CN112094258B - Method for preparing naphthopyran compounds based on alkynyl-substituted aza-p-methylene benzoquinone - Google Patents
Method for preparing naphthopyran compounds based on alkynyl-substituted aza-p-methylene benzoquinone Download PDFInfo
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Abstract
The invention discloses a method for preparing naphthopyran compounds based on alkynyl-substituted aza-p-methylene benzoquinone, which comprises the following steps: adding a 4-amino aryl substituted propargyl alcohol compound, a 2-naphthol compound, a catalyst and a solvent into a reaction container, and synthesizing the naphthopyran compound at room temperature. The synthesis method has the advantages of convenient operation, high yield, no need of oxidant, cheap and easily obtained synthesis raw materials and wide application range of functional groups. Except for the final product, the intermediates in a series of conversion processes of the invention do not need to be separated and purified, a simple, high-efficiency and low-cost preparation method is provided for the naphthopyran compounds, and the naphthopyran compounds have good practical value for the process development of naphthopyran products and downstream products thereof.
Description
Technical Field
The invention belongs to the technical field of organic synthesis, and particularly relates to a method for preparing naphthopyran compounds based on alkynyl-substituted aza-p-methylene benzoquinone.
Background
The naphthopyran skeleton structure is widely existed in natural products and medicine molecules. The main method for synthesizing the skeleton structure at present is that propargyl alcohol and 2-naphthol are subjected to cyclization reaction under the conditions of metal catalyst and high temperature: (1) zhang, h.; wang, k.; wang, b.; yi, h.; hu, f.; li, C.; zhang y.; wang, j.rhodium (III) -catalyst transport of Cyclopropenes with N-phenoxyamides through C-H activation. angelw.chem.int.ed.2014, 53,13234 (2) Arai, k.; kobayashia, y.; abe, J.random molecular designs for dry access of the color-plated spots of photoresist and primers. chem.Commun.2015,51,3057. However, the above method has various problems such as difficult operation, uneconomical or unavailable catalyst, large functional group limitation, low product yield, long reaction time, and the like.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide a method for preparing naphthopyran compounds based on alkynyl-substituted aza-p-methylene benzoquinone. The method has the advantages of simple operation, cheap and easily obtained raw materials, wide application range of functional groups and high yield
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the method for preparing the naphthopyran compounds based on the alkynyl-substituted aza-p-methylene benzoquinone comprises the following steps: adding a 4-amino aryl substituted propargyl alcohol compound, a 2-naphthol compound, a catalyst and a solvent into a reaction container, and synthesizing the naphthopyran compound at room temperature, wherein the reaction formula is shown as the following formula:
in the formula:
(1) PG is arylsulfonyl, alkylsulfonyl, arylacyl or alkylacyl;
(2) r is phenyl or monosubstituted phenyl, and the substituent is halogen, alkyl, alkoxy or trifluoromethyl which is independently substituted at each position of ortho, meta or para of a benzene ring;
(3)R 1 is phenyl or monosubstituted phenyl, and the substituent is ortho, meta or para of benzene ringHalogen, alkyl or alkoxy independently substituted at each position;
(4)R 2 is hydrogen atom, halogen, alkyl, alkoxy or trifluoromethyl.
Preferably, the time of the synthesis reaction is 3.5-36 h.
Preferably, the catalyst is selected from one of (+/-) -camphorsulfonic acid, p-toluenesulfonic acid, trifluoroacetic acid, (+/-) -binaphthol phosphate and diphenyl phosphate. More preferably, the catalyst is (+ -) -binaphthol phosphate, and the reaction is more efficient using the catalyst.
Preferably, the solvent is selected from one of dichloromethane, 1, 2-dichloroethane, ethyl acetate, tetrahydrofuran, toluene and acetonitrile. More preferably, the solvent is dichloromethane, and the reaction is more efficient using this solvent.
Preferably, in the synthesis method, the molar ratio of the 4-amino aryl substituted propargyl alcohol compound to the 2-naphthol compound is 1: 1, the mol ratio of the 2, 4-amino aryl substituted propargyl alcohol compound to the catalyst is 1: (0.02-0.2), and the using amount of the solvent is 1 mol/L.
