester-furan-2-acids (i.e.,
`thereby producing one or both of 5-ester-furan-2-acids (i.e.,
`5-alkoxycarbonylfurancarboxylic acids) or 5-ester-furan
`5-alkoxycarbonyl?lrancarboxylic acids) or 5-ester-furan
`aldehydes, (i.e., -alkoxycarbonyl?1r?.1rals a. k. a, 5-(alkoxy
`aldehydes, (i.e., -alkoxycarbonylfurfurals a. k. a, 5-(alkoxy-
`carbonyl)furfural). (I).
`carbonyl)furfural). (I).
`
`(I)
`(1)
`
`RO/WH —>
`ROWOH ROWH
`Ro/Vkorr
`
`RO
`
`OH
`
`0
`
`RO
`
`OH
`
`19 Claims, No Drawings
`19 Claims, No Drawings
`
`Petitioners' Exhibit 1004, Page 1 of 8
`
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`

`
`1
`1
`OXIDATION OF FURFURAL COMPOUNDS
`OXIDATION OF FURFURAL COMPOUNDS
`
`US 8,558,018 B2
`US 8,558,018 B2
`
`PRIORITY
`PRIORITY
`
`This application claims priority to Us. provisional appli
`This application claims priority to U.S. provisional appli-
`cation No. 61/178,301 ?led May 14, 2009, Which is incorpo
`cation No. 61/178,301 filed May 14, 2009, which is incorpo-
`rated herein by reference in its entirety.
`rated herein by reference in its entirety.
`
`FIELD OF INVENTION
`FIELD OF INVENTION
`
`2
`2
`and tends to co-precipitate With side products. It Would be
`and tends to co-precipitate with side products. It would be
`beneficial if an FDCA precursor could be made that is easy to
`bene?cial if an FDCA precursor could be made that is easy to
`separate and Which could subsequently be converted to
`separate and which could subsequently be converted to
`FDCA in a different reaction. Also it would be beneficial to
`FDCA in a different reaction. Also it Would be bene?cial to
`5 find other routes to selective preparation of DFF versus
`?nd other routes to selective preparation of DFF versus
`FDCA by oxidative methods. The present invention provides
`FDCA by oxidative methods. The present invention provides
`for these and other needs that Will be apparent from the
`for these and other needs that will be apparent from the
`description that folloWs.
`description that follows.
`
`10
`
`The invention pertains to processes for oxidation of furan
`The invention pertains to processes for oxidation of furan
`aldehydes such as 5-(hydroxymethyl)furfural (HMF) to
`aldehydes such as 5-(hydroxymethyl)furfural (HMF) to
`selectively form 2,5-diformylfuran (DFF) and to oxidation of
`selectively form 2,5-diformylfuran (DFF) and to oxidation of
`ether derivatives of HMF such as 5-(alkoxymethyl)furfural
`ether derivatives of HMF such as 5-(alkoxymethyl)furfural
`(AMF), 5-(aryloxymethyl)furfural, 5-(cycloalkoxymethyl)
`(AMF), 5-(aryloxymethyl)furfural, 5-(cycloalkoxymethyl) 15
`furfural and 5-(acyloxymethyl)furfural compounds to form
`furfural and 5-(acyloxymethyl)furfural compounds to form
`ester-acid derivatives of HMF, particularly 5-(alkoxycarbo
`ester-acid derivatives of HMF, particularly 5-(alkoxycarbo-
`nyl)furan-2-carboxylic acids. The oxidations are done or in
`nyl)furan-2-carboxylic acids. The oxidations are done or in
`the presence of dissolved oxygen and a Co(II), Mn(II), Ce(III)
`the presence of dissolved oxygen and a Co (II), Mn(II), Ce(III)
`salt catalyst or mixtures thereof with or without bromide and 20
`salt catalyst or mixtures thereof With or Without bromide and
`20
`with or without an aliphatic ketone to selectively form the
`With or Without an aliphatic ketone to selectively form the
`desired compounds. The products can be further oxidiZed for
`desired compounds. The products can be further oxidized for
`form 2,5 furandicarboxylic acid (FDCA).
