AU2001293968A1 - Oxidation of alkyl-aromatic compounds - Google Patents
Oxidation of alkyl-aromatic compoundsInfo
- Publication number
- AU2001293968A1 AU2001293968A1 AU2001293968A AU9396801A AU2001293968A1 AU 2001293968 A1 AU2001293968 A1 AU 2001293968A1 AU 2001293968 A AU2001293968 A AU 2001293968A AU 9396801 A AU9396801 A AU 9396801A AU 2001293968 A1 AU2001293968 A1 AU 2001293968A1
- Authority
- AU
- Australia
- Prior art keywords
- acid
- oxidation
- alkyl
- ionic liquid
- nitrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000007254 oxidation reaction Methods 0.000 title claims description 32
- 230000003647 oxidation Effects 0.000 title claims description 31
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 54
- 238000000034 method Methods 0.000 claims description 41
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 24
- 239000002608 ionic liquid Substances 0.000 claims description 23
- 239000002253 acid Substances 0.000 claims description 17
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 16
- 229910017604 nitric acid Inorganic materials 0.000 claims description 16
- 239000007800 oxidant agent Substances 0.000 claims description 14
- URLKBWYHVLBVBO-UHFFFAOYSA-N Para-Xylene Chemical group CC1=CC=C(C)C=C1 URLKBWYHVLBVBO-UHFFFAOYSA-N 0.000 claims description 13
- 150000001450 anions Chemical class 0.000 claims description 13
- AFVFQIVMOAPDHO-UHFFFAOYSA-N Methanesulfonic acid Chemical compound CS(O)(=O)=O AFVFQIVMOAPDHO-UHFFFAOYSA-N 0.000 claims description 12
- 229910052757 nitrogen Inorganic materials 0.000 claims description 12
- 229910002651 NO3 Inorganic materials 0.000 claims description 11
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 11
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 11
- IQQRAVYLUAZUGX-UHFFFAOYSA-N 1-butyl-3-methylimidazolium Chemical compound CCCCN1C=C[N+](C)=C1 IQQRAVYLUAZUGX-UHFFFAOYSA-N 0.000 claims description 10
- 125000000217 alkyl group Chemical group 0.000 claims description 9
- 150000001768 cations Chemical class 0.000 claims description 9
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 8
- 229910052717 sulfur Inorganic materials 0.000 claims description 8
- 239000011593 sulfur Substances 0.000 claims description 8
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 7
- 230000002378 acidificating effect Effects 0.000 claims description 7
- 229910001882 dioxygen Inorganic materials 0.000 claims description 7
- 239000008096 xylene Substances 0.000 claims description 7
- 150000001491 aromatic compounds Chemical class 0.000 claims description 6
- 239000003054 catalyst Substances 0.000 claims description 5
- 229940098779 methanesulfonic acid Drugs 0.000 claims description 5
- 238000000859 sublimation Methods 0.000 claims description 5
- 230000008022 sublimation Effects 0.000 claims description 5
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 claims description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 4
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 claims description 4
- 229910052787 antimony Inorganic materials 0.000 claims description 4
- 229910052785 arsenic Inorganic materials 0.000 claims description 4
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims description 4
- 125000003118 aryl group Chemical group 0.000 claims description 4
- 238000004821 distillation Methods 0.000 claims description 4
- 150000002978 peroxides Chemical class 0.000 claims description 4
- 229910052698 phosphorus Inorganic materials 0.000 claims description 4
- 239000011574 phosphorus Substances 0.000 claims description 4
- 229910052711 selenium Inorganic materials 0.000 claims description 4
- 239000011669 selenium Substances 0.000 claims description 4
- 238000000926 separation method Methods 0.000 claims description 4
- 229910052714 tellurium Inorganic materials 0.000 claims description 4
- PORWMNRCUJJQNO-UHFFFAOYSA-N tellurium atom Chemical compound [Te] PORWMNRCUJJQNO-UHFFFAOYSA-N 0.000 claims description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 claims description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 3
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 claims description 3
- OUUQCZGPVNCOIJ-UHFFFAOYSA-M Superoxide Chemical compound [O-][O] OUUQCZGPVNCOIJ-UHFFFAOYSA-M 0.000 claims description 3
- DTQVDTLACAAQTR-UHFFFAOYSA-M Trifluoroacetate Chemical compound [O-]C(=O)C(F)(F)F DTQVDTLACAAQTR-UHFFFAOYSA-M 0.000 claims description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 238000002425 crystallisation Methods 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 238000001256 steam distillation Methods 0.000 claims description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 2
- WTKZEGDFNFYCGP-UHFFFAOYSA-O Pyrazolium Chemical compound C1=CN[NH+]=C1 WTKZEGDFNFYCGP-UHFFFAOYSA-O 0.000 claims description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 2
- 238000010533 azeotropic distillation Methods 0.000 claims description 2
- 229910052797 bismuth Inorganic materials 0.000 claims description 2
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 2
- 229910052796 boron Inorganic materials 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims description 2
- 229910052736 halogen Inorganic materials 0.000 claims description 2
- 150000002367 halogens Chemical class 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-M hydrogensulfate Chemical compound OS([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-M 0.000 claims description 2