The propargyl alcohol compound is an organic compound which is convenient and easy to obtain, amino and alkynyl in the structure of the propargyl alcohol compound can flexibly carry out the transformation of various functional groups, and the property of bifunctional groups enables the propargyl alcohol compound to carry out a series of serial cyclization reactions.
Under the catalytic action of a protonic acid catalyst, the 4-amino aryl substituted propargyl alcohol compound and the 2-naphthol compound can be subjected to 1, 8-conjugate addition/intramolecular 6-endo cyclization to synthesize the naphthopyran compound at room temperature.
Compared with the prior art, the invention has the following beneficial effects: the naphthopyran compound can be synthesized from the 4-amino aryl substituted propargyl alcohol compound and the 2-naphthol compound by a one-pot method at room temperature. The synthesis method has the advantages of convenient operation, high yield, no need of oxidant, cheap and easily obtained synthesis raw materials and wide application range of functional groups. Except for the final product, the intermediates in a series of conversion processes of the invention do not need to be separated and purified, a simple, high-efficiency and low-cost preparation method is provided for the naphthopyran compounds, and the method has good practical value for the process development of the naphthopyran products and downstream products thereof.
Drawings
FIG. 1 shows the product synthesized in example 1 1 H NMR spectrum;
FIG. 2 shows the synthesis of the product of example 1 13 C NMR spectrum;
FIG. 3 shows the product synthesized in example 2 1 H NMR spectrum;
FIG. 4 shows the synthesis of the product of example 2 13 C NMR spectrum;
FIG. 5 shows the synthesis of the product of example 3 1 H NMR spectrum;
FIG. 6 shows the synthesis of example 3 13 C NMR spectrum;
FIG. 7 shows the synthesis of the product of example 4 1 H NMR spectrum;
FIG. 8 shows the synthesis of the product of example 4 13 C NMR spectrogram;
FIG. 9 shows the product synthesized in example 5 1 H NMR spectrum;
FIG. 10 shows the synthesis of example 5 13 C NMR spectrum;
FIG. 11 shows the synthesis of the product of example 6 1 H NMR spectrum;
FIG. 12 shows the synthesis of example 6 13 C NMR spectrum.
Detailed Description
The technical solutions of the present invention will be further described with reference to the following examples, and it should be understood that the described examples are only a part of the examples of the present invention, and not all of the examples. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The starting materials used in the examples are commercially available and the procedures used are conventional in the art unless otherwise specified.
Example 1
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (76.6mg,0.2mmol), 2-naphthol (34.6mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were sequentially added to a 15mL conventional reaction tube, and the reaction system was left at room temperature for reaction for 5 hours. The reaction system was directly subjected to silica gel (200-300 mesh) column chromatography (mobile phase component petroleum ether: ethyl acetate: 5:1) to separate and obtain a light red solid product (109mg, yield: 99%).
The product detection data are as follows: 1 H NMR(500MHz,CDCl 3 )δ7.68(d,J=8.9Hz,1H),7.64(d,J=8.1Hz,1H),7.50(t,J=8.4Hz,4H),7.44–7.39(m,2H),7.37–7.13(m,12H),7.07(d,J=8.9Hz,1H),7.01–6.95(m,1H),6.16(s,1H),1.24ppm(s,9H).
13 C NMR(126MHz,CDCl 3 )δ176.5,152.5,144.6,141.2,139.9,137.3,137.2,130.8,130.2,129.7,129.2,128.4,128.3,128.01,127.95,127.9,127.6,127.4,126.9,126.4,125.0,123.1,119.3,118.7,116.6,81.9,39.5,27.5ppm.
example 2
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (90.2mg, 0.2mmol), 2-naphthol (34.6mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were sequentially added to a 15mL conventional reaction tube, and the reaction system was left at room temperature for reaction for 14 h. The reaction system was directly subjected to silica gel (200-300 mesh) column chromatography (mobile phase component petroleum ether: ethyl acetate: 5:1) to separate and obtain a light red solid product (111.9mg, yield: 97%).