`form 2,5 furandicarboxylic acid (FDCA).
`
`BACKGROUND (cid:9)
`BACKGROUND
`
`25
`25
`
`HMF is an important compound with many industrial
`HMF is an important compound With many industrial
`applications such as use in polymers, solvents, surfactants,
`applications such as use in polymers, solvents, surfactants,
`pharmaceuticals, and plant protection agents. HoWever, the
`pharmaceuticals, and plant protection agents. However, the
`oxidation derivatives of HMF also have important commer- 30
`oxidation derivatives of HMF also have important commer
`30
`cial value. For example, 2,5 diformylfuran (DFF) has various
`cial value. For example, 2,5 diformylfuran (DFF) has various
`useful applications such as a monomer; as a starting material
`useful applications such as a monomer; as a starting material
`for the synthesis of drugs, antifungal agents, nematocides and
`for the synthesis of drugs, antifungal agents, nematocides and
`ligands; in photography; and as a cross-linking agent for
`ligands; in photography; and as a cross-linking agent for
`polyvinyl alcohol. 2,5 furandicarboxylic acid a.k.a. furandi
`polyvinyl alcohol. 2,5 furandicarboxylic acid a.k.a. furandi- 35
`35
`acid (FDCA a.k.a FDA) represents one key intermediate sub-
`acid (FDCA a.k.a FDA) represents one key intermediate sub
`stance and is a suitable starting source for the formation of
`stance and is a suitable starting source for the formation of
`various furan monomers required for the preparation of non-
`various furan monomers required for the preparation of non
`petroleum-derived polymeric materials.
`petroleum-derived polymeric materials.
`Many methods have been proposed for making DFF and
`Many methods have been proposed for making DFF and 40
`40
`FDCA. HoWever, these reactions provide loW yields, poor
`FDCA. However, these reactions provide low yields, poor
`selectivity and are not environmentally friendly. For example,
`selectivity and are not environmentally friendly. For example,
`it is known that the synthesis of DFF from fructose can be
`it is knoWn that the synthesis of DFF from fructose can be
`done in a two step process, namely, by dehydration of fructose
`done in a tWo step process, namely, by dehydration of fructose
`in a high boiling solvent such as dimethylsulfoxide (DMSO) 45
`in a high boiling solvent such as dimethylsulfoxide (DMSO)
`45
`to form HMF, folloWed by in situ catalytic air oxidation also
`to form HMF, followed by in situ catalytic air oxidation also
`in the presence of DMSO to form a mixture of DFF, FDCA
`in the presence of DMSO to form a mixture of DFF, FDCA
`and various other reaction side products.
`and various other reaction side products.
`Also, it has been shown that DFF or FDCA could be made
`Also, it has been shoWn that DFF or FDCA could be made
`from HMF by oxidation in the presence of dissolved oxygen so
`from HMF by oxidation in the presence of dissolved oxygen
`50
`at about 1000 psi, and a catalyst system containing Co(II),
`at about 1000 psi, and a catalyst system containing Co(II),
`Mn(II), and a Br salt preferentially also including Zi (W.
`Mn(II), and a Br salt preferentially also including Zi (W.
