CN110981790B - 1,4-dihydropyridine derivative and synthetic method thereof - Google Patents
1,4-dihydropyridine derivative and synthetic method thereof Download PDFInfo
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Abstract
The invention provides a 1,4-dihydropyridine derivative and a synthesis method thereof, wherein the synthesis steps of a 1,4-dihydropyridine derivative are as follows: firstly, adding an alkaline catalyst, a solvent, an additive and a reducing agent into a reaction bottle to react in the atmosphere of carbon dioxide gas; and secondly, adding an enamine compound and an acidic catalyst into the reaction system in the first step, wherein the acidic catalyst is one or more selected from Lewis acid catalysts and Bronsted acid catalysts, and performing cyclization reaction to obtain the 1,4-dihydropyridine derivative. The synthesis method of the invention uses carbon dioxide as C1 to synthesize the building block, and has the characteristics of renewable raw materials, environmental friendliness and good substrate universality.
Description
Technical Field
The invention belongs to the field of organic compound synthesis, and particularly relates to a 1,4-dihydropyridine derivative and a synthesis method thereof.
Background
1,4-dihydropyridine derivatives are important nitrogen-containing heterocyclic compounds, and are molecules which are of great interest in the fields of pharmaceutical chemistry and organic synthetic chemistry. The molecules have the activities of resisting HIV, bacteria, convulsion, tumor, neuroprotection, radiation protection and the like. 1,4-dihydropyridine structure is also widely present in cardiovascular and hypotensive drugs. The early synthesis method of the compound is mainly realized by Hantzsch reaction (1,3-dicarbonyl compound, aldehyde and amine or ammonium salt three-component condensation reaction). Later, a 1,4-dihydropyridine synthesis based on aminoenones was developed, for example: (a) Yang, j. -y.; wang, C. -Y.; xie, x.; li, H. -F.; li, y, z.eur.j.org.chem.2010,4189; (b) Wan, j. -p.; zhou, r. -h.; liu, y. -y.; cai, m. -z.rsc adv.2013,3,2477; (c) Wan, j. -p.; gan, s. -f.; sun, g. -l.; pan, y. -j.j.org.chem.2009,74,2862; (d) Al-Awadi, n.a.; ibrahim, m.r.; elnagdi, m.h.; john, e.; ibrahim, y.a. beilstein j.org.chem.2012,8,441; (e) Zheng, r. -l.; zeng, X. -X.; he, h. -y.; he, j.; yang, S. -Y.; yu, l. -t.; yang, l.synth.commun.2012,42,1521; (f) Wan, j. -p.; liu, y.rsc adv.2012,2,9763; (g) Wan, j. -p.; wang, C. -P.; tetrahedron 2011,67,922; (h) Churchill, g.h.; raw, s.a.; powell, l.tetrahedron lett.2011,52,3657; (i) muthus avanann, s.; perumal, s.; almansour, a.i.tetrahedron lett.2012,53,1144.
However, a method for synthesizing 1,4-dihydropyridine derivatives using a green and renewable carbon source, carbon dioxide, as a synthetic raw material has yet to be developed.
Disclosure of Invention
The invention aims to provide a 1,4-dihydropyridine derivative and a synthesis method thereof, wherein carbon dioxide is used as a C1 synthesis building block, and the method has the characteristics of renewable raw materials, environmental friendliness and good substrate universality.
The invention provides a synthetic method of 1,4-dihydropyridine derivatives, which comprises the following synthetic steps: firstly, adding an alkaline catalyst, a solvent, an additive and a reducing agent into a reaction bottle to react in the atmosphere of carbon dioxide gas; secondly, adding an enamine compound and an acidic catalyst into the reaction system in the first step, wherein the acidic catalyst is selected from one or more of Lewis acid catalysts and Bronsted acid catalysts, and performing cyclization reaction to obtain 1,4-dihydropyridine derivatives in the formula (I); the reaction is shown as the formula (II):
in the formula (II), R 1 Is a ketocarbonyl or ester carbonyl substituent;
R 2 is an aryl substituent;
the acidic catalyst is a Lewis acid catalyst or a Bronsted acid catalyst.
Preferably, the additive is selected from one or more of secondary alkyl amine and primary alkyl amine.
Preferably, the additive is n-butylamine.
Preferably, the reducing agent is selected from one or more of phenylsilane and diphenylsilane.
Further, the reducing agent is phenylsilane.
Preferably, the basic catalyst is selected from one or more of 1,5,7-triazabicyclo (4.4.0) dec-5-ene (TBD), cesium carbonate and betaine.