- 150000004715 keto acids Chemical class 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims description 2
- -1 organic acid anion Chemical class 0.000 claims description 2
- XYFCBTPGUUZFHI-UHFFFAOYSA-O phosphonium Chemical compound [PH4+] XYFCBTPGUUZFHI-UHFFFAOYSA-O 0.000 claims description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-O pyridinium Chemical compound C1=CC=[NH+]C=C1 JUJWROOIHBZHMG-UHFFFAOYSA-O 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- 238000000638 solvent extraction Methods 0.000 claims description 2
- 150000003464 sulfur compounds Chemical class 0.000 claims description 2
- 238000004808 supercritical fluid chromatography Methods 0.000 claims description 2
- 238000000194 supercritical-fluid extraction Methods 0.000 claims description 2
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims 1
- 150000001721 carbon Chemical group 0.000 claims 1
- 239000007795 chemical reaction product Substances 0.000 claims 1
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 claims 1
- 150000002823 nitrates Chemical class 0.000 claims 1
- 150000002891 organic anions Chemical class 0.000 claims 1
- 238000002360 preparation method Methods 0.000 claims 1
- 239000007858 starting material Substances 0.000 claims 1
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 18
- 238000006243 chemical reaction Methods 0.000 description 17
- 238000010992 reflux Methods 0.000 description 16
- 239000000203 mixture Substances 0.000 description 13
- 239000000047 product Substances 0.000 description 13
- 239000005711 Benzoic acid Substances 0.000 description 10
- 235000010233 benzoic acid Nutrition 0.000 description 10
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 description 8
- KWOLFJPFCHCOCG-UHFFFAOYSA-N Acetophenone Chemical compound CC(=O)C1=CC=CC=C1 KWOLFJPFCHCOCG-UHFFFAOYSA-N 0.000 description 6
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 6
- 238000004817 gas chromatography Methods 0.000 description 6
- ODLMAHJVESYWTB-UHFFFAOYSA-N propylbenzene Chemical compound CCCC1=CC=CC=C1 ODLMAHJVESYWTB-UHFFFAOYSA-N 0.000 description 6
- ZWLPBLYKEWSWPD-UHFFFAOYSA-N o-toluic acid Chemical compound CC1=CC=CC=C1C(O)=O ZWLPBLYKEWSWPD-UHFFFAOYSA-N 0.000 description 5
- 238000000023 Kugelrohr distillation Methods 0.000 description 4
- LPNBBFKOUUSUDB-UHFFFAOYSA-N p-toluic acid Chemical compound CC1=CC=C(C(O)=O)C=C1 LPNBBFKOUUSUDB-UHFFFAOYSA-N 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- ZPTVNYMJQHSSEA-UHFFFAOYSA-N 4-nitrotoluene Chemical compound CC1=CC=C([N+]([O-])=O)C=C1 ZPTVNYMJQHSSEA-UHFFFAOYSA-N 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- VLZLOWPYUQHHCG-UHFFFAOYSA-N nitromethylbenzene Chemical compound [O-][N+](=O)CC1=CC=CC=C1 VLZLOWPYUQHHCG-UHFFFAOYSA-N 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- PUHVBRXUKOGSBC-UHFFFAOYSA-M 1-butyl-3-methylimidazol-3-ium;methanesulfonate Chemical compound CS([O-])(=O)=O.CCCC[N+]=1C=CN(C)C=1 PUHVBRXUKOGSBC-UHFFFAOYSA-M 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical class N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 238000005481 NMR spectroscopy Methods 0.000 description 2
- 150000001299 aldehydes Chemical class 0.000 description 2
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 150000002576 ketones Chemical class 0.000 description 2
- 229940078552 o-xylene Drugs 0.000 description 2
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 2
- KRIOVPPHQSLHCZ-UHFFFAOYSA-N propiophenone Chemical compound CCC(=O)C1=CC=CC=C1 KRIOVPPHQSLHCZ-UHFFFAOYSA-N 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- PBWHJRFXUPLZDS-UHFFFAOYSA-N (1-Ethylpropyl)benzene Chemical compound CCC(CC)C1=CC=CC=C1 PBWHJRFXUPLZDS-UHFFFAOYSA-N 0.000 description 1
- WPHIMOZSRUCGGU-UHFFFAOYSA-N 1-butyl-3-methylimidazol-3-ium;nitrate Chemical compound [O-][N+]([O-])=O.CCCCN1C=C[N+](C)=C1 WPHIMOZSRUCGGU-UHFFFAOYSA-N 0.000 description 1
- 208000033962 Fontaine progeroid syndrome Diseases 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- JAWGVVJVYSANRY-UHFFFAOYSA-N cobalt(3+) Chemical compound [Co+3] JAWGVVJVYSANRY-UHFFFAOYSA-N 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002290 gas chromatography-mass spectrometry Methods 0.000 description 1
- GPSDUZXPYCFOSQ-UHFFFAOYSA-N m-toluenecarboxylic acid Natural products CC1=CC=CC(C(O)=O)=C1 GPSDUZXPYCFOSQ-UHFFFAOYSA-N 0.000 description 1
- 238000007248 oxidative elimination reaction Methods 0.000 description 1
- KHIWWQKSHDUIBK-UHFFFAOYSA-N periodic acid Chemical compound OI(=O)(=O)=O KHIWWQKSHDUIBK-UHFFFAOYSA-N 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
- C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
- C07C51/265—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting having alkyl side chains which are oxidised to carboxyl groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/27—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with oxides of nitrogen or nitrogen-containing mineral acids
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Catalysts (AREA)
Description
Oxidation of alkyl-aromatic compounds
This invention relates to a process for the oxidation of aromatic compounds such as toluene and xylene. The oxidation of compounds such as toluene and xylene are important reactions and are carried,-out on. a .large scale. The products of the. oxidatάon reactions'; e.g. terephthalic acid, are widely used.'in the polyπier industry.
