阅读说明：本技术 一种含三氟甲基全碳季碳中心吲哚乙腈化合物及其制备方法和应用 (Trifluoromethyl-containing all-carbon quaternary carbon center indole acetonitrile compound and preparation method and application thereof ) 是由 饶卫东 桑静静 冯丽 商丹丹 胡睿 于 2021-08-31 设计创作，主要内容包括：本发明涉及有机合成技术领域,具体涉及一种含三氟甲基全碳季碳中心吲哚乙腈化合物及其制备方法和应用。所述化合物的制备方法包括,以三氟甲基吲哚醇类化合物和三甲基氰硅烷为原料,在路易斯酸催化剂催化作用下,在溶剂中加热反应得到含三氟甲基全碳季碳中心吲哚乙腈化合物。本发明含三氟甲基全碳季碳中心吲哚乙腈化合物的合成方法以简单易得的三氟甲基吲哚醇类化合物和三甲基氰硅烷为原料、以三(五氟苯基)硼烷为催化剂,无需使用金属催化剂和剧毒的无机氰化物作为氰源,具有反应条件温和,操作简单,并且产率高、反应底物范围较广等优点。(The invention relates to the technical field of organic synthesis, and particularly relates to a trifluoromethyl-containing all-carbon quaternary carbon center indole acetonitrile compound and a preparation method and application thereof. The preparation method of the compound comprises the steps of taking trifluoromethyl indoles alcohol compound and trimethylsilyl cyanide as raw materials, and heating and reacting in a solvent under the catalytic action of a Lewis acid catalyst to obtain the trifluoromethyl all-carbon quaternary carbon center indole acetonitrile compound. The synthetic method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound takes the simple and easily obtained trifluoromethyl indole alcohol compound and the trimethyl cyano silane as raw materials, takes the tris (pentafluorophenyl) borane as a catalyst, does not need to use a metal catalyst and a virulent inorganic cyanide as a cyanogen source, and has the advantages of mild reaction conditions, simple operation, high yield, wide range of reaction substrates and the like.)

1. A trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound is characterized in that the structural formula is shown as the formula (1):

wherein R is¹、R²Are each independently of the other R¹One selected from hydrogen, halogen, C1-C5 linear alkyl, ester group, cyano or methoxy; r²Is selected from one of phenyl, alkyl substituted phenyl, halogen substituted phenyl, trifluoromethyl substituted phenyl, naphthyl, thienyl or C1-C5 straight-chain alkyl.

2. The preparation method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound according to claim 1, which is characterized in that a trifluoromethyl indolealcohol compound and trimethylsilyl cyanide are used as raw materials, and the raw materials are heated and reacted in a solvent under the catalysis of a Lewis acid catalyst to obtain the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound.

3. The preparation method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound as claimed in claim 2, wherein the structural formula of the trifluoromethyl indolealcohol compound is as shown in formula (2);

wherein R is¹、R²Are each independently of the other R¹One selected from hydrogen, halogen, C1-C5 linear alkyl, ester group, cyano or methoxy; r²One selected from phenyl, alkyl substituted phenyl, halogen substituted phenyl, trifluoromethyl substituted phenyl, naphthyl, thienyl or C1-C5 straight-chain alkyl;

the Lewis acid catalyst is tris (pentafluorophenyl) borane.

4. The preparation method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound as claimed in claim 3, wherein the molar ratio of the trifluoromethyl indolol compound to the Lewis acid catalyst is 1: 0.05-1: 0.1.

5. The method for preparing the indole acetonitrile compound containing trifluoromethyl all-carbon quaternary carbon center according to claim 2, wherein the molar ratio of the trifluoromethyl indolol compound to the trimethylsilyl cyanide is 1: 2-3.

6. The method for preparing the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound according to claim 2, wherein the solvent is any one of chlorobenzene, acetonitrile, toluene or dichloroethane; the concentration of the trifluoromethyl indolol compound in the solvent is 0.05-0.5 mol/L.