The product detection data are as follows: 1 H NMR(500MHz,CDCl 3 )δ7.71(d,J=8.8Hz,1H),7.66(d,J=8.0Hz,1H),7.59(d,J=8.2Hz,2H),7.53–7.38(m,8H),7.32(d,J=8.8Hz,1H),7.30–7.14(m,5H),7.02(ddd,J=8.1,6.8,1.2Hz,1H),6.96(d,J=8.5Hz,1H),6.20(s,1H),1.23ppm(s,9H).
13 C NMR(126MHz,CDCl 3 )δ176.5,152.6,144.7,144.2,139.4,137.4,136.2,131.2,130.5,130.2,129.8,129.5,129.3,128.5,128.2,128.1,127.8,127.6,126.9,126.1,125.4,125.2,123.3,123.1,119.4,118.7,115.9,81.9,39.5,27.5ppm.
example 3
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (72.6mg,0.2mmol), 2-naphthol (34.6mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were sequentially added to a 15mL conventional reaction tube, and the reaction system was left at room temperature for reaction for 6 h. The reaction system is directly subjected to silica gel (200-300 meshes) column chromatography (the mobile phase component is petroleum ether: ethyl acetate: 5:1) to separate a light red solid product (78.2mg, yield: 80%).
The product test data are as follows: 1 H NMR(500MHz,CDCl 3 )δ8.05(d,J=8.6Hz,1H),7.67(d,J=7.7Hz,1H),7.60(d,J=8.8Hz,1H),7.51–7.32(m,7H),7.23(ddt,J=17.2,14.6,7.2Hz,6H),6.00(s,1H),2.91(dtt,J=22.6,15.1,7.6Hz,2H),1.55–1.44(m,2H),1.34(dq,J=14.4,7.4Hz,2H),1.23(s,9H),0.85ppm(t,J=7.3Hz,3H).
13 C NMR(126MHz,CDCl 3 )δ176.4,151.9,145.0,140.4,137.0,136.3,130.17(t,J=13.3Hz),128.8,127.9(d,J=4.0Hz),127.2,126.9(d,J=12.3Hz),125.8,124.9,123.1,119.3,118.8,118.2,81.7,39.5,35.1,31.3,27.5,22.4,13.9ppm.
example 4
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (80.6mg,0.2mmol), 2-naphthol (34.6mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were sequentially added to a 15mL conventional reaction tube, and the reaction system was left at room temperature for reaction for 4 h. The reaction system was directly subjected to silica gel (200-300 mesh) column chromatography (mobile phase component petroleum ether: ethyl acetate: 5:1) to separate and obtain a light red solid product (100.5mg, yield: 95%).
The product test data are as follows: 1 H NMR(500MHz,CDCl 3 )δ7.84(s,1H),7.77–7.59(m,4H),7.48(ddd,J=30.8,15.1,7.3Hz,7H),7.39–7.04(m,14H),6.98(t,J=7.6Hz,1H),6.17ppm(s,1H).
13 C NMR(126MHz,CDCl 3 )δ165.7,152.5,144.4,141.1,140.3,137.3,137.2,134.8,131.7,130.8,130.2,129.7,129.2,128.7,128.4,128.3,128.0,127.9,127.6,127.5,127.0,126.9,126.4,125.1,123.2,119.7,118.7,116.6,81.9ppm.IR:3475,3363,2921,2855,1655,1461,1385,1185,1138,1074,698cm -1 .
example 5
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (90.6mg,0.2mmol), 2-naphthol (34.6mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were sequentially added to a 15mL conventional reaction tube, and the reaction system was left at room temperature for reaction for 7 h. The reaction system was directly subjected to silica gel (200-300 mesh) column chromatography (mobile phase component petroleum ether: ethyl acetate: 5:1) to separate and obtain a light red solid product (81.1mg, yield: 70%).
The product test data are as follows: 1 H NMR(500MHz,DMSO)δ10.24(s,1H),7.84(d,J=8.9Hz,1H),7.77(d,J=8.1Hz,1H),7.57–7.49(m,4H),7.44(t,J=9.5Hz,3H),7.39–7.23(m,7H),7.22–7.13(m,4H),7.05–6.97(m,3H),6.92(d,J=8.6Hz,1H),6.33(s,1H),2.24ppm(s,3H).