`Partenhemier & V Grushin: Adv. Synlh. Calal. (2001) 343,
`Partenhemier & V Grushin: Adv. Synth. Catal. (2001) 343,
`102-111). However the selectivity for DFF was at most 69%
`102-11 1). HoWever the selectivity for DFF Was at most 69%
`in a catalyst system of Co/Mn/Br, and at most 73%. in a 55
`in a catalyst system of Co/Mn/Br, and at most 73%. in a
`55
`catalyst system of Co/Mn/Br/Zr. The best selectivity for
`catalyst system of Co/Mn/Br/Zr. The best selectivity for
`FDCA was 73% in a catalyst system of Co/Mn/Br/Zr and at
`FDCA Was 73% in a catalyst system of Co/ Mn/Br/ Zr and at
`most about 35% with the same catalyst system but without the
`mo st about 3 5% With the same catalyst system but Without the
`Zr. The ability to convert HMF into one predominant oxida-
`Zr. The ability to convert HMF into one predominant oxida
`tion product is dif?cult due to the reactivity of the aldehyde
`tion product is difficult due to the reactivity of the aldehyde 60
`60
`and alcohol moieties of the HMF molecule. In the above
`and alcohol moieties of the HMF molecule. In the above
`mentioned reference, selectivity between DFF and FDCA as
`mentioned reference, selectivity betWeen DFF and FDCA as
`the predominant product Was affected by using loWer reaction
`the predominant product was affected by using lower reaction
`temperatures (SO-75° C.) for making DFF, and higher reac
`temperatures (50-75° C.) for making DFF, and higher reac-
`tion temperatures for making FDCA (typically 100-125° C.).
`tion temperatures for making FDCA (typically 100-125° C.). 65
`65
`FDCA is a difficult product to handle. It tends to precipitate
`FDCA is a dif?cult product to handle. It tends to precipitate
`in solvents used for oxidation when the temperature is raised
`in solvents used for oxidation When the temperature is raised
`
`SUMMARY OF THE INVENTION
`SUMMARY OF THE INVENTION
`
`The present invention is based at least in-part, on the sur-
`The present invention is based at least in-part, on the sur
`prising discovery that 5-ethers of HMF canbe simultaneously
`prising discovery that 5-ethers of HMF can be simultaneously
`oxidiZed at the ether linkage and at aldehyde to form 5-ester
`oxidized at the ether linkage and at aldehyde to form 5-ester
`furanic acids, (i.e., 5-alkoxycarbonylfurancarboxylic acids,
`furanic acids, (i.e., 5-alkoxycarbonylfurancarboxylic acids,
`furan-2,5-dicarboxylic acid monoesters, a.k.a. 5-alkoxycar
`furan-2,5-dicarboxylic acid monoesters, a.k.a. 5-alkoxycar-
`bonylfuran 2-carboxylic acids) using a catalyst system com
`bonylfuran 2-carboxylic acids) using a catalyst system com-
`prised of Co(II), Mn(II) and Ce(III) salts. These ester com-
`prised of Co(II), Mn(II) and Ce(III) salts. These ester com
`pounds are easy to separate by conventional solvent
`pounds are easy to separate by conventional solvent
`extraction or distillation and can be subsequently converted to
`extraction or distillation and can be subsequently converted to
`FDCA under mild hydrolysis conditions.
`FDCA under mild hydrolysis conditions.
`It also has been surprisingly found that under similar reac-
`It also has been surprisingly found that under similar reac
`tion conditions, HMF can be selectively converted to DFF by
`tion conditions, HMF can be selectively converted to DFF by
`the inclusion of a aliphatic ketone, exempli?ed by methyl
`the inclusion of a aliphatic ketone, exemplified by methyl
`ethyl ketone (MEK). The omission of bromide from the reac-
`ethyl ketone (MEK). The omission of bromide from the reac
`tion mixture also favors selective production of DFF. Con
`tion mixture also favors selective production of DFF. Con-
`versely, it also has been found that FDCA can be selectively
`versely, it also has been found that FDCA can be selectively
`made from HMF at greater than 40% by the inclusion of
`made from HMF at greater than 40% by the inclusion of
`bromide in the reaction mixture. It also has been found that
`bromide in the reaction mixture. It also has been found that
`selective production of FDCA can occur without need for a
`selective production of FDCA can occur Without need for a
`Zirconium co-catalyst in the reaction mixture. It also has been
`zirconium co-catalyst in the reaction mixture. It also has been
`found that HMF can be converted to FDCA using only cobalt,
`found that HMF can be converted to FDCA using only cobalt,
`or only cerium salts in the presence of bromide, without the
`or only cerium salts in the presence of bromide, Without the
`need for manganese or zirconium co-catalyst.