7. The method for preparing the indole acetonitrile compound containing trifluoromethyl all-carbon quaternary carbon center as claimed in claim 2, wherein the heating reaction temperature is 100 ℃ and the heating reaction time is 8-24 h.

8. The use of the trifluoromethyl containing all-carbon quaternary carbon center indole acetonitrile compound of claim 1 in a medicament for inhibiting sclerotinia rot of colza and botrytis cinerea.

9. Use of the trifluoromethyl all carbon quaternary carbon center containing indole acetonitrile compound of claim 1 in the synthesis of α -trifluoromethyl all carbon quaternary carbon center containing tryptamine derivatives.

Technical Field

The invention relates to the technical field of organic synthesis, and particularly relates to a trifluoromethyl-containing all-carbon quaternary carbon center indole acetonitrile compound and a preparation method and application thereof.

Background

The indole acetonitrile compound is considered as a biological metabolite of tryptophan, is an important indole alkaloid, is widely present in natural products, is a widely applied plant growth regulator, and has various biological activities. For example, the compound A, the compound B (Arvelexin) and the compound C are natural products extracted from the root of the isatis root. The compound A and the compound B (Arvelexin) have better inhibitory action on influenza virus (H3N2) and IC thereof₅₀3.70 and 12.35 mu M respectively. In addition, 4-methoxy indole acetonitrile (compound B, Arvelexin) is also found to have the function of treating colitis. C6-hydroxyglucoside indole acetonitrile (compound C) shows strong inhibition effect on the generation of nitric oxide, and IC thereof₅₀5.87. mu.M, and nitric oxide is a transiently living free radical produced by L-arginine via nitric oxide synthase, which affects every step of inflammation development. The 6-isopentenyl indole acetonitrile (compound D) extracted from parasitic actinomycetes has good inhibitory effect on plant pathogenic bacteria of colletotrichum, phytophthora capsici, watermelon target spot pathogen and radish yellow leaf pathogen. Tenualexin (compound E) extracted from Brassicaceae plant caulis et folium Brassicae Junceae has excellent inhibitory effect on several plant pathogenic bacteria such as cabbage black spot pathogen, caulis et folium Brassicae campestris canker pathogen, Rhizoctonia solani and Sclerotinia sclerotiorum. Furthermore, the indole acetonitrile compounds are also precursors for the synthesis of indole acetic acid, acetamides and other heterocyclic compounds.

Trifluoromethyl (CF)₃) The trifluoromethyl group-containing compound has the characteristics of strong electron withdrawing property, lipophilicity, stable C-F bond and the like, can obviously change the acidity, dipole moment, polarity, lipophilicity, metabolism and chemical stability of the trifluoromethyl group-containing compound, and is widely applied to the fields of medicines, pesticides, materials and the like. In addition, the all-carbon quaternary carbon stereocenter-containing compound has more diverse and rigid structure, so the all-carbon quaternary carbon stereocenter-containing compound is widely existed in drug molecules, natural products and agricultural chemicals, however, the construction of the all-carbon quaternary carbon stereocenter compound is very challenging under the influence of steric hindrance effect. Therefore, the synthesis of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound has important significance.

At present, a plurality of methods for synthesizing indole acetonitrile compounds exist, such as nucleophilic substitution reaction of halogenated compounds and highly toxic inorganic cyanide, but the synthesis of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compounds is not reported in documents at present.

Disclosure of Invention

Based on the content, the invention provides a trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound and a preparation method and application thereof, the all-carbon quaternary carbon stereo center compound is constructed, and the technical blank in the aspect of synthesizing the trifluoromethyl all-carbon quaternary carbon center indole acetonitrile compound is filled.

The technical scheme of the invention is that a trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound has a structural formula shown in a formula (1):

wherein R is¹、R²Are each independently of the other R¹One selected from hydrogen, halogen, C1-C5 linear alkyl, ester group, cyano or methoxy; r²Is selected from one of phenyl, alkyl substituted phenyl, halogen substituted phenyl, trifluoromethyl substituted phenyl, naphthyl, thienyl or C1-C5 straight-chain alkyl.