Various methods exist for the oxidation of toluene, including oxidation with dioxygen, using a cobalt (III)1,2 catalyst, periodate,3 air using Cs5[Si ιι039Ru(III) (H20) ] .7 H20 as a catalyst (59% yield),4 hypochlorite catalysed by Ru (VIII) oxide tetroxide in [BuN]Br.5 These methods work well, but require either stoicheiometric quantities of oxidising agent or require special catalysts.
We have developed a procedure for the oxidation of alkylated aromatic compounds that either partially or completely oxidises the alkyl group to an alcohol, aldehyde, ketone or carboxylic acid.
1
2 Thus, according to one aspect of the present invention,
3 there is provided a process for the oxidation of an
4 alkyl-aromatic compound, wherein the aromatic compound
5 is admixed with an oxidising agent or sulfur compound
6 in the presence of an ionic liquid. 7
8 In this process, air, dioxygen, peroxide, superoxide,
9 any other form of active oxygen, nitrite, nitrate, 0 nitric acid or other oxides (or oxyhalides) of nitrogen 1 (hydrated or anhydrous) are preferably used as the
12 oxidising agent. The process is usually under Bronsted
13 acidic conditions. 14
15 Preferably, the process involves ..the ..oxidation of- .the
16. -alkyl' side chain of .the. aromatic...compound in the'
171 presence of a nitrogen oxyacid species such as nitrate
18 or nitric acid. This nitrogen(V) species oxidises . the
19 alkyl group, and is in turn reduced to a lower valent 20 form of nitrogen. This lower valent form of nitrogen
21 can be re-oxidised back to nitrogen (V) by means of an
22 oxidising agent. Other oxidising agents suitable
23 include dioxygen (air), oxygen, peroxides, superoxides . 24
25 Other suitable oxidating agents are certain sulfur
26 compounds such as the sulfur acid/bases, eg H2S04 or
27 H2SO3. 28
29 This invention also allows for the separation of the
30 ionic liquid and product by physical or chemical means
31 such as distillation, steam distillation, azeotropic
32 distillation, sublimation, gravity separation, solvent
1 extraction, crystallisation, supercritical fluid
2 extraction and chromatography. 3
4 Ionic liquids consist of two components, which are a
5 positively charged cation and a negatively charged
6 anion. Generally, any compound that meets the
7 criterion of being a salt (consisting of an anion and
8 cation) and is fluid at or near the reaction
9 temperature or exists in a fluid state during any stage 10 of the reaction may be defined as an ionic liquid. 11
12 The cation for the present process is preferably a 1,
13 3-dialkylimidazolium cation such as l-methyl-3-
14 butylimidazoliu . Other cations for this process are 15. ammonium, pyrazolium, and other pyridinium,. alkyl- : or
16 poly-alkyIpyridinium, alkyl-, or poly-alkyl ..phosphonium
17 cations. 18.
19 The anion for the process is preferably a sulfur-
20 containing anion, such as sulfate, hydrogensulfate .
21 Non-sulfur containing anions include those based on
22 nitrogen, phosphorus, boron, silicon, selenium,
23 tellurium, halogens, oxoanions of metals, and organic
24 anions, such as trifluoroacetate, acetate, and anions
25 that are arsenic, antimony, and bismuth based. The
26 preferred anions are nitrate or methanesulfonate. 27
28 More than one ionic liquid or any combination of ionic
29 liquids can be used in the present invention.
30 Suitable Process conditions.
31 Temperature: ideally 100-120°C but to include 0° to
32 250°C
Pressure: ideally, atmospheric, but include 1 mbar to 100 bar
Time: ideally 24-48 hours, can be 1 minute to 1 month.