Further, the basic catalyst is 1,5,7-triazabicyclo (4.4.0) dec-5-ene (TBD).
Preferably, the lewis acid catalyst is selected from zinc chloride, feCl 3 One or more of boron trifluoride diethyl etherate; the Bronsted acid catalyst is trifluoromethanesulfonic acid.
Further, the lewis acid catalyst is zinc chloride.
Preferably, the enamine compound: additive: carbon dioxide: reducing agent: basic catalyst: the molar ratio of the acidic catalyst is 1: (0.5-6): (1-4): (2-10): (0.1-0.5): (0.1-0.5).
Preferably, the solvent is selected from one or more of acetonitrile, N-dimethylformamide, 1,4-dioxane, 1,2-dichloroethane.
Further, the solvent is acetonitrile.
Preferably, the reaction temperature of the first step is 90-110 ℃ and the reaction temperature of the second step is 100-120 ℃.
Preferably, the reaction time of the first step is 6-12h, and the reaction time of the second step is 12-24h.
The invention also provides a 1,4-dihydropyridine derivative prepared by the synthesis method of 1,4-dihydropyridine derivative, which has a structure shown in formula (I):
in the formula (I), R 1 Is a ketocarbonyl or ester carbonyl substituent; r 2 Is an aryl substituent.
In one embodiment, the method for synthesizing 1,4-dihydropyridine derivatives of the present invention comprises: filling a 25 ml sealed tube with carbon dioxide gas, taking n-butylamine as an additive, taking phenylsilane as a reducing agent, taking TBD as a basic catalyst, adding acetonitrile, reacting at 100 ℃ for 6 hours, adding an enamine compound and a Lewis acid catalyst zinc chloride, reacting at 120 ℃ for 24 hours, detecting by TLC to complete reaction, and purifying to obtain the 1,4-dihydropyridine derivative shown in the formula (I).
Wherein the enamine compound: additive: carbon dioxide: reducing agent: basic catalyst: the molar ratio of the acidic catalyst is 1:4:4:4:0.3:0.3.
the 1,4-dihydropyridine derivative synthesized by the method is applied to the fields of synthesis and medicinal chemistry.
The invention has the beneficial effects that: the carbon dioxide is a renewable substance, the carbon dioxide is used as a carbon source raw material, the method is environment-friendly, and a new idea is provided for the effective reuse of carbon dioxide which is one of the main components of greenhouse gases. In addition, the enamine compound is simple and convenient to synthesize. Enamine compounds and carbon dioxide are used as raw materials, and the 1,4-dihydropyridine derivatives with excellent yield are obtained through a one-pot reaction under the action of additives, reducing agents, basic catalysts and acidic catalysts.
Detailed Description
The present invention will be further described in detail with reference to the following specific examples, but the present invention is not limited to the following examples. Variations and advantages that may occur to those skilled in the art are intended to be included within the invention without departing from the spirit and scope of the inventive concept, and the scope of the invention is to be determined by the appended claims. The procedures, conditions, reagents, experimental methods and the like for carrying out the present invention are general knowledge and common general knowledge in the art except for the contents specifically mentioned below, and the present invention is not particularly limited.
Example 1:
synthesis of 1-phenyl-3,5-dibenzoyl-1,4-dihydropyridine IA
The enamine compound, solvent, additive, reducing agent, basic catalyst and acidic catalyst are amine ketene, acetonitrile, n-butylamine, phenylsilane, TBD and zinc chloride respectively. The raw materials are simple and easy to obtain, a noble metal catalyst is not required, and the method is environment-friendly.
To a dry 25 ml pressure-tight tube, TBD (0.075 mmol) and carbon dioxide displacement gas were added three times. Acetonitrile (2 mL), phenylsilane (1 mol) and n-butylamine (1 mol) were added under carbon dioxide gas blanket to react at 115 ℃ for 6 hours. Cooling to 25 ℃, under the protection of carbon dioxide gas, continuously adding amine ketene (0.25 mol) and zinc chloride (0.075 mmol) into a sealed tube, and reacting at 120 ℃ for 24 hours to obtain the target product (IA) as a yellow solid, wherein the separation yield is 90%, and mp is 142-144 ℃.
Nuclear magnetic data of the product: 1 H NMR(500MHz,CDCl 3 ):δ7.63(d,J＝7.2Hz,4H),7.51-7.43(m,6H),7.37-7.34(m,2H),7.25-7.22(m,1H),7.17(s,2H),7.06(d,J＝7.8Hz,2H),3.65(s,2H)； 13 C{ 1 H}NMR(125MHz,CDCl 3 ):δ194.77,143.08,141.45,138.98,131.00,130.03,128.49,128.39,126.60,120.74,117.24,21.71。
product high resolution mass spectrometry data: HRMS (ESI) calcd for C 25 H 20 NO 2 [M+H] + :366.1489,found 366.1494.