`need for manganese or Zirconium co-catalyst.
`More speci?cally, the present invention provides methods
`More specifically, the present invention provides methods
`of oxidiZing furan aldehydes that includes heating the furan
`of oxidizing furan aldehydes that includes heating the furan
`aldehyde in a reaction mixture comprising a solvent contain-
`aldehyde in a reaction mixture comprising a solvent contain
`ing dissolved oxygen and at least one catalyst selected from
`ing dissolved oxygen and at least one catalyst selected from
`the group consisting of Co(II), Mn(II) and Ce(III) salts. If the
`the group consisting of Co(II), Mn(II) and Ce(III) salts. If the
`furan aldehyde is -5-(hydroxymethyl)furfural., the reaction
`furan aldehyde is -5-(hydroxymethyl)furfural., the reaction
`mixture includes a aliphatic ketone which helps make the
`mixture includes a aliphatic ketone Which helps make the
`predominant reaction product of diformylfuran. If the furan
`predominant reaction product of diformylfuran. If the furan
`aldehyde is a 5-ether of the furan aldehyde, the predominant
`aldehyde is a 5-ether of the furan aldehyde, the predominant
`reaction product is at least one of a 5-ester furan 2-acid and a
`reaction product is at least one of a 5-ester furan 2-acid and a
`5-(alkoxycarbonyl)?.1r?.1ral. Moreover, if the furan aldehyde
`5-(alkoxycarbonyl)furfural. Moreover, if the furan aldehyde
`is a 5-(alkoxycarbonyl)furfural the predominant reaction
`is a 5-(alkoxycarbonyl)furfural the predominant reaction
`product is the 5-ester furan 2-carboxylic acid, meaning that
`product is the 5-ester furan 2-carboxylic acid, meaning that
`under prolonged reaction conditions, even if 5 -(alkoxycarbo-
`under prolonged reaction conditions, even if 5-(alkoxycarbo
`nyl)furfural or 5-(alkoxymethyl)furoic acid is made from the
`nyl)furfural or 5-(alkoxymethyl)furoic acid is made from the
`furan ether aldehyde, intermediate furan can further be oxi-
`furan ether aldehyde, intermediate furan can further be oxi
`dized to the ester-acid derivative. The 5-ether of the furan
`diZed to the ester-acid derivative. The 5-ether of the furan
`aldehyde canbe any ether, especially including a 5-(alkoxym
`aldehyde can be any ether, especially including a 5-(alkoxym-
`ethyl)furfural, a 5-(aryloxymethyl)furfural, and a 5-(cy-
`ethyl)furfural, a 5-(aryloxymethyl)furfural, and a 5-(cy
`cloalkoxymethyl)furfural. Examples are provided When the
`cloalkoxymethyl)furfural. Examples are provided when the
`furan aldehyde is HMF, and where the 5-ether of the furan
`furan aldehyde is HMF, and Where the 5-ether of the furan
`aldehyde is 5 -(acetoxymethyl)furfural and 5 -(butoxymethyl)
`aldehyde is 5-(acetoxymethyl)furfural and 5-(butoxymethyl)
`furfural.
`furfural.
