CN101486694B - The preparation method of 2,5-dimethylfuran-3,4-diethyl carboxylate - Google Patents
The preparation method of 2,5-dimethylfuran-3,4-diethyl carboxylate Download PDFInfo
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- CN101486694B CN101486694B CN200910103287XA CN200910103287A CN101486694B CN 101486694 B CN101486694 B CN 101486694B CN 200910103287X A CN200910103287X A CN 200910103287XA CN 200910103287 A CN200910103287 A CN 200910103287A CN 101486694 B CN101486694 B CN 101486694B
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- dimethyl furan
- dicarboxylate
- dimethylfuran
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- 238000002360 preparation method Methods 0.000 title claims description 11
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 36
- 238000006243 chemical reaction Methods 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 239000000126 substance Substances 0.000 claims description 5
- 239000003153 chemical reaction reagent Substances 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 4
- 239000003960 organic solvent Substances 0.000 abstract description 4
- 231100000331 toxic Toxicity 0.000 abstract description 4
- 230000002588 toxic effect Effects 0.000 abstract description 4
- IDYRARBMMCSVMD-UHFFFAOYSA-N 2,5-dimethylfuran-3,4-dicarboxylic acid Chemical compound CC=1OC(C)=C(C(O)=O)C=1C(O)=O IDYRARBMMCSVMD-UHFFFAOYSA-N 0.000 abstract 1
- GJEDSIHWCPPJFN-UHFFFAOYSA-N diethyl 2,3-diacetylbutanedioate Chemical compound CCOC(=O)C(C(C)=O)C(C(C)=O)C(=O)OCC GJEDSIHWCPPJFN-UHFFFAOYSA-N 0.000 abstract 1
- AXFRLGGVPMYNMU-UHFFFAOYSA-N diethyl 2,5-dimethylfuran-3,4-dicarboxylate Chemical compound CCOC(=O)C1=C(C)OC(C)=C1C(=O)OCC AXFRLGGVPMYNMU-UHFFFAOYSA-N 0.000 abstract 1
- 238000009776 industrial production Methods 0.000 abstract 1
- 238000010992 reflux Methods 0.000 abstract 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 16
- IDYRARBMMCSVMD-UHFFFAOYSA-L 2,5-dimethylfuran-3,4-dicarboxylate Chemical compound CC=1OC(C)=C(C([O-])=O)C=1C([O-])=O IDYRARBMMCSVMD-UHFFFAOYSA-L 0.000 description 11
- 238000001644 13C nuclear magnetic resonance spectroscopy Methods 0.000 description 5
- 238000005160 1H NMR spectroscopy Methods 0.000 description 5
- 238000006086 Paal-Knorr synthesis reaction Methods 0.000 description 4
- 239000012230 colorless oil Substances 0.000 description 4
- 238000006210 cyclodehydration reaction Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- 239000000706 filtrate Substances 0.000 description 3
- 238000003818 flash chromatography Methods 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 229940079593 drug Drugs 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000012044 organic layer Substances 0.000 description 2
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000741 silica gel Substances 0.000 description 2
- 229910002027 silica gel Inorganic materials 0.000 description 2
- 229960001866 silicon dioxide Drugs 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- NDQXKKFRNOPRDW-UHFFFAOYSA-N 1,1,1-triethoxyethane Chemical compound CCOC(C)(OCC)OCC NDQXKKFRNOPRDW-UHFFFAOYSA-N 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- WRQNANDWMGAFTP-UHFFFAOYSA-N Methylacetoacetic acid Chemical compound COC(=O)CC(C)=O WRQNANDWMGAFTP-UHFFFAOYSA-N 0.000 description 1
- KEAYESYHFKHZAL-UHFFFAOYSA-N Sodium Chemical compound [Na] KEAYESYHFKHZAL-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000004071 biological effect Effects 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 238000006114 decarboxylation reaction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 150000002240 furans Chemical class 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hcl hcl Chemical compound Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229940031815 mycocide Drugs 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- JOXIMZWYDAKGHI-UHFFFAOYSA-N toluene-4-sulfonic acid Chemical compound CC1=CC=C(S(O)(=O)=O)C=C1 JOXIMZWYDAKGHI-UHFFFAOYSA-N 0.000 description 1
- 230000000699 topical effect Effects 0.000 description 1
