CN112979551B - Synthesis method of pyrazolone containing quaternary carbon atoms - Google Patents
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- CN112979551B CN112979551B CN202110281682.8A CN202110281682A CN112979551B CN 112979551 B CN112979551 B CN 112979551B CN 202110281682 A CN202110281682 A CN 202110281682A CN 112979551 B CN112979551 B CN 112979551B
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- pyrazolone
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- quaternary carbon
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- 125000004432 carbon atom Chemical group C* 0.000 title claims abstract description 25
- JEXVQSWXXUJEMA-UHFFFAOYSA-N pyrazol-3-one Chemical compound O=C1C=CN=N1 JEXVQSWXXUJEMA-UHFFFAOYSA-N 0.000 title claims abstract description 25
- 238000001308 synthesis method Methods 0.000 title claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 16
- XJHCXCQVJFPJIK-UHFFFAOYSA-M caesium fluoride Chemical compound [F-].[Cs+] XJHCXCQVJFPJIK-UHFFFAOYSA-M 0.000 claims abstract description 14
- XBHPFCIWRHJDCP-UHFFFAOYSA-N (2-trimethylsilylphenyl) trifluoromethanesulfonate Chemical compound C[Si](C)(C)C1=CC=CC=C1OS(=O)(=O)C(F)(F)F XBHPFCIWRHJDCP-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000002904 solvent Substances 0.000 claims abstract description 13
- QELUYTUMUWHWMC-UHFFFAOYSA-N edaravone Chemical compound O=C1CC(C)=NN1C1=CC=CC=C1 QELUYTUMUWHWMC-UHFFFAOYSA-N 0.000 claims abstract description 11
- XEZNGIUYQVAUSS-UHFFFAOYSA-N 18-crown-6 Chemical compound C1COCCOCCOCCOCCOCCO1 XEZNGIUYQVAUSS-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000003444 phase transfer catalyst Substances 0.000 claims abstract description 5
- 238000010438 heat treatment Methods 0.000 claims abstract description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 18
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical group CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 15
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 12
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 9
- 239000003208 petroleum Substances 0.000 claims description 6
- 238000000926 separation method Methods 0.000 claims description 6
- 239000012043 crude product Substances 0.000 claims description 5
- 238000004440 column chromatography Methods 0.000 claims description 4
- 238000000746 purification Methods 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 238000010189 synthetic method Methods 0.000 claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical class [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 3
- 230000006837 decompression Effects 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 3
- 239000012074 organic phase Substances 0.000 claims description 3
- 239000000843 powder Substances 0.000 claims description 3
- 239000000741 silica gel Substances 0.000 claims description 3
- 229910002027 silica gel Inorganic materials 0.000 claims description 3
- 239000003513 alkali Substances 0.000 claims description 2
- 239000003480 eluent Substances 0.000 claims description 2
- 239000003054 catalyst Substances 0.000 abstract description 5
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 229910000510 noble metal Inorganic materials 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 229910052723 transition metal Inorganic materials 0.000 abstract description 3
- 150000003624 transition metals Chemical class 0.000 abstract description 3
- 238000005580 one pot reaction Methods 0.000 abstract description 2
- -1 lactam heterocyclic compounds Chemical class 0.000 description 14
- 238000005481 NMR spectroscopy Methods 0.000 description 6
- UHOVQNZJYSORNB-UHFFFAOYSA-N monobenzene Natural products C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- UXFHZGKRWAEYAM-UHFFFAOYSA-N 5-methyl-2,4-diphenyl-4h-pyrazol-3-one Chemical compound CC1=NN(C=2C=CC=CC=2)C(=O)C1C1=CC=CC=C1 UXFHZGKRWAEYAM-UHFFFAOYSA-N 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 4
- 230000000269 nucleophilic effect Effects 0.000 description 4
- 150000001345 alkine derivatives Chemical class 0.000 description 3
- 150000001721 carbon Chemical group 0.000 description 3
- 239000002585 base Substances 0.000 description 2
- 230000004071 biological effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 125000000325 methylidene group Chemical group [H]C([H])=* 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- KLYCPFXDDDMZNQ-UHFFFAOYSA-N Benzyne Chemical compound C1=CC#CC=C1 KLYCPFXDDDMZNQ-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000000202 analgesic effect Effects 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 230000001754 anti-pyretic effect Effects 0.000 description 1
- 230000002365 anti-tubercular Effects 0.000 description 1