According to the second technical scheme, the preparation method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound is characterized in that a trifluoromethyl indolealcohol compound and trimethylsilyl cyanide are used as raw materials, and the raw materials are heated and reacted in a solvent under the catalysis of a Lewis acid catalyst to obtain the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound.

Further, the heating reaction process also comprises the following steps: and (3) tracking the reaction by thin-plate chromatography until the reaction is complete, removing the solvent by rotary evaporation after the reaction is finished, and carrying out silica gel column chromatography on the crude product.

Further, the structural formula of the trifluoromethyl indolol compound is shown as a formula (2);

wherein R is¹、R²Are each independently of the other R¹One selected from hydrogen, halogen, C1-C5 linear alkyl, ester group, cyano or methoxy; r²Is selected from one of phenyl, alkyl substituted phenyl, halogen substituted phenyl, trifluoromethyl substituted phenyl, naphthyl, thienyl or C1-C5 straight-chain alkyl.

Further, the lewis acid catalyst is tris (pentafluorophenyl) borane.

Further, the molar ratio of the trifluoromethyl indolol compound to the Lewis acid catalyst is 1: 0.05-1: 0.1.

Further, the molar ratio of the trifluoromethyl indolol compound to the trimethylsilyl cyanide is 1: 2-3.

Further, the solvent is any one of chlorobenzene, acetonitrile, toluene or dichloroethane; the concentration of the trifluoromethyl indolol compound in the solvent is 0.05-0.5 mol/L.

Furthermore, the solvent is chlorobenzene, and the yield is optimal.

Further, the heating reaction temperature is 100-120 ℃, and the heating reaction time is 8-24 h.

According to the third technical scheme, the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound is applied to medicines for inhibiting sclerotinia rot of colza and botrytis cinerea.

The fourth technical scheme of the invention is the application of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound in the synthesis of alpha-trifluoromethyl all-carbon quaternary carbon center-containing tryptamine derivatives.

Compared with the prior art, the invention has the beneficial effects that:

the synthesis method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound takes the simple and easily-obtained trifluoromethyl indole alcohol compound and the trimethylsilyl cyanide as raw materials to complete the reaction under the catalysis of the Lewis acid catalyst, does not need to use a metal catalyst and a virulent inorganic cyanide as a cyanogen source, and has the advantages of mild reaction conditions, simple operation, high yield, wide range of reaction substrates and the like.

Through bacteriostasis experiment tests, the trifluoromethyl-containing all-carbon quaternary carbon center indole acetonitrile compound prepared by the invention has strong inhibition effect on plant pathogenic bacteria, especially sclerotinia sclerotiorum and botrytis cinerea, and can be used for preventing and treating sclerotinia rot of colza and botrytis cinerea.

The prepared trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound is an important organic synthesis intermediate, and can be converted into alpha-trifluoromethyl all-carbon quaternary carbon center-containing tryptamine derivatives through hydrogenation.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise. Wherein:

FIG. 1 is a NMR spectrum of Compound 1a prepared in example 1 of the present invention;

FIG. 2 is a NMR spectrum of Compound 1a prepared in example 1 of the present invention;

FIG. 3 is a NMR fluorine spectrum of Compound 1a prepared in example 1 of the present invention;

FIG. 4 is a single crystal diffractogram of Compound 1a prepared in example 1 of the present invention.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

Example 1:

the reaction equation is as follows:

a10 mL round bottom flask is taken, trifluoromethyl indole alcohol 2a (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) are added, chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol) are sequentially added, the mixture is stirred at 120 ℃ for reaction for 8 hours (thin plate chromatography tracking reaction is carried out until the reaction is complete), after the reaction is finished, the mixture is cooled to room temperature, the reaction mixture is evaporated and concentrated to remove the solvent, and the crude product is separated by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-8/1, V/V) to obtain the target product 1a (89.2mg, white solid, yield 99%).

