A 1,5-disubstituted-4-bromopyrazole compound, a preparation method and application thereof

Abstract

The application belongs to the technical field of organic synthesis, and particularly relates to a 1,5-disubstituted-4-bromopyrazole compound, a preparation method and application thereof. The preparation method of the 1,5-disubstituted-4-bromopyrazole compound comprises the following steps: mixing an enaminone compound, a hydrazine compound, a bromination reagent, a photocatalyst, an additive and a polar organic solvent to perform a ring-forming and regioselective bromination reaction, and obtaining the 1,5-disubstituted-4-bromopyrazole compound. The preparation method has the advantages of wide substrate range, good functional group tolerance, high regioselectivity, simple operation, mild conditions and the like, and the prepared 1,5-disubstituted-4-bromopyrazole compound has high purity, and the purity is 98.5-99.9%.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic synthesis, and particularly relates to a 1,5-disubstituted-4-bromopyrazole compound, a preparation method and application thereof. BACKGROUND

[0002] Pyrazole, as a five-membered heterocyclic skeleton containing double nitrogen, has good biological activity and is regarded as an advantageous skeleton for the research and development of medicines and pesticides. For example, velsaroxine has analgesic and central nervous system inhibitor properties, tepoxalin, deracoxib and celecoxib have analgesic and antipyretic activities, and pyraclostrobin has potential antifungal activity for preventing and treating plant diseases. In addition, pyrazole is also used as a reaction building block, a chiral auxiliary agent and an important directing group. In view of the multiple functions of pyrazole derivatives, it is of great significance to explore a simple and practical method for constructing pyrazole derivatives with various substituents.

[0003] At present, the methods for synthesizing bromopyrazole derivatives mainly include:

[0004] (a) G.G. Levkovskaya et al. (Levkovskaya, G G, Bozhenkov, G V, Larina, L I, Mirskova, A N. New Synthesis and Properties of 3-Alkyl-, 3-Chloroalkyl-, 3-Perfluoroalkyl-, and 3-Aryl-1-methyl-(5-halo)pyrazoles from Chloro(bromo)vinyl Ketones and N,N-Dimethylhydrazine [J]. Russian Journal of Organic Chemistry, 2002, 38: 1501-1506. DOI: 10.1023 / a:1022564707537) reported that 2,2-dibromo(chloro)vinyl ketone and N,N-dimethylhydrazine were used as substrates, and 3-substituted 1-methyl(5-halogen)pyrazole compounds were generated by demethylation, and the reaction formula is as follows:

[0005]

[0006] (b) Yang Yiwen et al. (Yang Y, Kuang C, Jin H, Yang Q, Zhang Z. Efficient synthesis of 1,3-diaryl-4-halo-1H-pyrazoles from 3-arylsydnones and 2-aryl-1,1-dihalo-1-alkenes[J]. Beilstein Journal of Organic Chemistry, 2011, 7(1): 1656-1662. DOI: 10.3762 / bjoc.7.195.) reported that 1,1-dihalo-2-arylethylene and 3-arylydnones can be conveniently and efficiently synthesized into 1,3-diaryl-4-halopyrazole compounds after alkaline reaction. However, the narrow functional group compatibility of dihaloalkenes limits the expansion of the substrate range. The reaction formula is as follows:

[0007]

[0008] (c) Ramesh C. Samanta et al. (Samanta RC, Yamamoto H. Selective halogenation using an aniline catalyst[J]. Chemistry-A European Journal, 2015, 21(34):11976-11979. DOI:10.1002 / chem.201502234.) reported the use of aniline as a catalyst for selective halogenation reactions, with N-bromosuccinimide as a bromine source for the selective halogenation of aromatic and heteroaromatic compounds as well as unactivated double bonds, to obtain 4-bromo-1-phenyl-1H-pyrazoles, for example:

[0009]

[0010] (d) Targos K et al. (Targos K, Williams OP, Wickens Z K. Unveiling potent photooxidation behavior of catalytic photoreductants[J]. Journal of the American Chemical Society, 2021, 143(11):4125-4132. DOI:10.1021 / jacs.1c00399.) reported the release of potent photooxidants from the most reducing conventional photoredox catalyst PTH (N-phenylphenthiazide). This method enables the oxidation of C(SP) via the photooxidation of aromatic substrates.2 )-N coupling yields 4-bromo-1-phenyl-1H-pyrazole, for example:

[0011]

[0012] However, the above four methods either use halogenated olefins, or pyrazoles and bromopyrazoles as raw materials, which limits the types of raw materials that can be selected and restricts the substrate range. Summary of the Invention

[0013] In view of this, the object of the present invention is to provide a 1,5-disubstituted-4-bromopyrazole compound, its preparation method, and its application. The preparation method of the present invention has the advantages of a broad substrate range and good functional group tolerance, and is also simple and under mild conditions.

[0014] This invention provides a method for preparing 1,5-disubstituted-4-bromopyrazole compounds, comprising the following steps:

[0015] Enaminoketone compounds, hydrazine compounds, brominating reagents, photocatalysts, additives, and polar organic solvents were mixed and subjected to cyclization and regioselective bromination reactions to obtain 1,5-disubstituted-4-bromopyrazole compounds.

[0016] The enaminoketone compounds have the structure shown in Formula I, the hydrazine compounds have the structure shown in Formula II, and the 1,5-disubstituted-4-bromopyrazole compounds have the structure shown in Formula III.

[0017]

[0018] R1 is aryl, substituted aryl, or alkyl; R2 is aryl, substituted aryl, hydrogen, or acyl.

[0019] Preferably, R1 includes phenyl, halophenyl, trifluoromethylphenyl, alkylphenyl, alkoxyphenyl, nitrophenyl, cyanophenyl, naphthyl, biphenyl, methylenedioxyphenyl, furanyl, pyridyl, isopropyl, propyl, tridecyl, cyclopropyl, cyclobutyl, cyclohexyl, or adamantyl.

[0020] Preferably, the enaminoketone compounds include (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-fluorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-chlorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-bromophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-iodophenyl)-2-propen-1-one, (E)-3-( (E)-3-(dimethylamino)-1-(4-nitrophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-methoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-ethoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-methoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-methylphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-cyanophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(2-bromophenyl) (E)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3,4-chlorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-naphthyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(6-methoxynaphthyl-2-yl)-2-propen-1-one, 3-(dimethylamino)-1-biphenyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(benzo[d][1,3]dioxacyclopenten-5-yl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(furan-2-yl)-2-propen-1-one 3-(dimethylamino)-1-(2-pyridine)-2-propen-1-one, 3-(dimethylamino)-1-isopropyl-2-propen-1-one, 3-(dimethylamino)-1-propyl-2-propen-1-one, 3-(dimethylamino)-1-tetrazyl-2-propen-1-one, 3-(dimethylamino)-1-cyclopropyl-2-propen-1-one, 3-(dimethylamino)-1-cyclobutyl-2-propen-1-one, 3-(dimethylamino)-1-cyclohexyl-2-propen-1-one or 3-(dimethylamino)-1-((3r,5r,7r)-adamantane-1-yl)-2-propen-1-one.

[0021] Preferably, R2 includes phenyl, halophenyl, cyanophenyl, alkylphenyl, alkoxyphenyl, nitrophenyl, naphthalyl, pyridyl, pyrazinyl, benzyl, hydrogen, benzenesulfonyl or isobutyricyl.

[0022] Preferably, the hydrazine compounds include phenylhydrazine, 4-fluorophenylhydrazine, 4-chlorophenylhydrazine, 4-bromophenylhydrazine, 4-cyanophenylhydrazine, 4-trifluoromethylphenylhydrazine, 4-methoxyphenylhydrazine, 3-fluorophenylhydrazine, 3-chlorophenylhydrazine, 3-bromophenylhydrazine, 3-nitrophenylhydrazine, 4-nitrophenylhydrazine, 3-methoxyphenylhydrazine, 2-methylphenylhydrazine, 2-fluorophenylhydrazine, 3,5-dimethylphenylhydrazine, 3,4-dichlorophenylhydrazine, 1-benzylhydrazine, 1-naphthylhydrazine, 2-hydrazylpyridine, 2-hydrazylpyrazine, hydrazine hydrate, benzylsulfonylhydrazine, or isobutyric acid hydrazine.