- 239000003472 antidiabetic agent Substances 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 239000002221 antipyretic Substances 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 150000002391 heterocyclic compounds Chemical class 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229940126904 hypoglycaemic agent Drugs 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229930014626 natural product Natural products 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000012265 solid product Substances 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D231/00—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings
- C07D231/02—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings
- C07D231/10—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D231/14—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D231/18—One oxygen or sulfur atom
- C07D231/20—One oxygen atom attached in position 3 or 5
- C07D231/22—One oxygen atom attached in position 3 or 5 with aryl radicals attached to ring nitrogen atoms
- C07D231/26—1-Phenyl-3-methyl-5- pyrazolones, unsubstituted or substituted on the phenyl ring
Abstract
The invention provides a synthesis method of pyrazolone containing quaternary carbon atoms, which comprises the steps of taking cesium fluoride as a base and 18-crown-6-ether as a phase transfer catalyst, heating 3-methyl-1-phenyl-5-pyrazolone and 2- (trimethylsilyl) phenyl trifluoro methane sulfonate in a solvent for reaction, separating and purifying to obtain pyrazolone containing quaternary carbon atoms. Compared with the prior art, the invention realizes the synthesis reaction without an external metal catalyst through the one-pot reaction. The reaction overcomes the need of adding transition metal or noble metal catalyst in the prior reaction, and provides a new way for developing pyrazolone compounds containing quaternary carbon atoms.
Description
Technical Field
The invention belongs to the field of organic compounds, and particularly relates to a synthesis method of pyrazolone containing quaternary carbon atoms.
Background
The pyrazolone compounds are five-membered lactam heterocyclic compounds containing 4 substitutable positions, the derivatives obtained by substituting different positions with substituent groups are parent nucleus structures of a plurality of natural products and medicines, and the pyrazolone compounds have wide antibacterial and biological activities, can be used as antipyretic, analgesic, antituberculosis, hypoglycemic agents, antibacterial agents and the like, and have good development prospects especially in the pesticide field. In addition, certain pyrazolone compounds have remarkable functions in terms of coordination performance as an extractant, and can also be used as an analytical reagent, an antioxidant, a photosensitive material, a dye and the like. Certain pyrazolone compounds also have better photochromic properties in the solid state and are used in printing, sunglasses and cosmetics.
As an important heterocyclic compound, in recent years, chemists have synthesized a number of pyrazolone compounds having excellent bioactivity through metal catalysis or splice design. In view of the good biological activity of the compounds, the search for a synthetic method of the compounds has very important practical significance.
Disclosure of Invention
The invention aims to provide a synthesis method of pyrazolone containing quaternary carbon atoms, which has the advantages of simple preparation method, mild condition and no need of additional transition metal or noble metal catalyst, and provides a new way for developing pyrazolone compounds containing quaternary carbon atoms.
The specific technical scheme of the invention is as follows:
a synthesis method of pyrazolone containing quaternary carbon atoms, which comprises the following steps:
cesium fluoride is used as a base, 18-crown-6-ether is used as a phase transfer catalyst, 3-methyl-1-phenyl-5-pyrazolone and 2- (trimethylsilyl) phenyl trifluoro methane sulfonate are heated in a solvent for reaction, and the pyrazolone containing quaternary carbon atoms can be prepared after separation and purification.
The heating reaction is carried out at 70 ℃ for 12-15 h.
The chemical structural formula of the 3-methyl-1-phenyl-5-pyrazolone is as follows:
the chemical structural formula of the 2- (trimethylsilyl) phenyl trifluoro methane sulfonate is as follows:
the solvent is acetonitrile or toluene;
further, the mass ratio of 3-methyl-1-phenyl-5-pyrazolone, 2- (trimethylsilyl) phenyl trifluoromethane sulfonate, 18-crown-6-ether and cesium fluoride is 1:2.2:2:2;
the concentration of the 2- (trimethylsilyl) phenyl trifluoro methane sulfonate in the solvent is 0.4-0.6mol/L.