FIG. 1 is a NMR spectrum of Compound 1a prepared in the example;

FIG. 2 is a NMR carbon spectrum of Compound 1a prepared in the example;

FIG. 3 is a nuclear magnetic resonance fluorine spectrum of Compound 1a prepared in the example;

fig. 4 is a single crystal diffractogram of compound 1a prepared in example.

¹H NMR(600MHz,CDCl₃)δ8.41(s,1H),7.58(d,J＝7.5Hz,2H),7.45–7.38(m,5H),7.22(t,J＝7.6Hz,1H),7.11(d,J＝8.1Hz,1H),7.02(t,J＝7.6Hz,1H)；¹³C NMR(151MHz,CDCl₃)δ136.2,131.6,129.7,128.8,128.5,124.7(q,J＝285.4Hz),124.6,124.1,124.0(q,J＝1.5Hz),123.2,120.8,119.9,116.2,111.5,106.7,52.7(q,J＝30.2Hz)；¹⁹F NMR(565MHz,CDCl₃)δ–69.2；HRMS(ESI)calcd for C₁₇H₁₂F₃N₂[M+H]⁺:301.0947；found:301.0959。

Example 2:

the reaction equation is as follows:

adding trifluoromethyl indolol 2b (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol), stirring at 120 ℃ for reaction for 15 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-8/1, V/V) to obtain the target product 1b (91.9mg, white solid, yield 99%).

¹H NMR(600MHz,CDCl₃)δ8.69(s,1H),7.50(d,J＝7.6Hz,2H),7.47–7.43(m,1H),7.43–7.33(m,3H),7.19(d,J＝8.2Hz,1H),7.12(td,J＝8.0,4.8Hz,1H),6.66(dd,J＝11.0,7.8Hz,1H)；¹³C NMR(101MHz,CDCl₃)δ155.4(d,J＝248.6Hz),138.8(d,J＝10.4Hz),132.5(d,J＝1.2Hz),129.5,128.5,128.3,124.6–123.6(m),123.7(q,J＝286.3Hz),116.5,113.7(d,J＝20.2Hz),107.7(d,J＝3.8Hz),106.4,106.2,105.4(d,J＝3.5Hz),53.1(q,J＝29.8Hz)；¹⁹F NMR(376MHz,CDCl₃)δ-69.0,-115.0；HRMS(ESI)calcd for C₁₇H₁₀F₄N₂Na[M+Na]⁺:341.0672；found:341.0658。

Example 3:

the reaction equation is as follows:

adding trifluoromethyl indolol 2c (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol), stirring at 120 ℃ for reaction for 12 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-8/1, V/V) to obtain the target product 1c (90.7mg, white solid, yield 99%).

¹H NMR(400MHz,CDCl₃)δ8.39(s,1H),7.62(d,J＝7.3Hz,2H),7.49–7.33(m,4H),7.29(d,J＝8.3Hz,1H),7.07(d,J＝8.3Hz,1H),6.95(s,1H),2.32(s,3H)；¹³C NMR(101MHz,CDCl₃)δ134.5,131.6,130.1,129.6,128.8,128.4,124.8,124.7,124.1(q,J＝2.6Hz),123.8(q,J＝286.3Hz),119.1,116.4,111.3,105.6,52.8(q,J＝30.3Hz),21.4；¹⁹F NMR(376MHz,CDCl₃)δ-69.07；HRMS(ESI)calcd for C₁₈H₁₄F₃N₂[M+H]⁺:315.1104；found:315.1092。

Example 4:

the reaction equation is as follows:

adding trifluoromethyl indolol 2d (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol), stirring at 120 ℃ for reaction for 15 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-8/1, V/V) to obtain the target product 1d (109.2mg, white solid, yield 96%).