`Under typical conditions the reaction mixture is heated to a
`Under typical conditions the reaction mixture is heated to a
`temperature of between 80° C. and 130° C. at a pressure of
`temperature of betWeen 80° C. and 130° C. at a pressure of
`oxygen or air of about 600- to about 1000 psi for a time
`oxygen or air of about 600- to about 1000 psi for a time
`suf?cient to form the predominant reaction product. Prefer
`sufficient to form the predominant reaction product. Prefer-
`ably the temperature is between 100° C. and 125° C., and
`ably the temperature is betWeen 100° C. and 125° C., and
`most typically is about 120° C. Air or oxygen can be used
`most typically is about 120° C. Air or oxygen can be used
`under the pressure conditions to supply oxygen to the reaction
`under the pres sure conditions to supply oxygen to the reaction
`mixture. In exemplary embodiments, the reaction mixture
`mixture. In exemplary embodiments, the reaction mixture
`contains acetic acid as a principle solvent.
`contains acetic acid as a principle solvent.
`
`Petitioners' Exhibit 1004, Page 2 of 8
`
`

`
`US 8,558,018 B2
`US 8,558,018 B2
`
`4
`3
`4
`3
`rotor. As a result, there is frequent shut down time making the
`In most desirable embodiments, at least 90% of the furan
`rotor. As a result, there is frequent shut doWn time making the
`In most desirable embodiments, at least 90% of the furan
`Operation inefficient, Prior work has been performed with
`aldehyde is oxidiZed into reaction products, and the predomi-
`aldehyde is oxidized into reaction products, and the predomi-
`operation inefficient. Prior work has been performed with
`nant reaction product is at least 80% of the reaction products.
`distillation and the addition of a non-volatile solvent like
`Ham reaction Productis atleast 80% Ofthe reaction Products
`distillation and the addition of a non-volatile solvent like
`When ester furan aldehydes are used, the predominant reac-
`PEG_600 to prevent the buildup of Solid humin polymem
`When ester furan aldehydes are used, the predom1nant reac-
`PEG-600 to prevent the buildup of solid humin polymers.
`tion product is a 5-ester furan 2-carboxylic acid which can be
`tion product is a 5-ester furan 2-carboxylic acid Which can be
`5 Unfortunately, the use of polyglycols leads to the formation
`5 Unfortunately, the use of polyglycols leads to the formation
`collected by precipitation from, or evaporation of the reaction
`collected by precipitation from, or evaporation of the reaction
`of HMF-PEG ethers.
`mixture in a first purification step. In a second purification
`of HMRPEG, ether?
`_
`_
`_
`_
`mixture in a ?rst puri?cation step. In a second puri?cation
`Due to the instability and limited applications of HMF, the
`_ Due to the lnetablhty andhmlted aPPhCaUOHS OfHMF’ the
`step, the precipitate is dissolved in a solvent in Which the
`step, the precipitate is dissolved in a solvent in which the
`inventor's studies have broadened to include the synthesis
`1nventor’s stud1es have broadened to Include the synthesis
`predominant product has higher Solubility than FDCA in a
`predominant product has higher solubility than FDCA. in a
`and purification of a variety of HMF derivatives. In a first
`and Puri?cation Of a variety of HMF derivatives- In a ?rst
`second puri?cation step. Suitable solvents include, but are not
`second purification step. Suitable solvents include, but are not
`10 embodiment, derivatives of particular interest are the oxi-
`limited to: ethyl acetate, dimethylformamide, dimethylac- 10 embodiment, derivatives of particular interest are the oxi
`limited to: ethyl acetate, dimethylformamide, dimethylac-
`etate, tetrahydrofuran, dioxane, methyl ethyl ketone, methyl
`diZed forms of HMF, in Which HMF is selectively oxidized to
`etate, tetrahydrofuran, dioxane, methyl ethyl ketone, methyl
`dized forms of HMF, in which HMF is selectively oxidized to
`isobutyl ketone, acetonitrile, methyltetrahydrofuran, and
`form 2,5-diformylfuran (DFF) or 2,5-furandicarboxylic acid
`isobutyl ketone, acetonitrile, methyltetrahydrofuran, and
`form 2,5-diformylfuran (DFF) or 2,5-furandicarboxylic acid
`Cl -C6 alcohols.
`(FDCA).
`C1-C6 alcohols.
`(FDCA).