[0023] Preferably, the brominating agent includes carbon tetrabromide or N-bromosuccinimide, and the molar ratio of the enamine ketone compound, hydrazine compound and carbon tetrabromide is 1:(1-3):(1-3).

[0024] Preferably, the photocatalyst is tris(2-phenylpyridine)iridium, tris(2,2'-bipyridyl)ruthenium(II) chloride hexahydrate, di[2-(2,4-difluorophenyl)-5-trifluoromethylpyridine][2-2'-bi(4-tert-butylpyridine)]iridium di(hexafluorophosphate), Eosin Y, or Bengal rose red; the additive is tetrabutylammonium bromide, pyridine, tetrabutylammonium hydrogen phosphate, triethylamine, lithium bromide, potassium bromide, or polyethylene glycol.

[0025] Preferably, the cyclization and regioselective bromination reaction is carried out at room temperature for 3–24 hours.

[0026] The present invention also provides 1,5-disubstituted-4-bromopyrazole compounds, including any of the following structural formulas:

[0027]

[0028]

[0029] The present invention also provides the application of the 1,5-disubstituted-4-bromopyrazole compounds described in the above technical solution in the preparation of pharmaceutical or pesticide intermediates, or as raw materials for the preparation of pharmaceuticals or pesticides.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This invention provides a method for preparing 1,5-disubstituted-4-bromopyrazole compounds. The method uses enaminoketone compounds, hydrazine compounds, and brominating reagents (carbon tetrabromide or NBS) as raw materials. The enaminoketone compounds and hydrazine compounds, even with different substituents, remain well-suited to the reaction, resulting in a one-pot synthesis of bromopyrazole compounds. This method offers advantages such as mild conditions, simple operation, economical steps, readily available and inexpensive raw materials, a broad substrate range, and good functional group tolerance. Furthermore, the prepared 1,5-disubstituted-4-bromopyrazole compounds exhibit high purity, ranging from 98.5% to 99.9%. Compared to multi-step synthetic reactions, this invention achieves the target product in a one-pot process with a yield of up to 91%, demonstrating high reaction efficiency and economical steps. Detailed Implementation

[0032] This invention provides a method for preparing 1,5-disubstituted-4-bromopyrazole compounds, comprising the following steps:

[0033] Enaminoketone compounds, hydrazine compounds, brominating reagents, photocatalysts, additives, and organic solvents were mixed and subjected to cyclization and regioselective bromination reactions to obtain 1,5-disubstituted-4-bromopyrazole compounds.

[0034] The enaminoketone compounds have the structure shown in Formula I, the hydrazine compounds have the structure shown in Formula II, and the 1,5-disubstituted-4-bromopyrazole compounds have the structure shown in Formula III.

[0035]

[0036] R1 is aryl, substituted aryl, or alkyl; R2 is aryl, substituted aryl, hydrogen, or acyl.

[0037] Unless otherwise specified, all materials and equipment used in this invention are commercially available products in the field.

[0038] In this invention, R1 preferably includes phenyl, halophenyl, trifluoromethylphenyl, alkylphenyl, alkoxyphenyl, nitrophenyl, cyanophenyl, naphthyl, biphenyl, heterocyclic, cycloalkyl, or chain alkyl; the halophenyl preferably includes fluorophenyl, chlorophenyl, bromophenyl, or iodophenyl; the alkylphenyl preferably includes tolyl; the alkoxyphenyl preferably includes methoxyphenyl; the heterocyclic preferably includes furanyl, methylenedioxyphenyl, or pyridyl; the cycloalkyl preferably includes cyclopropyl, cyclobutyl, cyclohexyl, or adamantyl; and the chain alkyl preferably includes isopropyl, propyl, or tridecyl.In this invention, the enaminoketone compounds preferably include (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-fluorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-chlorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-bromophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-iodophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-trifluoromethylphenyl)-2-propen-1-one, (E)- 3-(dimethylamino)-1-(4-nitrophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-methoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(4-ethoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-methoxyphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-methylphenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(3-cyanophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(2 (E)-3-(dimethylamino)-1-(3,4-chlorophenyl)-2-propen-1-one, (E)-3-(dimethylamino)-1-naphthyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(6-methoxynaphthyl-2-yl)-2-propen-1-one, 3-(dimethylamino)-1-biphenyl-2-propen-1-one, (E)-3-(dimethylamino)-1-(benzo[d][1,3]dioxacyclopenten-5-yl)-2-propen-1-one, (E)-3-(dimethylamino)-1-(furan-2-yl)-2-propen-1-one Ketones, 3-(dimethylamino)-1-(2-pyridine)-2-propen-1-one, 3-(dimethylamino)-1-isopropyl-2-propen-1-one, 3-(dimethylamino)-1-propyl-2-propen-1-one, 3-(dimethylamino)-1-tetrazyl-2-propen-1-one, 3-(dimethylamino)-1-cyclopropyl-2-propen-1-one, 3-(dimethylamino)-1-cyclobutyl-2-propen-1-one, 3-(dimethylamino)-1-cyclohexyl-2-propen-1-one or 3-(dimethylamino)-1-((3r,5r,7r)-adamantane-1-yl)-2-propen-1-one.