¹H NMR(600MHz,CDCl₃)δ8.51(s,1H),7.52(d,J＝7.7Hz,2H),7.48–7.34(m,4H),7.31–7.22(m,2H),7.19(s,1H)；¹³C NMR(151MHz,CDCl₃)δ134.9,130.9,129.9,129.0,128.2,126.2,126.1,125.3,123.5(q,J＝285.1Hz),122.0,116.1,114.0,113.2,106.0,52.5(q,J＝30.5Hz)；¹⁹F NMR(565MHz,CDCl₃)δ-69.06；HRMS(ESI)calcd for C₁₇H₁₀BrF₃N₂Na[M+Na]⁺:400.9872；found:400.9874。

Example 5:

the reaction equation is as follows:

adding trifluoromethyl indolol 2e (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol), stirring at 120 ℃ for reaction for 15 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-7/1, V/V) to obtain the target product 1e (90.6mg, white solid, yield 94%).

¹H NMR(600MHz,CDCl₃)δ8.64(s,1H),7.58(d,J＝7.5Hz,2H),7.44–7.37(m,4H),6.94(t,J＝8.0Hz,1H),6.70(d,J＝8.2Hz,1H),6.66(d,J＝7.7Hz,1H),3.96(s,3H)；¹³C NMR(151MHz,CDCl₃)δ146.3,131.8,129.7,128.9,128.6,127.1,126.0,123.7(q,J＝2.1Hz),123.9(q,J＝285.3Hz),121.4,116.4,112.3,107.0,102.9,55.4,52.8(q,J＝30.2Hz)；¹⁹F NMR(565MHz,CDCl₃)δ-69.18；HRMS(ESI)calcd for C₁₈H₁₄F₃N₂O[M+H]⁺:331.1053；found:331.1040。

Example 6:

the reaction equation is as follows:

adding trifluoromethyl indolol 2f (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol) into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol), stirring at 120 ℃ for reaction for 12 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-10/1, V/V) to obtain the target product 1f (90.5mg, white solid, yield 96%).

¹H NMR(600MHz,CDCl₃)δ8.44(s,1H),7.46(d,J＝6.9Hz,2H),7.43–7.37(m,2H),7.25–7.18(m,3H),7.18–7.13(m,1H),7.06–7.01(m,1H),2.37(s,3H)；¹³C NMR(151MHz,CDCl₃)139.8,136.2,129.5,128.6,128.3,124.5,124.0(q,J＝2.2Hz),123.8(q,J＝285.6Hz),123.1,120.6,119.8,116.4,111.6,106.5,52.4(q,J＝31.8Hz),21.0；¹⁹F NMR(565MHz,CDCl₃)δ-69.30；HRMS(ESI)calcd for C₁₈H₁₄F₃N₂[M+H]⁺:315.1104；found:315.1098。

Example 7:

the reaction equation is as follows:

adding 2g (0.3mmol) of trifluoromethyl indolol and 0.03mmol of tris (pentafluorophenyl) borane into a 10mL round-bottom flask, sequentially adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol) under a nitrogen atmosphere, stirring at 120 ℃ for reacting for 24 hours (tracking the reaction by thin plate chromatography till the reaction is complete), cooling to room temperature after the reaction is finished, concentrating the reaction mixture by rotary evaporation to remove the solvent, and separating the crude product by silica gel column chromatography (an eluent is petroleum ether, ethyl acetate is 25/1-8/1, V/V) to obtain 1g (101.9mg, light yellow solid, yield is 97%) of a target product.

¹H NMR(600MHz,CDCl₃)δ8.44(s,1H),8.22(s,1H),7.92–7.87(m,1H),7.87–7.84(m,1H),7.82(d,J＝8.7Hz,1H),7.61–7.53(m,2H),7.51(d,J＝8.5Hz,2H),7.42(d,J＝8.2Hz,1H),7.21(t,J＝7.6Hz,1H),7.13(d,J＝8.2Hz,1H),6.97(t,J＝7.6Hz,1H)；¹³C NMR(151MHz,CDCl₃)δ136.2,133.4,132.7,128.9,128.8,128.6,128.4,127.6,127.4,126.9,124.9,124.6,124.1(q,J＝2.3Hz),123.9(q,J＝285.7Hz),123.2,120.8,119.7,116.3,111.6,106.4,52.9(q,J＝30.2Hz)；¹⁹F NMR(565MHz,CDCl₃)δ-68.80；HRMS(ESI)calcd for C₂₁H₁₃F₃N₂Na[M+Na]⁺:373.0923；found:373.0916。