- 239000003171 wood protecting agent Substances 0.000 description 1
Landscapes
- Furan Compounds (AREA)
Abstract
本发明公开了一种2，5-二甲基呋喃-3，4-二甲酸二乙酯的制备方法，由2，3-二乙酰琥珀酸二乙酯在浓度为0.1～1N的盐酸溶液中微波加热回流反应制得，具有不使用昂贵试剂或毒性有机溶剂、成本低廉、操作简单方便、适合工业化生产等优点；并且，通过调节盐酸溶液的浓度，还可以根据需要同时选择性获得2，5-二甲基呋喃-3-甲酸乙酯和/或2，5-二甲基呋喃-3，4-二甲酸；具有广阔、良好的应用前景。The invention discloses a method for preparing diethyl 2,5-dimethylfuran-3,4-dicarboxylate, which consists of diethyl 2,3-diacetylsuccinate in a hydrochloric acid solution with a concentration of 0.1-1N It is prepared by microwave heating and reflux reaction, which has the advantages of not using expensive reagents or toxic organic solvents, low cost, simple and convenient operation, and suitable for industrial production; moreover, by adjusting the concentration of hydrochloric acid solution, it can also selectively obtain 2,5 - Ethyl dimethylfuran-3-carboxylate and/or 2,5-dimethylfuran-3,4-dicarboxylic acid; it has broad and good application prospects.
Description
Technical field
The present invention relates to the preparation method of organic compound, particularly 2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate.
Background technology
Furane derivative is the pharmacophore unit of many chemical synthetic drugs and natural drug, also is the important intermediate in the organic synthesis.Wherein, trisubstituted furans---2, the derivative of 5-dimethyl furan-3-ethyl formate has multiple biological activity, can be used as wood preservative, sterilant, sterilant and mycocide (CN1152307A, 1997; JP 09255675A, 1997; DE 2323197,1973) etc.; Four substituted furans---2,5-dimethyl furan-3,4-dioctyl phthalate and 2,5-dimethyl furan-3,4-dicarboxylate are important chemical material and medicine intermediate (Press JB et al.Eur J Med Chem, 1989,24,627; Nowak I et al.J.Fluorine Chem, 1995,75,115; Gould KJ et al.J Chem Soc, Perkin Trans.1,1980,1834).
2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate, bibliographical information has multiple, as by 2,3-diacetyl ethyl succinate back flow reaction in the mixing solutions of the vitriol oil and tetracol phenixin makes, or by 2,3-diacetyl ethyl succinate makes with the perchloric acid processing in ethyl orthoacetate, or by 2,3-diacetyl ethyl succinate back flow reaction in the mixing solutions of tosic acid and benzene makes (Henry MF et al.J OrgChem, 1980,45,1699; Zhurnal Organicheskoi Khimii, 1996,32,891; Wu AX et al.JChem Res Synop, 1998,3,136).But existing, these methods use expensive reagent or toxic organic solvent, the more high problems of cost.
Summary of the invention
In view of this, for overcoming the deficiencies in the prior art, the object of the present invention is to provide a kind of 2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate does not use expensive reagent or toxic organic solvent, with low cost, simple to operation, be fit to suitability for industrialized production.
For reaching this purpose, the invention provides a kind of 2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate, by 2,3-diacetyl ethyl succinate is that the microwave heating back flow reaction makes in the hydrochloric acid soln of 0.1～1N in concentration, chemical equation is as follows:
Further, the concentration of described hydrochloric acid soln is 0.4N.
Beneficial effect of the present invention is: the invention discloses a kind of 2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate has advantages such as expensive reagent do not used or toxic organic solvent, with low cost, simple to operation, suitable suitability for industrialized production; And, by regulating the concentration of hydrochloric acid soln, selectivity acquisition simultaneously 2 as required, 5-dimethyl furan-3-ethyl formate and/or 2,5-dimethyl furan-3,4-dioctyl phthalate; Has wide, good prospects for application.
Embodiment
In order to make the purpose, technical solutions and advantages of the present invention clearer, below the preferred embodiments of the present invention are described in detail.