`
`o
`
`o
`
`H
`
`0
`O
`\ /
`
`DFF
`DFF
`
`Co/Mn, NaBr, AcOH,
`Co/Mn, MEK, AcOH,
`O
`Co/Mn, NaBr, AcOH,
`Co/Mn, MEK, AcOH,
`<— —>
`HO
`120 c., 1000 psi 02 HO
`H 100 c, 1000 psi 02
`HO
`\ /
`120 C., 1000 psi 02 (cid:9)
`100 C., 1000 psi 02
`HO
`
`H
`H (cid:9)
`
`O
`0
`\ /
`
`OH
`OH
`
`O
`0
`
`o
`
`0
`o
`
`(11)
`
`HMF
`HMF
`
`FDCA
`FDCA
`
`The catalyst salt can have any typical anion partner, such as
`Other embodiments of particular interest are oxidation of
`Other embodiments of particular interest are oxidation of
`The catalyst salt can have any typical anion partner, such as
`ethers of HMF a.k.a, 5-alkoxymethylfurfurals.(AMP). In past
`acetate, acetate hydrate, bromide, chloride, ?uoride, iodide,
`acetate, acetate hydrate, bromide, chloride, fluoride, iodide,
`ethers of HMF a.k.a, 5-alkoxymethylfurfurals.(AMF). In past
`alkoxide, azide, oxalate, carbonate, carboxylate, hydroxide,
`alkOXide, aZide, Oxalate, Carbonate, carboxylates hydroxide, 25 Work, the inventor has been able to obtain overall high yields
`work, the inventor has been able to obtain overall high yields
`25
`nitrate, borate, oxide, acetylacetonate and mixtures thereof.
`nitrate, borate, oxide, acetylacetonate and mixtures thereof.
`Of AMP by acid dehydration of fructose using Crystalline
`of AMF by acid dehydration of fructose using crystalline
`In certain practices the reaction mixture can include CO2
`In certain practices the reaction mixture can include CO2
`fructose and even high fructose Corn Syrup (HFCS) in the ?rst
`fructose and even high fructose corn syrup (HFCS) in the first
`expanded in the principle solvent of the reactions mixture, for
`expanded in the Principle Solvent Ofthe reactions mixture’ for
`step shoWn in the reaction beloW. The ether derivatives can be
`step shown in the reaction below. The ether derivatives can be
`example, CO2 expanded acetic acid. The CO2 should be
`example’ CO2 expanded acetic acid' The CO2 Should be
`easily formed, are more stable, and can be separated making
`easily formed, are more stable, and can be separated making
`expanded in the solvent at a pressure of at least 100 psi. Under
`expanded in the solvent at a pressure of at least 100 psi. Under
`30 them even more useful than HMF itself.
`30 them even more useful than HMF itself.
`typical conditions, the oxygen is provided by oxygen gas or
`typical conditions, the oxygen is provided by oxygen gas or
`With the present invention, however, oxidation ofAMF can
`With the present invention, hoWever, oxidation of AMP can
`air dissolved in the solvent at a pressure of at least 200 psi and
`air dissolved in the solvent at a pressure of at least 200 psi and
`also readily be achieved using the same catalyst as used for
`CO2 is expanded in the Solvent at a pressure of at 100 psi’
`also readily be achieved using the same catalyst as used for
`CO2 is expanded in the solvent at a pressure of at 100 psi,
`typically 100-200 psi
`oxidiZing HMF. The major resulting product is surprisingly
`oxidizing HMF. The major resulting product is surprisingly
`typically 100-200 psi.