Example 8:

the reaction equation is as follows:

taking a 10mL round-bottom flask, adding trifluoromethyl indolol for 2h (0.3mmol) and tris (pentafluorophenyl) borane (0.03mmol), adding chlorobenzene (3mL) and trimethylsilyl cyanide (0.9mmol) for times, stirring at 120 ℃ for reaction for 15 hours (thin plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, evaporating and concentrating the reaction mixture to remove the solvent, and separating the crude product by silica gel column chromatography (eluent is petroleum ether: ethyl acetate: 25/1-8/1, V/V) to obtain the target product for 1h (82.9mg, white solid, yield 93%).

Example 9:

in order to verify the practicability of the invention, the invention also carries out gram-scale amplification experiments, when the raw material trifluoromethyl indole alcohol 2a is amplified to 4mmol (1.17 g), the expected product can still be obtained with 90% yield, and the practicability of the invention is fully shown.

The reaction equation is as follows:

adding trifluoromethyl indolol 2a (4mmol) and tris (pentafluorophenyl) borane (0.4mmol) into a 100mL round-bottom flask, sequentially adding chlorobenzene (340mL) and trimethylsilyl cyanide (12mmol) under a nitrogen atmosphere, stirring at 120 ℃ for reaction for 12 hours (thin-plate chromatography tracking reaction till the reaction is complete), cooling to room temperature after the reaction is finished, carrying out rotary evaporation and concentration on a reaction mixture to remove a solvent, and carrying out silica gel column chromatography separation on a crude product (an eluent is petroleum ether: ethyl acetate: 25/1-9/1, V/V) to obtain a target product 1a (1.08g, white solid, yield 90%).

Example 10:

the indole acetonitrile compounds containing the trifluoromethyl all-carbon quaternary carbon center prepared in the embodiments 1-9 are important organic synthesis intermediates, and can be converted into tryptamine derivatives containing alpha-trifluoromethyl all-carbon quaternary carbon center through hydrogenation. For example, 2-trifluoromethyl-2-phenyl-indoleacetonitrile (1a), the reaction equation is as follows:

taking a 10mL round-bottom flask, sequentially adding a trifluoromethyl all-carbon quaternary carbon central indoleacetonitrile compound 1a (0.3mmol), cobalt dichloride (0.6mmol) and di-tert-butyl dicarbonate (1.2mmol), then adding methanol (3mL), adding sodium borohydride in batches within ten minutes of ice bath, reacting at room temperature for 15 hours (thin plate chromatography tracking reaction till the reaction is complete) after the reaction is finished, rotationally concentrating to remove the solvent after the reaction is finished, and performing gradient elution by using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 20: 1-6: 1 as an eluent to obtain the alpha-trifluoromethyl all-carbon quaternary carbon central chromoamine derivative 3(64.3mg, white solid, yield 53%).

¹H NMR(600MHz,CDCl₃)δ8.61(s,1H),7.43(s,1H),7.39(t,J＝8.7Hz,3H),7.34–7.28(m,3H),7.14(t,J＝7.6Hz,1H),6.87(t,J＝7.5Hz,1H),6.71(d,J＝8.1Hz,1H),4.47(d,J＝8.6Hz,2H),4.20(d,J＝8.8Hz,1H),1.35(d,J＝26.2Hz,9H)；¹³C NMR(151MHz,CDCl₃)δ155.5,136.4,129.0,128.3,128.0,125.5,125.4(q,J＝276.2Hz),124.7,122.2,121.2,119.7,111.4,79.6,54.1(q,J＝24.5Hz),44.4,28.2；¹⁹F NMR(565MHz,CDCl₃)δ-68.36(d,J＝9.3Hz),-68.73；HRMS(ESI)calcd for C₂₂H₂₄F₃N₂O₂[M+H]⁺:405.1784；found:405.1777。

Example 11:

on the basis of example 1, the reaction conditions were optimized, and the optimization results are shown in table 1.