The reaction preferably requires an acid to be present. This acid is generally an oxoacid of nitrogen, sulfur, selenium, tellurium, phosphorus, arsenic, antimony, or an organic acid anion (e.g. acetate, trifluoroacetate) .
The oxidation of toluene is shown in scheme.!.'" As can be seen, the reaction can be carried out in [bmim] [OMs] ("OMs" = methanesύlfonate) by the addition of nitric acid or in [bmim] [N03] by the addition of methanesulfonic acid.
Scheme 1. The oxidation of toluene to benzoic acid.
As the reaction proceeds, the nitrate or nitric acid (the oxidising agent) is believed to be reduced to nitrous acid, which is unstable under the acidic conditions employed in the reaction. This in turn is re-oxidised back to nitrate/nitric acid by an oxidising agent. The
dioxygen in air will suffice, but other oxidants such as peroxides are also suitable.
The reaction can be carried out using a stoichiometric amount of nitric acid (or nitrate) or can be performed catalytically. In the latter case, if air is used to re-oxidise the nitrous acid formed in the reaction, the overall reaction is shown in scheme 2.
Scheme 2: The overall reaction for the oxidation . of toluene in air.
Other compounds oxidizable by this invention are. o- or.'■ p-xylene, firstly to o- or p-toluic acid (2- or 4- methylbenzoic acid) then to phthalic acid or terphthalic acids respectively. Ethylbenzene and n- propylbenzene can be oxidized under similar conditions to acetophenone and propiophenone as the major products. Also formed in these two reactions are benzoic acid, presumably from oxidative cleavage of the alkyl group.
The present invention is further illustrated with reference to the following Examples :
Examples :
1. Oxidation of toluene in [bmim] [OMs] In a round-bottomed flask (25cm3) equipped with a magnetic stirrer flea and reflux condenser, 1-butyl- 3-methylimidazolium methanesulfonate (0.23g, 1 mmol) and toluene (0.18g, 2 mmol) were added. 67% aqueous nitric acid (0.28g, 3 mmol) was cautiously added and the mixture heated under reflux for 48 hours. The flask was cooled arid the products analysed, by gas chromatography. All of the toluene had reacted and' signals due to benzoic acid (70 % yield) and a by- product (2- and 4-nitrotoluene) were detected. The product (s) was isolated by Kugelrohr distillation at 5 mm Hg. This gave pale yellow oil (bp = ,' IQOPCat 5 mmHg) nitrotoluene and a colourless solid -(bp •= ,150° ' at 5 mmHg) - benzoic acid. The structures were confirmed by NMR analysis and were in accordance: with authentic material.
2. Oxidation of toluene in [bmim] [OMs] In a round-bottomed flask (25cm3) equipped with a magnetic stirrer flea and reflux condensed, 1-butyl- 3-methylimidazolium methanesulfonate (0.23g, 1 mmol) and toluene (0.46g, 5 mmol) were added. 67% aqueous nitric acid (O.lδg, 2 mmol) was cautiously added and the mixture heated under reflux for 48 hours. The flask was cooled and the products analysed by gas chromatography. All of the toluene had reacted and signals due to benzoic acid (90% yield) and a by-
product (2- and 4-nitrotoluene) were detected. The product (s) was isolated by Kugelrohr distillation at 5 mmHg. This gave pale yellow oil (bp = 100°C at 5 mmHg) nitrotoluene and a colourless solid (bp = 150° at 5 mmHg) - benzoic acid. The structures were confirmed by N R analysis and were in accordance with authentic material .
3. Oxidation of toluene in [bmim] [N03] In a round-bottomed flask (25cm3) equipped with a magnetic stirrer flea and reflux condensed, 1-butyl- 3-methylimidazolium nitrate (0.23g, 2*,mmol) and toluene (0.46g, 5 mmol) were added. 67% methanesulfonic acid (0.29g, 3 mmol) was cautiously added, and the mixture heated under . reflux for 48 hours,. The flask was cooled and the products . analysed by gas chromatography^. ' All of the toluene • had reacted and signals due to benzoic acid .,(85% yield) and a by-product (2- and 4-nitrotoluene) were detected. The product (s) was isolated by Kugelrohr distillation at 5 mmHg. This gave pale yellow oil (bp = 100°C at 5 mmHg) nitrotoluene and a colourless solid (bp = 150° at 5 mmHg) - benzoic acid. The structures were confirmed by NMR analysis and were in accordance with authentic material.