`found to be ester derivative a 5-(alkoxycarbonyl)furancar-
`The reaction mixture may also include bromide When it is
`found to be ester derivative a 5-(a1kOXyCarbOny1)?1ranCar
`The reaction mixture may also include bromide when it is
`35 boxcylic acid (AcMF) where the alkoxymethyl ether linkage
`desirable to form FDCA as a co-product of the oxidiZing in 35 boxcylic acid (ACMF) Where the alkoxymethyl ether linkage
`desirable to form FDCA as a co-product of the oxidizing in
`has been oxidized to an ester and while the furan aldehyde is
`which case, under prolonged conditions, FDCA can become
`Which case, under prolonged conditions, FDCA can become
`has been oxidiZed to an ester and While the furan aldehyde is
`the predominant product when HMF, or even the ether deriva-
`oxidized to the acid shown at the right of the reaction below.
`the predominant product When HMF, or even the ether deriva-
`oxidiZed to the acid shoWn at the right of the reaction beloW.
`tive of HMF is the reactant. Conversely, and the reaction
`tive of HMF is the reactant. Conversely, and the reaction
`mixture omits bromide, contains methyl ethyl ketone with
`mixture omits bromide, contains methyl ethyl ketone With 40
`40
`HMF as the reactant, the predominant reaction product is
`HMF as the reactant, the predominant reaction product is
`DFF.
`DFF
`~
`
`In
`(
`)
`
`O
`
`CHZOH
`
`DETAILED DESCRIPTION OF THE INVENTION
`DETAILED DESCRIPTION OF THE INVENTION
`
`45
`The invention is directed to a low cost and environmentally
`The invention is directed to a loW cost and environmentally 45
`friendly method for oxidation of a furfural compounds in the
`friendly method for oxidation of a furfural compounds in the
`presence of oxygen in a reaction mixture containing at least
`presence of oxygen in a reaction mixture containing at least
`one of Co(II), Mn(II), Ce(III) salt catalysts according to the
`one of Co(II), Mn(II), Ce(III) salt catalysts according to the
`folloWing reaction scheme:
`following reaction scheme:
`
`HO
`
`HOHZC
`HO
`
`Fructose
`Fructose
`
`ROH, H2SO4
`w,
`1 h, 160 c.
`1 h, 160 C.
`
`0
`
`(I)
`(I)
`
`RWH <— ROmiH —> R0
`
`\ /
`
`OH
`
`Wherein R represents H, alkyl, aryl, acyl, cycloalkyl or
`wherein R represents H, alkyl, aryl, acyl, cycloalkyl or
`alkylcarbonyl.
`alkylcarbonyl.
`The purification of HMF has proved to be a troublesome
`The puri?cation of HMF has proved to be a troublesome
`operation. On long exposure to temperatures at which the
`operation. On long exposure to temperatures at Which the
`desired product can be distilled, HMF and impurities associ-
`desired product can be distilled, HMF and impurities associ-
`ated With the synthetic mixture, tend to form tarry degrada-
`ated with the synthetic mixture, tend to form tarry degrada-
`tion products. Because of this heat instability, a falling film
`tion products. Because of this heat instability, a falling ?lm 65
`65
`vacuum still must be used. Even in such an apparatus, resin-
`vacuum still must be used. Even in such an apparatus, resin-
`ous solids form on the heating surface causing a stalling in the
`ous solids form on the heating surface causing a stalling in the
`
`60
`60
`
`RO
`RO
`
`O
`
`\ /
`
`AMF
`AMF
`
`-continued
`-continued
`0
`O
`
`H
`
`Co/Mn, NaBr, AcOH,
`Co/Mn, NaBr, AcOH,
`—>
`100 C., 1000 psi 02
`100 C., 1000 psi 02
`
`Petitioners' Exhibit 1004, Page 3 of 8
`
`(cid:9)
`(cid:9)
`(cid:9)
`(cid:9)
`

`
`US 8,558,018 B2
`US 8,558,018 B2
`
`5
`5
`-continued
`-continued
`
`0
`
`0
`
`O
`
`RO
`RO
`
`OH
`OH
`
`AcMFA
`AcMFA
`
`5
`
`10
`
`6
`6
`rapidly. Bromide is favored for the production of FDCA,