[0039] Introducing the thermoelectric properties of chemicals in the field of photoinduced “(1)Huo,J.andGeng,X.andLi,W.andZhang,P.andWang,L.Photoinduced Three-Component Cyclization of Arylamines,Enaminones and Difluorobromoacetates to2,3-Difunctionalized Quinolines.Adv.Synth.Catal.2022,364,3539-3543.DOI:10.1002 / adsc.202200615(2)Liang X,Guo P,Yang W,Li M,Jiang C,Sun W,Loh TP,Jiang W.Stereoselectivesynthesis of trifluoromethyl-substituted2H-furan-amines from enaminones[J].Chemical Communications,2020,56(13):2043-2046.DOI:10.1039 / C9CC08582C6(3)Qian,Y.Schürmann,M.Janning,P.Hedberg,C.Waldmann,H.Activity-Based ProteomeProfiling Probes Based on Woodward's Reagent K with Distinct TargetSelectivity.Angew.Chem.Int.Ed.,2016,55,7766-7771.DOI:10.1002 / anie.201602666(4)Stanek ,J.Caravatti,G.Capraro,H.-G.Furet,P.Mett,H.Schneider,P.Regenass,US-Adenosylmethionine Decarboxylase Inhibitors:New Aryl andHeteroaryl Analogs ofMethylglyoxal Bis(guanylhydrazone).J.Med.Chem.1993,36,46-54.DOI:10.1021 / jm00053a007;(5)Wu,W.,Wu,X.,Fan,S.Zhu,J.The preparation was carried out according to the content in "Rh(III)-CatalyzedEnaminone-Directed CH Coupling with Diazodicarbonyls for Skeleton-Divergent Synthesis of Isocoumarins and Naphthalenes. Org. Lett. 2022, 24, 7850-7855. DOI:10.1021 / acs.orglett.2c03288.".

[0040] In this invention, R2 preferably includes phenyl, halophenyl, cyanophenyl, alkylphenyl, alkoxyphenyl, nitrophenyl, naphthalyl, pyridyl, pyrazinyl, benzyl, hydrogen, benzenesulfonyl or isobutyricyl; halophenyl preferably includes fluorophenyl, chlorophenyl or bromophenyl; alkylphenyl preferably includes tolyl; alkoxyphenyl preferably includes methoxyphenyl.

[0041] In this invention, the hydrazine compounds preferably include phenylhydrazine, 4-fluorophenylhydrazine, 4-chlorophenylhydrazine, 4-bromophenylhydrazine, 4-cyanophenylhydrazine, 4-trifluoromethylphenylhydrazine, 4-methoxyphenylhydrazine, 3-fluorophenylhydrazine, 3-chlorophenylhydrazine, 3-bromophenylhydrazine, 3-nitrophenylhydrazine, 4-nitrophenylhydrazine, 3-methoxyphenylhydrazine, 2-methylphenylhydrazine, 2-fluorophenylhydrazine, 3,5-dimethylphenylhydrazine, 3,4-dichlorophenylhydrazine, 1-benzylhydrazine, 1-naphthylhydrazine, 2-hydrazylpyridine, 2-hydrazylpyrazine, hydrazine hydrate, benzylsulfonylhydrazine, or isobutyric acid hydrazine.