4. Oxidation of ethylbenzene In a 50 cm3 round bottomed flask, equipped with a magnetic stirrer and reflux condenser, was added ethylbenzene (1.06 g, 10 mmol) and [bmim] [OMs] (1.0 g) . 67 % Nitric acid (0.45 g, 5 mmol) was cautiously added and the mixture heated under
1 reflux. After 48 hours the mixture was analysed by
2 gas chromatography and found to contain 19 %
3 unreacted ethylbenzene, 23 % benzoic acid and 57 %
4 acetophenone . The mixture was cooled and water (50
5 cm3) was added. The products were extracted with
6 diethyl ether (4 x 20 cm3) , concentrated on a rotary
7 evaporator and purified by Kugelrohr distillation.
8 This gave acetophenone (.0.62 g, 51 %) and benzoic
9 acid (0.22 g, 18 %) . 10
11. 5. Oxidation of p-xylene-
.12 In a 50 cm3 round bottomed flask., equipped with a
13 magnetic stirrer and reflux condenser, was added p-
14 xylene (1.07 g, 10 mmol) and [bmim] [OMs] (2.0 g) . .15' 67 % Nitric acid (0.9.0 g, 10 mmol) ' was cautiously
.16 added and the mixture ;heated under reflux.. After 2.4..
'.17: hours the mixture was :analysed by gas chromatography"'
18 (approximately 50 % conversion), cooled and water
19 (50 cm3) was added. The resultant precipitate was
20 collected by filtration and purified by vacuum
21 sublimation on a Kugelrohr apparatus. This gave two
22 crystalline solids, that were identified as 4-
23 methylbenzoic acid (0.50 g, 37 %) and benzene-1, 4-
24 dioic acid (terephthalic acid) (0.08 g, 5 %) . The
25 remainder was unreacted p-xylene. 26
27 The aqueous filtrate containing the ionic liquid was
28 concentrated, on a rotary evaporator (80°C at 50
29 mmHg) and transferred to the 50 cm3 round bottomed
30 flask, equipped with a magnetic stirrer and reflux
31 condenser. p-Xylene (5.35g, 50 mmol) and 67% nitric
32 acid (0.90 g, 10 mmol) was added. The mixture was
1 heated under reflux for 5 days, then cooled to room
2 temperature. During this time some of the p-xylene
3 was lost through evaporation. Dilution with water,
4 filtration and sublimation (as above) gave 4-
5 methylbenzoic acid (1.63 g, 24 %) and benzene-1,4-
6 dioic acid (terephthalic acid) (0.24 g, 3 %) . The
7 remainder was unreacted p-xylene . 8
9 6. Oxidation of o-xylene 0 In a 50 cm3 round bottomed flask, equipped with a 1 magnetic stirrer and reflux condenser, was: .,added o-
12 xylene (1.07 g, 10 mmol) arid [bmim] [OMs] (1.0 g) .
13 67 % Nitric acid (0.45 g, 5 mmol) was cautiously
14 added and the mixture heated under reflux. After 40
15 hours the mixture was analysed by .gas chromatography
16 and. gave..42 % conversion to 2-methylbenzoic acid -and . 17. trace of' phthalic a:cid. The remainder "Jj&as..'unreacted . 18 o-xylene.
19
20
21 7. Oxidation of propylbenzene
22
23 In a 50 cm3 round bottomed flask, equipped with a
24 magnetic stirrer and reflux condenser, was added
25 propylbenzene (1.21 g, 10 mmol) and [bmim] [OMs] (1.0
26 g) . 67 % Nitric acid (0.45 g, 5 mmol) was
27 cautiously added and the mixture heated under
28 reflux. After 54, 80 hours the mixture was analysed
29 by gas chromatography and found to give 15 %
30 conversion. Three products were identified (GCMS)
31 as: propiophenone, benzoic acid and 3-phenylpentane
32 in the ratio (2 : 1 : trace) .
In particular, the present invention relates to a process whereby aromatic compounds bearing an alkyl substituent are oxidised on the alkyl chain on the carbon atom next to the aromatic ring, and where the oxidation is performed in an ionic liquid.
The product of the oxidation reaction is preferably a carboxylic acid or ketone or an intermediate compound in the oxidation such as an aldehyde, or alcohol.
The oxidation is preferably performed in an ionic liquid containing an acid promoter such as methanesulfonic acid.
.The oxidation is preferably performed in an -ionic liquid containing ' nitrogen acid or salt such as nitric acid, nitrous acid, nitrate or nitrite salt-. The ionic liquid/acidic promoter combination can be used as a catalyst for the oxidation.
The ionic liquid/acidic promoter can be re-oxidised by an oxidising agent (such as dioxygen in air) , and the ionic liquid/acidic promoter can be recycled and reused in further reactions.
The ionic liquid/acidic promoter can be separated from the product by some physical or chemical means such as distillation, steam distillation, azeotropic distillation, sublimation, gravity separation, solvent extraction, crystallisation, supercritical fluid extraction and chromatography.
The present invention also extends to the use of an ionic liquid in the oxidation of an alkyl-aromatic compound, as well as an oxidised alkyl-aromatic compound whenever prepared by a process of the present invention.