Example 2:
synthesis of 1- (4-methoxyphenyl) -3,5-dibenzoyl-1,4-dihydropyridine IB
Enamine compound, solvent, additive, reducing agent, basic catalyst and acidic catalyst are p-methoxyaniline ketene amine, acetonitrile, n-butylamine, phenylsilane, TBD and zinc chloride. The raw materials are simple and easy to obtain, a noble metal catalyst is not required, and the method is environment-friendly.
To a dry 25 ml pressure-tight tube, TBD (0.075 mmol) and carbon dioxide displacement gas were added three times. Acetonitrile (2 mL), phenylsilane (1 mol), and n-butylamine (1 mol) were added under carbon dioxide gas blanket and reacted at 115 ℃ for 6 hours. Cooling to 25 ℃, under the protection of carbon dioxide gas, continuously adding p-anisidine amine ketene (0.25 mol) and zinc chloride (0.075 mmol) into a sealed tube, and reacting at 120 ℃ for 20 hours to obtain the target product (IB) which is a yellow solid, wherein the isolation yield is 89%, and mp is 166-168 ℃.
Nuclear magnetic data of the product: 1 H NMR(500MHz,CDCl 3 ):δ7.60(d,J＝7.1Hz,4H),7.49-7.47(m,2H),7.44-7.41(m,4H),7.06(s,2H),7.00(d,J＝8.9Hz,2H),6.86(d,J＝8.9Hz,2H),3.77(s,3H),3.64(s,2H)； 13 C{ 1 H}NMR(125MHz,CDCl 3 ):δ194.70,158.30,142.22,139.05,136.45,130.88,128.43,128.33,122.81,116.64,115.05,55.56,21.55。
product high resolution mass spectrometry data: HRMS (ESI) calcd for C 26 H 22 NO 3 [M+H] + :396.1594,found 396.1596.
Example 3:
synthesis of 1- (4-chlorophenyl) -3,5-dibenzoyl-1,4-dihydropyridine IC
Enamine compound, solvent, additive, reducing agent, basic catalyst and acidic catalyst are p-chloroaniline ketene, acetonitrile, n-butylamine, phenylsilane, TBD and zinc chloride. The raw materials are simple and easy to obtain, a noble metal catalyst is not required, and the method is environment-friendly.
To a dry 25 ml pressure-tight tube, TBD (0.075 mmol) and carbon dioxide displacement gas were added three times. Acetonitrile (2 mL), phenylsilane (1 mol) and n-butylamine (1 mol) were added under carbon dioxide gas blanket to react at 115 ℃ for 6 hours. Cooling to 25 ℃, under the protection of carbon dioxide gas, continuously adding parachloroaniline amine ketene (0.25 mol) and zinc chloride (0.075 mmol) into a sealed tube, and reacting at 120 ℃ for 24 hours to obtain a target product (IC) which is a yellow solid, wherein the isolation yield is 72 percent, and mp is 195-197 ℃.
Nuclear magnetic data of the product: 1 H NMR(500MHz,CDCl 3 ):δ7.61(d,J＝7.4Hz,4H),7.52-7.49(m,2H),7.46-7.43(m,4H),7.31(d,J＝8.5Hz,2H),7.10(s,2H),6.99(d,J＝8.6Hz,2H),3.63(s,2H)； 13 C{ 1 H}NMR(125MHz,CDCl 3 ):δ194.65,141.57,140.86,138.81,132.16,131.14,130.14,128.47,128.43,121.99,117.54,21.70。
product high resolution mass spectrometry data: HRMS (ESI) calcd for C 25 H 19 ClNO 2 [M+H] + :400.1099,found 400.1094.
Example 4:
synthesis of 1-phenyl-3,5-bis (4-chlorobenzoyl) -1,4-dihydropyridine ID
Enamine compounds, solvents, additives, reducing agents, basic catalysts and acidic catalysts are respectively selected from chloroaminoketene, acetonitrile, n-butylamine, phenylsilane, TBD and zinc chloride. The raw materials are simple and easy to obtain, a noble metal catalyst is not required, and the method is environment-friendly.