[0042] In this invention, the brominating agent preferably includes carbon tetrabromide or N-bromosuccinimide, and the molar ratio of the enamine ketone compound, hydrazine compound and carbon tetrabromide is preferably 1:(1-3):(1-3), more preferably 1:2:2.

[0043] In this invention, the polar organic solvent preferably includes one or more of acetonitrile, ethanol, water, dimethyl sulfoxide, N,N-dimethylformamide, and ethyl acetate. The preferred molar ratio of the polar organic solvent to the enamine ketone compound is 1 L:(0.1-1) mol, more preferably 1 L:0.1 mol.

[0044] In this invention, the photocatalyst is preferably tris(2-phenylpyridine)iridium(Ir(ppy)3), tris(2,2'-bipyridyl)ruthenium(II) chloride hexahydrate, di[2-(2,4-difluorophenyl)-5-trifluoromethylpyridine][2,2'-bi(4-tert-butylpyridine)]iridium di(hexafluorophosphate), Eosin Y, or Bengal rose red. The amount of the photocatalyst added is preferably 0.5-10 mol% of an enamine ketone compound, more preferably 1-3 mol%, and even more preferably 2 mol%. Under photocatalysis, the brominating reagent generates bromine radicals, which attack the 4-position of the pyridine ring to obtain 4-bromo-1,5-disubstituted pyrazole. The wavelength range of the light used for the photocatalyst is preferably 360-1000 nm.

[0045] In this invention, the additive is preferably tetrabutylammonium bromide (TBAB), pyridine, tetrabutylammonium hydrogen phosphate, triethylamine, lithium bromide, potassium bromide, or polyethylene glycol, and the amount of TBAB added is preferably 10-100 mol% of an enamine ketone compound, more preferably 50 mol%.

[0046] In this invention, the cyclization and regioselective bromination reactions are preferably carried out at room temperature, under light and stirring conditions, for a time preferably 3–24 h, more preferably 12 h. The light source is preferably blue LEDs (465 nm), and the light intensity is preferably 5–30 W, more preferably 10 W. This invention does not have special requirements for the stirring speed; a commonly used stirring speed in the art is sufficient to ensure the smooth progress of the reaction. This invention mixes enamine ketone compounds, hydrazine compounds, carbon tetrabromide (CBr4), a photocatalyst (Ir(ppy)3), a phase transfer catalyst (TBAB), and a polar organic solvent (MeCN) in a one-pot process. First, a disubstituted pyrazole (1,5-disubstituted-1H-pyrazole) is formed, followed by the regioselective bromination of the pyrazole. The 4-position of the pyrazole ring has the highest electron density, which is favorable for the attack of bromine radicals, yielding 1,5-disubstituted-4-bromopyrazole compounds. The reaction formula is as follows (1 mL of solvent is relative to 0.1 mmol of enamine ketone compound):

[0047]

[0048] In this invention, the cyclization and regioselective bromination reaction preferably further includes purifying the resulting product system. The purification method is preferably column chromatography, and the eluent used in the column chromatography is preferably a mixed solvent of petroleum ether and ethyl acetate; the volume ratio of petroleum ether to ethyl acetate in the mixed solvent is preferably 1–20:1, more preferably 10–20:1. This invention does not have special requirements for the specific process of the column chromatography; methods well known to those skilled in the art can be used. This invention utilizes petroleum ether and ethyl acetate as eluents for purification, resulting in a high purity of the target compound, reaching up to 99.9%.

[0049] The purity of the 1,5-disubstituted-4-bromopyrazole compounds prepared by this invention is preferably 98.5-99.9%; the yield is preferably 15-91%, more preferably 70-91%.

[0050] The present invention also provides 1,5-disubstituted-4-bromopyrazole compounds, including any of the following structural formulas:

[0051]

[0052]

[0053] This invention provides a method for preparing 1,5-disubstituted-4-bromopyrazole compounds with higher yields compared to the preparation of chlorinated compounds.