References
[1] Hay, A. S.; Blanchard, H. S. Can. J. Che . , 1965, 43, 1306 [2] Ichikawa, Y. ; Yamashita, G.;' Tokashiki, M'. ; - Yamaji, T. Ind. Eng. Chem., 1070,62,38. [3] Yamazaki, S. Orgr.letfc., 1999,1,2129. t ] Higashijima, M. Chem.. -Lett. 1999, 1.093 [-] Sasson,,,. Y. ; Zappi, "G...D.; Neumann, R.-,.~ j ^ -Org. Chem-.. 1986, 51, 2.8.80
Claims (1)
- 1 Claims 23 1. A process for the oxidation of an alkyl-4 aromatic compound, wherein the aromatic5 compound is admixed with an oxidising agent or6 sulfur compound in the presence of an ionic7 liquid. 89 2. A process as claimed in Claim 1 wherein the10 oxidising agent is one or more of the group11 comprising: air, dioxygen, peroxide,12 . superoxide, any other form of active oxygen,13 nitrite, nitrate, . nitric acid or -other oxides'14 (or oxyhalides) of nitrogen (hydrated or15 anhydrous) and sulfur acid/base&. such as ,16\ sulfuric acid or sulfonic acid. ■1718 3. A process as claimed i Claim 1 or .Claim 219 wherein the process is' carried out under20 Bronsted acidic conditions. 2122 4. A process as claimed in any one of the23 preceding Claims involving the oxidation of the24 alkyl sidechain of the aromatic compound in the25 presence of a nitrogen oxyacid species. 2627 5. A process as claimed in Claim 4 wherein the28 nitrogen oxyacid species is a nitrate or nitric29 acid. 3031 6. A process as claimed in any one of the32 preceding Claims wherein the ionic liquid and reaction products can be separated by means of one or more of the following processes comprising: distillation, steam distillation, azeotropic distillation, sublimation, gravity separation, solvent extraction, crystallisation, supercritical fluid extraction and chromatography.7. A process as claimed in any one of the preceding Claims wherein the cation of the ionic liquid is one or more of the group comprising: ammonium, pyrazolium, 1,3- dialkylimidazolium, pyridinium, alkyl- or poly- alkyIpyridinium, alkyl- or poly-alkyl .phosphonium.8. A process as claimed ϊn Claim 7 wherein cation is a 1, 3-dialkylimidazolium cation such as 1- methyl-3-butylimidazolium.9. A process as claimed in any one of the preceding Claims wherein the anion of the ionic liquid is one or more of the group comprising: a sulfur-containing anion, such as sulfate, hydrogensulfate, non-sulfur-containing anions including those based on nitrogen, phosphorus, boron, silicon, selenium, tellurium, halogens, oxoanions of metals, and organic anions, such as trifluoroacetate, acetate, and anions that are arsenic, antimony, and bismuth-based.1 10. A process as claimed in Claim 9 wherein the2 anion is nitrate or methanesulfonate. 34 11. A process as claimed in any one of the5 preceding Claims wherein more than one ionic6 liquid or any combination of ionic liquids is7 used. 89 12. A process as claimed in any one of the 0 preceding Claims wherein an acid is present.1112 13. A process as claimed in Claim 12 wherein the-13 acid is one or more of the group comprising: an14 oxoacid of nitrogen, sulfur, selenium,15. tellurium, phosphorus, arsenic, -antimony, or an.16 organic acid anion (e.g. acetate or • 17 -. • trifluoro.acetate.) . 1819 14. A process as claimed in claim 13. wherein the20 acid is one or more of the following group21 comprising: methanesulfonic acid, nitric acid,.22 nitrous acid, nitrate or a nitrate salt. 2324 15. A process as claimed in any one of Claims 12 to25 14 wherein the ionic liquid/acid combination 26 also acts as a catalyst for the oxidation. 2728 16. A process as claimed in any one of Claims 12 to29 15 wherein the acid can be re-oxidised by an30 oxidising agent such as dioxygen in air. 311 17. A process as claimed in any one the preceding2 Claims wherein the ionic liquid is [bmin] [OMs]3 and the oxidising agent is nitric acid. 45 18. A process as claimed in any one of Claims 1 to6 16 wherein the ionic liquid is [bmin] [N03] and7 the oxidising agent is methanesulfonic acid. 89 19. A process as claimed in any one of the10 preceding Claims for the oxidation of11. alkylaromatics, toluene, xylene, or a benzene. ■1213 2,0. A process as claimed in Claim .19 for the14 oxidation of p-xylene. 