In a preferred embodiment, adopt MAS-II type normal pressure microwave synthetic/that the extractive reaction workstation carries out microwave is synthetic, adopt tlc (GF254 silica-gel plate) monitoring reaction process, flash column chromatography (200～300 order silica gel) purification of target product, gained target product adopt the X-4 micro-fusing point instrument of type (digital display) to measure fusing point (mp), Bruker AV-300 type nmr determination
1H NMR (300MHz) and
13C NMR (75MHz) (TMS is interior mark).
Raw material 2,3-diacetyl ethyl succinate is according to literature method (Fan Nengting, the organic synthesis topical reference book. Beijing: press of Beijing Institute of Technology, 1992,804) be prepared: in two mouthfuls of round-bottomed flasks of 1L, add anhydrous diethyl ether (300mL) and cut the sodium Metal 99.5 (4.5g of oxide on surface, 0.2mol), silicone oil bubbler (in the release reaction with the hydrogen that produces) is installed, under agitation condition, slowly drip methyl aceto acetate (26.0g, 0.2mol), dropwise back stirring at room reaction 24 hours, under agitation condition, slowly drip again and contain I
2(25.0g, anhydrous diethyl ether 0.1mol) (75mL) dropwise the back and continue stirring reaction 4 hours to reaction solution and fade, filter, filtrate is reclaimed solvent, resistates acetic acid recrystallization, make 2,3-diacetyl ethyl succinate (white crystal 17.0g, yield 66%);
1H NMR (CDCl
3) δ: 4.48 (1H, s), 4.16 (2H, q, J=7.1Hz), 2.41 (3H, s), 1.26 (3H, t, J=7.1Hz);
13C NMR (CDCl
3) δ: 201.6,167.2,62.2,58.0,30.9,14.1.
Discover, with 2,3-diacetyl ethyl succinate (I) is a raw material, adopts the inventive method preparation 2,5-dimethyl furan-3, during 4-dicarboxylate (IV),, can selectivity obtain two kinds of reaction product (details sees Table 1) by regulating the concentration of hydrochloric acid (HCl) solution, be respectively: (1) 2,5-dimethyl furan-3-ethyl formate (II) and 2,5-dimethyl furan-3, the mixture of 4-dicarboxylate (IV); (2) 2,5-dimethyl furan-3-ethyl formate (II), 2,5-dimethyl furan-3,4-dioctyl phthalate (III) and 2,5-dimethyl furan-3, the mixture of 4-dicarboxylate (IV); Chemical equation is as follows:
Table 1, HCl strength of solution and product yield
As shown in Table 1, when the HCl strength of solution is 0.1～0.4N, reaction product is 2,5-dimethyl furan-3-ethyl formate (II) and 2,5-dimethyl furan-3, the mixture of 4-dicarboxylate (IV), and 2,5-dimethyl furan-3, the yield of 4-dicarboxylate (IV) fluctuates along with the concentration of HCl solution, reaches maximum (61%) during for 0.4N in the HCl strength of solution; When the HCl strength of solution continued to increase to 1N, reaction product became 2,5-dimethyl furan-3-ethyl formate (II), 2,5-dimethyl furan-3,4-dioctyl phthalate (III) and 2,5-dimethyl furan-3, the mixture of 4-dicarboxylate (IV).
The contriver thinks, the reason that causes above-mentioned phenomenon may be: 2,3-diacetyl ethyl succinate (I) can generate 2 through decarboxylation and the reaction of Paal-Knorr cyclodehydration, 5-dimethyl furan-3-ethyl formate (II), also can directly generate 2 through the reaction of Paal-Knorr cyclodehydration, 5-dimethyl furan-3,4-dicarboxylate (IV), the yield of product II or IV depends primarily on the speed of decarboxylic reaction and the reaction of Paal-Knorr cyclodehydration, the HCl solution of high density can quicken the reaction of Paal-Knorr cyclodehydration, when its speed of response during faster than decarboxylic reaction, then 2,3-diacetyl ethyl succinate (I) is dehydrated into ring and forms stable conjugated system with carbonyl, stops the generation of decarboxylic reaction subsequently; 2,5-dimethyl furan-3, hydrolysis reaction can take place and generate 2 in 4-dicarboxylate (IV) in HCl solution, 5-dimethyl furan-3,4-dioctyl phthalate (III), and hydrolysis rate increases along with the HCl strength of solution and accelerates, so only when the HCl strength of solution is hanged down, just can obtain 2,5-dimethyl furan-3,4-dicarboxylate (IV).