[0054] The present invention also provides the application of the 1,5-disubstituted-4-bromopyrazole compounds described in the above technical solution in the preparation of pharmaceutical or pesticide intermediates, or as raw materials for the preparation of pharmaceuticals or pesticides.

[0055] In this invention, the 1,5-disubstituted-4-bromopyrazole compounds can undergo suzuli coupling reaction, Sonogashira coupling reaction, nitro reduction reaction or N-alkylation reaction to be converted into pharmaceutical or pesticide products.

[0056] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of the 1,5-disubstituted-4-bromopyrazole compounds, their preparation methods, and applications provided by the present invention, should not be construed as limiting the scope of protection of the present invention.

[0057] In the embodiments of the present invention, mol% are all calculated as enamine ketone compounds.

[0058] Example 1

[0059] The 4-bromo-1,5-diphenyl-1H-pyrazole compound obtained in this example has the following structure:

[0060]

[0061] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1,5-diphenyl-1H-pyrazole compound was obtained with a yield of 81% and a purity of 99.9%.

[0062] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0063] 1 H NMR (400MHz, CDCl3, ppm) δ7.77 (s, 1H), 7.38-7.34 (m, 3H), 7.29 (dd, J = 5.0, 2.8Hz, 5H), 7.23 (dd, J = 7.9, 1.9Hz, 2H).

[0064] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.0,140.4,139.8,130.0,128.9,128.8,128.5,128.4,127.6,124.7,95.8.

[0065] MS(EI,70eV)m / z 298,218,190,180,165.

[0066] Example 2

[0067] The 4-bromo-5-(4-fluorophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0068]

[0069] 0.1 mmol (E)-3-(dimethylamino)-1-(4-fluorophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-5-(4-fluorophenyl)-1-phenyl-1H-pyrazole compound, was obtained with a yield of 74% and a purity of 99.9%.

[0070] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0071] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.35-7.19 (m, 7H), 7.05 (t, J = 8.6Hz, 2H).

[0072] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ 164.0, 161.5, 141.0, 139.6, 139.4, 131.9 (d, J = 8.4Hz), 128.9, 127.7, 124.7, 115.8, 115.6, 95.8.

[0073] MS(EI,70eV)m / z 316,236,216,208,198.

[0074] Example 3

[0075] The 4-bromo-5-(4-chlorophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0076]

[0077] 0.1 mmol (E)-3-(dimethylamino)-1-(4-chlorophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-5-(4-chlorophenyl)-1-phenyl-1H-pyrazole compound, was obtained with a yield of 77% and a purity of 99.9%.

[0078] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0079] 1 H NMR (400MHz, CDCl3, ppm) δ7.76 (s, 1H), 7.35-7.28 (m, 5H), 7.21 (d, J = 8.3Hz, 4H).

[0080] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.0,139.5,139.1,135.0,131.2,128.9,128.8,127.8,126.8,124.7,95.9.

[0081] MS(EI,70eV)m / z 332,298,270,252,225.

[0082] Example 4

[0083] The 4-bromo-5-(4-bromophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0084]

[0085] 0.1 mmol (E)-3-(dimethylamino)-1-(4-bromophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-5-(4-bromophenyl)-1-phenyl-1H-pyrazole compound, was obtained with a yield of 79% and a purity of 99.9%.

[0086] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0087] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.49 (d, J = 8.5Hz, 2H), 7.34-7.28 (m, 3H), 7.21 (dd, J = 8.0, 1.8Hz, 2H), 7.15 (d, J = 8.5Hz, 2H).

[0088] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.1,139.5,139.1,131.7,131.4,129.0,127.8,127.3,124.7,123.3,95.9.

[0089] MS(EI,70eV)m / z 378,298,271,258,218

[0090] Example 5

[0091] The 4-bromo-5-(4-iodophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0092]

[0093] 0.1 mmol (E)-3-(dimethylamino)-1-(4-iodophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-5-(4-iodophenyl)-1-phenyl-1H-pyrazole compound, was obtained with a yield of 79% and a purity of 99.9%.

[0094] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0095] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.69 (d, J = 8.5Hz, 2H), 7.35-7.28 (m, 3H), 7.21 (dd, J = 8.0, 1.8Hz, 2H), 7.01 (d, J = 8.5Hz, 2H).