1516 21. A. process as claimed ϊn any one of..the17 preceding Claims wherein the alkyl chain on .the'.18 carbon atom next to the aromatic ring is19 oxidised. 2021 22. A process as claimed in any one of the22 preceding Claims for the preparation of an23 aldehyde or alcohol. 2425 23. Use of an ionic liquid in a process as claimed26 in any one of Claims 1 to 22. 2728 24. Use of an ionic liquid in the oxidation of29 alkylaromatics, toluene, xylene or a benzene. 3025. An oxidated alkyl-aromatic compound obtainable by a process as defined in any one of Claims 1 to 22.26. A compound as claimed in Claim 25 wherein the alkyl aromatic starting compound is an alkylaroma'tic, toluene, xylene or a benzene.27. A process substantially as hereindescribed and with reference to the Exam les.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0024745 | 2000-10-10 | ||
| GBGB0024745.2A GB0024745D0 (en) | 2000-10-10 | 2000-10-10 | Oxidation of alkyl-aromatic compounds |
| PCT/GB2001/004426 WO2002030862A1 (en) | 2000-10-10 | 2001-10-05 | Oxidation of alkyl-aromatic compounds |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| AU2001293968A1 true AU2001293968A1 (en) | 2002-04-22 |
Family
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|---|---|---|---|
| AU2001293968A Abandoned AU2001293968A1 (en) | 2000-10-10 | 2001-10-05 | Oxidation of alkyl-aromatic compounds |
Country Status (10)
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|---|---|
| US (1) | US7094925B2 (en) |
| EP (1) | EP1324968A1 (en) |
| JP (1) | JP4334867B2 (en) |
| KR (1) | KR20040016813A (en) |
| CN (1) | CN1469856A (en) |
| AU (1) | AU2001293968A1 (en) |
| CA (1) | CA2425272A1 (en) |
| GB (1) | GB0024745D0 (en) |
| MX (1) | MXPA03003186A (en) |
| WO (1) | WO2002030862A1 (en) |
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| GB0112093D0 (en) * | 2001-05-18 | 2001-07-11 | Univ Belfast | Hydrogenation processes |
| DE10313207A1 (en) * | 2003-03-25 | 2004-10-07 | Basf Ag | Cleaning or processing ionic liquids with adsorptive separation processes |
| US7550627B2 (en) * | 2005-03-08 | 2009-06-23 | Eastman Chemical Company | Processes for producing aromatic dicarboxylic acids |
| US20060205974A1 (en) * | 2005-03-08 | 2006-09-14 | Lavoie Gino G | Processes for producing aromatic dicarboxylic acids |
| GB2427192A (en) * | 2005-06-17 | 2006-12-20 | Johnson Matthey Plc | A process for the oxidation of an alkyl-group containing substrate in the presence of an ionic liquid |
| KR100843594B1 (en) * | 2005-09-07 | 2008-07-03 | 주식회사 엘지화학 | Preparation of organic acids from aldehyde compounds by means of liquid phase oxidation reaction |
| US20070129568A1 (en) * | 2005-12-06 | 2007-06-07 | Ngimat, Co. | Ionic liquids |
| EP2125686B1 (en) * | 2006-12-21 | 2017-03-08 | Saudi Basic Industries Corporation | Process for preparing aromatic polycarboxylic acid by liquid phase oxidation |
| US8309760B2 (en) * | 2007-05-31 | 2012-11-13 | University Of Alabama | Process for purification of aryl carboxylic acids |
| TWI404700B (en) * | 2007-12-25 | 2013-08-11 | Saudi Basic Ind Corp | Process for preparing aromatic polycarboxylic acid by liquid phase oxidation |
| CN102115353B (en) * | 2009-12-30 | 2014-11-26 | 中国科学院大连化学物理研究所 | Method for selective oxidization of aromatic hydrocarbons |
| US8835678B2 (en) | 2010-06-30 | 2014-09-16 | Uop Llc | Solid terephthalic acid composition |
| US8884054B2 (en) * | 2010-06-30 | 2014-11-11 | Uop Llc | Process for oxidizing alkyl aromatic compounds |
| US8933266B2 (en) | 2010-06-30 | 2015-01-13 | Uop Llc | Process for producing terephthalic acid |
| US8754254B2 (en) | 2010-06-30 | 2014-06-17 | Uop Llc | Process for purifying terephthalic acid |
| US8933265B2 (en) * | 2010-06-30 | 2015-01-13 | Uop Llc | Process for oxidizing alkyl aromatic compounds |
| US8884055B2 (en) * | 2010-06-30 | 2014-11-11 | Uop Llc | Process for producing terephthalic acid |
| US9045407B2 (en) * | 2010-06-30 | 2015-06-02 | Uop Llc | Mixtures used in oxidizing alkyl aromatic compounds |
| US9024059B2 (en) * | 2011-12-29 | 2015-05-05 | Uop Llc | Process for producing terephthalic acid |
| US8759571B2 (en) * | 2011-12-29 | 2014-06-24 | Uop Llc | Process for oxidizing alkyl-aromatic compounds |