TABLE 1

Therefore, the synthesis method of the trifluoromethyl all-carbon quaternary carbon center-containing indole acetonitrile compound provided by the invention can realize that the trifluoromethyl and the cyano are simultaneously introduced into an indole skeleton, and the method adopts a nonmetal catalyst, so that the method has the advantages of simple operation, wide substrate range, high yield and the like.

Example 12:

sclerotinia sclerotiorum is a worldwide important plant pathogen that harms crops and vegetables, and can widely infect many monocotyledonous and dicotyledonous plants. Botrytis cinerea, also called Botrytis cinerea, is a broad-host strain capable of causing damping-off, leaf drop, flower rot, rotten fruit and rotten cellar of various plant seedlings, fruits and storage organs. When wet, the surface layer of the diseased part produces a large number of gray mold layers (conidiophores and conidia), called gray mold. It is widely distributed in the air, not only can infect field crops, but also can cause huge loss to the postharvest stage of plants.

The compound 1a prepared in example 1 was subjected to a sclerotinia sclerotiorum and botrytis cinerea inhibition test, which was as follows:

the plant fungi used in the experiment are sclerotinia sclerotiorum and botrytis cinerea which are preserved at 4 ℃ in a laboratory. The adopted culture medium is a potato agar glucose culture medium (PDA for short). The PDA culture medium formula comprises 200g of potato (peeled), 20g of glucose, 15g of agar and 1000mL of distilled water, and the preparation method comprises the following steps: cleaning and peeling potatoes, weighing 200g of potatoes, cutting the potatoes into small pieces, adding water, boiling the potatoes thoroughly (boiling for 20-30 minutes and being capable of being punctured by a glass rod), filtering the potatoes in a beaker by eight layers of gauze, adding 15-20g of agar according to experimental requirements, adding 20g of glucose, stirring the mixture evenly, slightly cooling the mixture after the mixture is fully dissolved, supplementing water to 1000mL, sterilizing the mixture for 30 minutes at 121 ℃ after split charging, and cooling the mixture for later use.

The experimental method comprises the following steps: a growth rate method is used.

(1) Firstly, 2 plant fungi are cultured on a PDA flat plate at 25 ℃ for about 3-6 days for later use;

(2) heating and melting PDA culture medium, cooling to 45-50 deg.C, adding 50mg/L of the compound (1a) to be tested to obtain culture medium containing 50mg/L medicinal liquid, and respectively pouring into culture dishes for cooling, and using boscalid (boscalid) as positive control;

(3) taking a circular fungus cake (diameter is 0.50cm) from the edge of each strain hypha cultured for 6d (growth conditions are consistent as much as possible) by using a puncher in an aseptic operation procedure, picking the circular fungus cake to the center of a drug-containing flat plate by using an inoculating needle, and then placing the culture dish in an incubator (28 ℃) for culture;

(4) observing and measuring the growth condition of hyphae at different time after treatment, measuring the diameter by adopting a cross method, processing data and calculating the inhibition rate;

(5) inhibition (%) × (control hypha diameter-treated hypha diameter)/(control hypha diameter-0.5) × 100;

(6) each treatment was repeated 3 times.

The test results are shown in Table 2.

TABLE 2

NO.50mg/L	Sclerotinia sclerotiorum	Botrytis cinerea
			1a	93.5±0.7	90.7±1.9
Boscalid	100.0±0.0	75.3±2.0

As can be seen from the data in table 2, the compound 1a has the activity of inhibiting the plant pathogenic fungi sclerotinia sclerotiorum and botrytis cinerea (also called botrytis cinerea), the inhibition effect of the compound 1a on botrytis cinerea is obviously stronger than that of the positive control boscalid, and the inhibition effect on sclerotinia sclerotiorum is slightly weaker than that of the positive control boscalid, but the inhibition effect is still excellent.

The performance of the other compounds in the examples of the present invention was verified by the method of example 12, and the results showed that each compound also had an excellent plant pathogenic fungus inhibitory effect.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included therein.