The structural formula of the 18-crown-6-ether is as follows:
the separation and purification method comprises the following steps: after the reaction, the crude product is extracted and separated by ethyl acetate and saturated saline, an organic phase is collected, silica gel powder is added, and after decompression and spin drying, the volume ratio is 1: ethyl acetate 60-80: and (3) carrying out column chromatography separation by using petroleum ether as an eluent, and then recrystallizing and purifying by using petroleum ether as a solvent.
The synthesized pyrazolone containing quaternary carbon atoms has the structural formula:
the reaction mechanism of the invention is as follows: acetonitrile or toluene is used as a solvent, 2- (trimethylsilyl) phenyl trifluoro methane sulfonate generates a benzene alkyne intermediate under the induction of fluoride ions, methylene in 3-methyl-1-phenyl-5-pyrazolone nucleophilic attack the benzene alkyne intermediate under alkaline conditions, and hydrogen atoms are transferred, so that 3-methyl-1, 4-diphenyl-5-pyrazolone is generated by reaction; and C4 in the 3-methyl-1, 4-diphenyl-5-pyrazolone again nucleophilic attack alkyne intermediate, and hydrogen atoms are transferred to react to generate a pyrazolone compound containing quaternary carbon atoms, namely the 3-methyl-1, 4-triphenyl-5-pyrazolone. The mechanism diagram is shown in fig. 5.
Compared with the prior art, the invention provides a synthesis method of a pyrazolone compound containing quaternary carbon atoms, which uses 2- (trimethylsilicon) phenyl trifluoro methane sulfonate as a benzene alkyne precursor, cesium fluoride as alkali and 18-crown-6-ether as a phase transfer catalyst, and realizes the reaction with 3-methyl-1-phenyl-5-pyrazolone under the condition of no additional metal catalyst through a one-pot reaction. The reaction overcomes the need of adding transition metal or noble metal catalyst in the prior reaction, and provides a new way for developing pyrazolone compounds containing quaternary carbon atoms.
Drawings
FIG. 1 is a schematic representation of the structure of a pyrazolone compound containing quaternary carbon atoms prepared in example 1;
FIG. 2 is a synthetic route for a pyrazolone compound containing a quaternary carbon atom prepared in example 1;
FIG. 3 is a nuclear magnetic resonance hydrogen spectrum of a pyrazolone compound containing a quaternary carbon atom prepared in example 1;
FIG. 4 is a nuclear magnetic resonance carbon spectrum of a pyrazolone compound having a quaternary carbon atom prepared in example 1;
FIG. 5 is a diagram showing the mechanism of the synthesis of the present invention.
Detailed Description
Example 1
A method for synthesizing pyrazolone containing quaternary carbon atoms, which comprises the following steps:
reacting 1.0mmol of 3-methyl-1-phenyl-5-pyrazolone and 2.2mmol of 2- (trimethylsilyl) phenyl trifluoro methane sulfonate with 2.0mmol of cesium fluoride as a base and 2.0mmol of 18-crown-6-ether as a phase transfer catalyst in 5mL of acetonitrile solvent for 12 hours at 70 ℃ to obtain a crude product of the pyrazolone containing quaternary carbon atoms; the prepared crude product of pyrazolone containing quaternary carbon atoms is extracted by saturated saline water and ethyl acetate, an organic phase is collected, silica gel powder is added, and after decompression spin-drying, the crude product is prepared by using ethyl acetate with the volume ratio: petroleum ether = 1: and (3) separating by 60 column chromatography, and recrystallizing and purifying by using petroleum ether as a solvent to obtain a white solid product, namely the pyrazolone compound containing quaternary carbon atoms, wherein the yield of the column chromatography is about 70%.
Wherein, the purity of the 3-methyl-1-phenyl-5-pyrazolone is more than 98.0 percent (T), TCL company; 2- (trimethylsilyl) phenyl triflate, purity >95%, TCI company.