| US9156765B2 (en) | 2011-12-29 | 2015-10-13 | Uop Llc | Process for oxidizing alkyl-aromatic compounds |
| US8927764B2 (en) * | 2011-12-29 | 2015-01-06 | Uop Llc | Process for producing terephthalic acid |
| CN104011005A (en) * | 2011-12-29 | 2014-08-27 | 环球油品公司 | Process for producing terephthalic acid |
| US8946471B2 (en) | 2011-12-29 | 2015-02-03 | Uop Llc | Process for oxidizing an alkyl-aromatic compound |
| US20130172609A1 (en) * | 2011-12-29 | 2013-07-04 | Uop Llc | Process for oxidizing an alkyl-aromatic compound |
| US9085522B2 (en) | 2011-12-29 | 2015-07-21 | Uop Llc | Process for producing terephthalic acid |
| EP2735820A1 (en) * | 2012-11-21 | 2014-05-28 | Evonik Industries AG | Absorption heat pump, and absorption agent for an absorption heat pump comprising methanesulfonic acid |
| US9233905B2 (en) * | 2012-12-14 | 2016-01-12 | Uop Llc | Oxidation and crystallization process for aromatic carboxylic acid production |
| MX2015015105A (en) | 2013-04-30 | 2016-06-07 | Reliance Ind Ltd | A composition for preparing terephthalic acid. |
| US9150485B2 (en) | 2013-10-08 | 2015-10-06 | Uop Llc | Process for controlling reaction and crystallization solvent composition in process for production of aromatic carboxylic acid |
| MX2016010862A (en) * | 2014-02-20 | 2017-12-07 | Reliance Industries Ltd | A catalyst recovery and recycling process during aromatic carboxylic acid production. |
| CN105175692B (en) * | 2015-10-21 | 2017-05-10 | 浙江海洋学院 | High-performance resin material synthesized on basis of PX (p-xylene) |
| CN105254653A (en) * | 2015-10-21 | 2016-01-20 | 浙江海洋学院 | PX based inorganic super-molecular substance synthesis and preparation method |
| CN110655458B (en) * | 2018-06-29 | 2022-07-12 | 中国石油化工股份有限公司 | Method for simultaneously producing benzoic acid and acetone |
| CN115448830A (en) * | 2021-06-09 | 2022-12-09 | 复旦大学 | Method for promoting oxidation of compound containing saturated carbon-hydrogen bond by light |
| CN113956148B (en) * | 2021-10-29 | 2022-12-16 | 南京工业大学 | Acid/photocatalysis oxidation reaction of carbon-hydrogen bond at benzyl position of aromatic compound |
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|---|---|---|---|---|
| US3124611A (en) * | 1964-03-10 | Oxidation of aromatic compounds | ||
| US2993070A (en) * | 1959-04-06 | 1961-07-18 | Degussa | Process for the production of terephthalic acid |
| US3310581A (en) * | 1964-03-02 | 1967-03-21 | Joseph R Mares | Oxidation of alkyl-substituted aromatic compounds |
| GB9319945D0 (en) * | 1993-09-28 | 1993-11-17 | Solvay Interox Ltd | Oxidation of alkylaromatic compounds |
| AU2165000A (en) | 1998-12-04 | 2000-06-19 | Symyx Technologies, Inc. | Combinatorial discovery and testing of ionic liquids |
| DE19901524A1 (en) * | 1999-01-16 | 2000-07-20 | Wilhelm Keim | Catalyst stabilization in distillation of products from homogeneous catalysis, e.g. hydroformylation, hydrogenation or oxidation, uses ionic liquid containing quaternary ammonium and/or phosphonium cation |
-
2000
- 2000-10-10 GB GBGB0024745.2A patent/GB0024745D0/en not_active Ceased
-
2001
- 2001-10-05 MX MXPA03003186A patent/MXPA03003186A/en unknown
- 2001-10-05 EP EP01974453A patent/EP1324968A1/en not_active Ceased
- 2001-10-05 WO PCT/GB2001/004426 patent/WO2002030862A1/en active Search and Examination
- 2001-10-05 JP JP2002534252A patent/JP4334867B2/en not_active Expired - Fee Related
- 2001-10-05 KR KR10-2003-7005003A patent/KR20040016813A/en not_active Application Discontinuation
- 2001-10-05 CA CA002425272A patent/CA2425272A1/en not_active Abandoned
- 2001-10-05 AU AU2001293968A patent/AU2001293968A1/en not_active Abandoned
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| JP2004523477A (en) | 2004-08-05 |
| CA2425272A1 (en) | 2002-04-18 |
| WO2002030862A1 (en) | 2002-04-18 |
| JP4334867B2 (en) | 2009-09-30 |
| EP1324968A1 (en) | 2003-07-09 |
| GB0024745D0 (en) | 2000-11-22 |
| US7094925B2 (en) | 2006-08-22 |
| KR20040016813A (en) | 2004-02-25 |
| US20040015009A1 (en) | 2004-01-22 |
| CN1469856A (en) | 2004-01-21 |
| MXPA03003186A (en) | 2004-12-06 |
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