13 C NMR(126MHz,DMSO)δ152.0,144.1,143.2,140.4,139.6,137.1,136.7,136.2,131.0,129.9,129.6,128.9,128.6,128.1,127.8,127.7,127.4,127.3,126.5,126.3,125.5,125.3,123.4,119.4,118.8,116.1,81.1,20.9ppm.
example 6
The synthesis of the naphthopyran compound comprises the following steps:
a stirrer, propargyl alcohol aniline compound (76.6mg,0.2mmol), 7-bromo-2-naphthol (53.0mg,0.24mmol), (+ -) -binaphthol phosphate (1.4mg,0.004mmol) and methylene chloride (2mL) were added in this order to a 15mL conventional reaction tube, and the reaction system was left to react at room temperature for 3 hours. The reaction system was directly subjected to silica gel (200-300 mesh) column chromatography (mobile phase component petroleum ether: ethyl acetate: 5:1) to separate and obtain a light red solid product (113.9mg, yield: 97%).
The product detection data are as follows: 1 H NMR(500MHz,CDCl 3 )δ7.77(d,J=2.0Hz,1H),7.56(d,J=8.8Hz,1H),7.52–7.45(m,4H),7.41(d,J=8.8Hz,2H),7.30(ddd,J=26.4,11.5,5.5Hz,9H),7.23–7.16(m,2H),7.03(dd,J=9.2,2.0Hz,1H),6.93(d,J=9.2Hz,1H),6.17(s,1H),1.22ppm(s,9H).
13 C NMR(126MHz,CDCl 3 )δ176.5,152.6,144.2,140.7,139.5,137.3,136.8,131.4,130.1,129.8,129.6,128.6,128.2,128.1,128.02,127.99,127.84,127.82,127.5,126.9,119.7,119.4,116.9,116.8,82.0,39.5,27.5ppm.
finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (6)
1. The method for preparing the naphthopyran compounds based on the alkynyl-substituted aza-p-methylene benzoquinone is characterized by comprising the following steps of: adding the compound 1, the compound 2, a catalyst and a solvent into a reaction vessel, and synthesizing the naphthopyran compound shown as the compound 3 at room temperature, wherein the reaction formula is shown as the following formula:
in the formula:
(1) PG is arylsulfonyl, alkylsulfonyl, arylacyl or alkylacyl;
(2) r is phenyl or monosubstituted phenyl, and the substituent is halogen, alkyl, alkoxy or trifluoromethyl independently substituted at each position in ortho-position, meta-position and para-position of a benzene ring;
(3)R 1 is phenyl or monosubstituted phenyl, and the substituent is halogen, alkyl or alkoxy independently substituted at each position of ortho, meta or para of a benzene ring;
(4)R 2 is hydrogen atom, halogen, alkyl, alkoxy or trifluoromethyl;
the catalyst is (+/-) -binaphthol phosphate.
2. The method of claim 1, wherein the synthesis reaction time is 3.5 to 36 hours.
3. The method of claim 1, wherein the solvent is selected from one of dichloromethane, 1, 2-dichloroethane, ethyl acetate, tetrahydrofuran, toluene, and acetonitrile.
4. The method of claim 1, wherein the solvent is dichloromethane.
5. The method of claim 1, wherein the molar ratio of compound 1 to compound 2 is 1: 1.2.
6. the method of claim 1, wherein the compound 1 to catalyst molar ratio is 1: (0.02-0.2).
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Convenient synthesis of naphthopyrans using montmorillonite K-10 as heterogeneous catalyst;RAHMAN HOSSEINZADEH et al.,;《 J.Chem.Sci.》;20141231;第126卷(第4期);第1085页Scheme3和第1086页表2,第1083页 2.3部分,第1088页表6 * |
Synthesis of Naphthopyrans via Formal (3+3)-Annulation of Propargylic (Aza)-para-Quinone Methides with Naphthols;Xiang-Zhi Zhang et al.,;《J.Org.Chem.》;20200929;第85卷;第13306−13316页 * |
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