The synthesized pyrazolone containing quaternary carbon atoms has the structural formula:
the product obtained in example 1 was structured by 1 H NMR、 13 C NMR was performed as follows:
1 H NMR(400MHz,CDCl 3 )δ8.02(d,J＝8.0Hz,2H),δ7.45-7.36(m,8H),δ7.28-7.20(m,5H),δ2.19(s,3H)；
13 C NMR(125MHz,CDCl 3 )δ173.6,161.8,138.1,137.3,128.5,128.2,125.2,118.9,69.0,15.5。
the reaction mechanism is shown in figure 5, acetonitrile is taken as a solvent, and the 2- (trimethylsilyl) phenyl trifluoro methane sulfonate b generates a benzyne intermediate c under the induction of fluoride ions. Nucleophilic attack of methylene in 3-methyl-1-phenyl-5-pyrazolone a on alkyne intermediate c under alkaline condition, hydrogen atom transfer, and reaction to generate 3-methyl-1, 4-diphenyl-5-pyrazolone d; and C4 in the 3-methyl-1, 4-diphenyl-5-pyrazolone d is nucleophilic and attacks the alkyne intermediate c again, and hydrogen atoms are transferred, so that a pyrazolone compound containing quaternary carbon atoms is generated, namely the 3-methyl-1, 4-triphenyl-5-pyrazolone e.
The above detailed description of the synthesis of pyrazolone compounds containing quaternary carbon atoms with reference to examples is illustrative and not limiting, and several examples can be listed according to the defined scope, thus falling within the scope of protection of the present invention without departing from the general concept of the invention.
Claims (4)
1. A synthesis method of pyrazolone containing quaternary carbon atoms, which is characterized by comprising the following steps:
cesium fluoride is used as alkali, 18-crown-6-ether is used as a phase transfer catalyst, 3-methyl-1-phenyl-5-pyrazolone and 2- (trimethylsilyl) phenyl trifluoro methane sulfonate are heated in a solvent for reaction, and the pyrazolone containing quaternary carbon atoms can be prepared after separation and purification;
the chemical structural formula of the 2- (trimethylsilyl) phenyl trifluoro methane sulfonate is as follows:；
the heating reaction is carried out for 12-15 hours at 70 ℃;
the ratio of the amounts of the substances of 3-methyl-1-phenyl-5-pyrazolone, 2- (trimethylsilyl) phenyl trifluoromethane sulfonate, 18-crown-6-ether and cesium fluoride is 1:2.2:2:2;
the synthesized pyrazolone containing quaternary carbon atoms has the structural formula:。
2. the synthetic method of claim 1 wherein the solvent is acetonitrile or toluene.
3. The synthetic method according to claim 1 or 2, characterized in that the concentration of the 2- (trimethylsilyl) phenyltrifluoromethane sulfonate in the solvent is 0.4-0.6mol/L.
4. The synthetic method according to claim 1 or 2, wherein the separation and purification method is as follows: after the reaction, the crude product is extracted and separated by ethyl acetate and saturated saline, an organic phase is collected, silica gel powder is added, and after decompression and spin drying, the volume ratio is 1: ethyl acetate 60-80: and (3) carrying out column chromatography separation by using petroleum ether as an eluent, and then recrystallizing and purifying by using petroleum ether as a solvent.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111662339A (en) * | 2020-06-28 | 2020-09-15 | 安徽师范大学 | Ferrocenyl-containing arylamine compound and synthesis method thereof |
| CN111675591A (en) * | 2020-06-28 | 2020-09-18 | 安徽师范大学 | Synthetic method of benzophenanthrene compound |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111662339A (en) * | 2020-06-28 | 2020-09-15 | 安徽师范大学 | Ferrocenyl-containing arylamine compound and synthesis method thereof |
| CN111675591A (en) * | 2020-06-28 | 2020-09-18 | 安徽师范大学 | Synthetic method of benzophenanthrene compound |
Non-Patent Citations (3)
| Title |
|---|
| Metal- and Oxidant-Free Modular Approach To Access N‑Alkoxy Oxindoles via Aryne Annulation;Ritesh Singh et al.;《Organic Letters》;第20卷;第4848−4853页 * |
| Metal-free one-pot sequential direct diarylation of pyrazolin-5-ones with diaryliodonium salts;Tao Huang et al.;《The Royal Society of Chemistry》;第5卷;第66598–66601页 * |
| Reaction of arynes with amino acid esters;Kentaro Okuma et al.;《Chem. Commun.》;第47卷;第5822–5824页 * |
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