To a dry 25 ml pressure-tight tube, TBD (0.075 mmol) and carbon dioxide displacement gas were added three times. Acetonitrile (2 mL), phenylsilane (1 mol) and n-butylamine (1 mol) were added under carbon dioxide gas blanket to react at 115 ℃ for 6 hours. Cooling to 25 ℃, under the protection of carbon dioxide gas, continuously adding chloroaminoketene (0.25 mol) and zinc chloride (0.075 mmol) into a sealed tube, and reacting at 120 ℃ for 20 hours to obtain the target product (ID) which is a yellow solid, wherein the isolation yield is 89%, and mp is 145-147 ℃.
Nuclear magnetic data of the product: 1 H NMR(500MHz,CDCl 3 ):δ7.59-7.56(m,4H),7.49(d,J＝8.2Hz,2H),7.43-7.38(m,4H),7.28-7.26(m,1H),7.11(s,2H),7.06(d,J＝7.9Hz,2H),3.62(s,2H)； 13 C{ 1 H}NMR(125MHz,CDCl 3 ):δ196.65,158.61,137.21,135.63,132.95,129.65,129.45,128.72,128.31,128.10,124.80,15.7。
product high resolution mass spectrometry data: HRMS (ESI) calcd for C 25 H 18 Cl 2 NO 2 [M+H] + :434.0709,found 434.0702.
Example 5:
synthesis of 1-phenyl-3,5-bis (4-methoxybenzoyl) -1,4-dihydropyridine IE
Enamine compound, solvent, additive, reducing agent, basic catalyst and acidic catalyst are methoxy substituted amine ketene, acetonitrile, n-butylamine, phenylsilane, TBD and zinc chloride. The raw materials are simple and easy to obtain, a noble metal catalyst is not required, and the method is environment-friendly.
To a dry 25 ml pressure-tight tube, TBD (0.075 mmol) and carbon dioxide displacement gas were added three times. Acetonitrile (2 mL), phenylsilane (1 mol) and n-butylamine (1 mol) were added under carbon dioxide gas blanket to react at 115 ℃ for 6 hours. Cooling to 25 ℃, under the protection of carbon dioxide gas, continuously adding methoxy substituted amine ketene (0.25 mol) and zinc chloride (0.075 mmol) into a sealed tube, and reacting at 120 ℃ for 20 hours to obtain the target product (IE) which is yellow solid, wherein the isolated yield is 71 percent, and mp is 164-166 ℃.
Nuclear magnetic data of the product: 1 H NMR(500MHz,CDCl 3 ):δ7.65(d,J＝8.7Hz,4H),7.38-7.35(m,2H),7.24-7.21(m,1H),7.18(s,2H),7.08(d,J＝7.8Hz,2H),6.94(d,J＝8.7Hz,4H),3.85(s,6H),3.64(s,2H)； 13 C{ 1 H}NMR(125MHz,CDCl 3 ):δ193.73,162.04,143.13,140.49,131.37,130.65,129.95,126.31,120.49,116.96,113.61,55.35,22.17。
product high resolution mass spectrometry data: HRMS (ESI) calcd for C 27 H 24 NO 4 [M+H] + :426.1700,found 426.1706.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (4)
1. A synthetic method of 1,4-dihydropyridine derivatives is characterized by comprising the following synthetic steps: firstly, adding an alkaline catalyst, a solvent, an additive and a reducing agent into a reaction bottle to react in the atmosphere of carbon dioxide gas; secondly, adding enamine compounds and acid catalysts into the reaction system of the first step for cyclization reaction to obtain 1,4-dihydropyridine derivatives of the formula (I); the reaction is shown as the formula (II):
in the formula (II), the additive is n-butylamine, the reducing agent is phenylsilane, and the basic catalyst is one or two of 1,5,7-triazabicyclo (4.4.0) dec-5-ene and cesium carbonate; the acid catalyst is selected from one or two of zinc chloride and ferric chloride; the reaction temperature of the first step is 115 ℃, and the reaction temperature of the second step is 120 ℃;
the formula (I) is:
2. the method for synthesizing the 1,4-dihydropyridine derivative according to claim 1, wherein the enamine compound: additive: carbon dioxide: reducing agent: basic catalyst: the molar ratio of the acidic catalyst is 1: (0.5-6): (1-4): (2-10): (0.1-0.5): (0.1-0.5).
3. The method for synthesizing 1,4-dihydropyridine derivatives as claimed in claim 1, wherein the solvent is selected from one or more of acetonitrile, N-dimethylformamide, 1,4-dioxane, 1,2-dichloroethane.
4. The method for synthesizing 1,4-dihydropyridine derivatives as claimed in claim 1, wherein the reaction time of the first step is 6-12h, and the reaction time of the second step is 12-24h.
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