Embodiment one
Take by weighing 2,3-diacetyl ethyl succinate (I) (243mg, 0.94mmol), (concentration is 0.4N to add HCl solution, 3.3mL), normal pressure microwave heating back flow reaction 2 hours is cooled to room temperature, extracted with diethyl ether, collected organic layer, water and salt water washing successively, anhydrous sodium sulfate drying filters, filtrate is reclaimed solvent, resistates makes 2 respectively, 5-dimethyl furan-3-ethyl formate (II) (colorless oil 51mg through flash column chromatography [with sherwood oil-ether (5: 1) wash-out] purifying, yield 21%) and 2,5-dimethyl furan-3,4-dicarboxylate (IV) (colorless oil 138mg, yield 61%).
2,5-dimethyl furan-3-ethyl formate (II):
1H NMR (CDCl
3) δ: 1.33 (t, 3H, J=7.1Hz), 2.36 (s, 3H), 2.52 (s, 3H), 4.26 (q, 2H, J=7.1Hz), 6.21 (s, 1H);
13C NMR (CDCl
3) δ: 13.2,13.7,14.5,60.0,106.3,114.2,150.0,157.6,164.4; Consistent with bibliographical information (Wang Y et al.Org Lett, 2005,7,925).
2,5-dimethyl furan-3,4-dicarboxylate (IV):
1H NMR (CDCl
3) δ: 1.30 (t, 2 * 3H, J=7.1Hz), 2.43 (s, 2 * 3H), 4.29 (q, 2 * 2H, J=7.1 Hz);
13C NMR (CDCl
3) δ: 13.0,13.8,60.5,113.6,155.5,163.5; Consistent with bibliographical information (Bellur E et al.Tetrahedron Lett, 2005,46,2185).
Embodiment two
Take by weighing 2,3-diacetyl ethyl succinate (I) (184.7mg, 0.72mmol), (concentration is 1N to add HCl solution, 1.2mL), normal pressure microwave heating back flow reaction 1 hour is cooled to room temperature, extracted with diethyl ether, collected organic layer, water and salt water washing successively, anhydrous sodium sulfate drying filters, filtrate is reclaimed solvent, resistates makes 2 respectively with flash column chromatography [with sherwood oil-ether (5: 1) wash-out, using the ether wash-out again] purifying, 5-dimethyl furan-3-ethyl formate (II) (colorless oil 24.0mg, yield 20%), 2,5-dimethyl furan-3,4-dioctyl phthalate (III) (white crystal 36.6mg, yield 24%) and 2,5-dimethyl furan-3,4-dicarboxylate (IV) (colorless oil 90.0mg, yield 52%).
2,5-dimethyl furan-3,214～216 ° of 4-dioctyl phthalate (III): mp;
1H NMR (CD
3COCD
3) δ: 2.60 (s, 2 * 3H);
13C NMR (CD
3COCD
3) δ: 14.5,112.4,161.5,166.6; Consistent with the determination data of commercial goods.
Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although by invention has been described with reference to the preferred embodiments of the present invention, but those of ordinary skill in the art is to be understood that, can make various changes to it in the form and details, and the spirit and scope of the present invention that do not depart from appended claims and limited.
Claims (2)
1.2,5-dimethyl furan-3, the preparation method of 4-dicarboxylate is characterized in that: by 2,3-diacetyl ethyl succinate is that the microwave heating back flow reaction makes in the hydrochloric acid of 0.1～1N in concentration, and chemical equation is as follows:
2. according to claim 12,5-dimethyl furan-3, the preparation method of 4-dicarboxylate is characterized in that: the concentration of described hydrochloric acid is 0.4N.
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| CN101863881A (en) * | 2010-06-21 | 2010-10-20 | 扬州大学 | Synthetic method of multi-substituted furan drug molecules |
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