[0096] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.1,139.5,139.2,137.6,131.5,129.0,127.8,124.7,95.9,95.3.

[0097] MS(EI,70eV)m / z 424,344,318,306,298.

[0098] Example 6

[0099] The 4-bromo-5-(4-trifluoromethylphenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0100]

[0101] 0.1 mmol (E)-3-(dimethylamino)-1-(4-trifluoromethylphenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-5-(4-trifluoromethylphenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 77% and a purity of 99.9%.

[0102] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0103] 1 H NMR (400MHz, CDCl3, ppm) δ7.78 (s, 1H), 7.62 (d, J = 8.2Hz, 2H), 7.41 (d, J = 8.1Hz, 2H), 7.33 (d, J = 7.5Hz, 3H), 7.20 (dd, J = 7.6, 2.1Hz, 2H).

[0104] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.3,139.4,138.8,130.3,129.1,128.1,125.49,125.45,125.41,125.38,124.8,96.3.

[0105] MS(EI,70eV)m / z 366,347,297,286,267.

[0106] Example 7

[0107] The 4-bromo-5-(4-nitrophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0108]

[0109] 0.1 mmol (E)-3-(dimethylamino)-1-(4-nitrophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(4-nitrophenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 76% and a purity of 99.9%.

[0110] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0111] 1 H NMR (400MHz, CDCl3, ppm) δ8.20(d,J=8.8Hz,2H),7.79(s,1H),7.46(d,J=8.8Hz,2H),7.34(dd,J=5.1,1.6Hz,3H),7.19(dd,J=6.8,2.9Hz,2H).

[0112] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ147.6,141.4,139.2,138.0,134.8,130.8,129.2,128.3,124.8,123.6,96.7.

[0113] MS(EI,70eV)m / z 343,313,298,285,263.

[0114] Example 8

[0115] The 4-bromo-5-(4-methoxyphenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0116]

[0117] 0.1 mmol (E)-3-(dimethylamino)-1-(4-methoxyphenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(4-methoxyphenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 74% and a purity of 99.9%.

[0118] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0119] 1 H NMR (400MHz, CDCl3, ppm) δ7.74 (s, 1H), 7.34-7.16 (m, 7H), 6.88 (d, J = 8.8Hz, 2H), 3.81 (s, 3H).

[0120] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ159.8,140.8,140.2,139.9,131.2,128.8,127.5,124.7,120.6,113.9,95.5,55.1.

[0121] MS(EI,70eV)m / z 328,313,285,248,234.

[0122] Example 9

[0123] The 4-bromo-5-(4-ethoxyphenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0124]

[0125] 0.1 mmol (E)-3-(dimethylamino)-1-(4-ethoxyphenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(4-ethoxyphenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 70% and a purity of 99.9%.

[0126] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0127] 1 H NMR (400MHz, CDCl3, ppm) δ7.74 (s, 1H), 7.32-7.22 (m, 5H), 7.18 (d, J = 8.8Hz, 2H), 6.87 (d, J = 8.8Hz, 2H), 4.03 (q, J = 7.0Hz, 2H), 1.41 (s, 3H).

[0128] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ159.2,140.8,140.3,139.9,131.2,128.8,127.4,124.6,120.4,114.3,95.5,63.4,14.7.

[0129] MS(EI,70eV)m / z 342,314,299,285,262.

[0130] Example 10

[0131] The 4-bromo-5-(3-methoxyphenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0132]

[0133] 0.1 mmol (E)-3-(dimethylamino)-1-(3-methoxyphenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(3-methoxyphenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 73% and a purity of 99.9%.

[0134] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0135] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.31 (d, J = 7.6Hz, 3H), 7.24 (dd, J = 7.6, 5.6Hz, 3H), 6.91 (d, J = 10.7Hz, 1H), 6.83 (d, J = 8.1Hz, 2H), 3.71 (s, 3H).

[0136] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ159.3,141.0,140.2,139.8,129.6,129.5,128.9,127.6,124.7,122.3,115.2,114.8,95.8,55.2.

[0137] MS(EI,70eV)m / z 328,313,298,285,248.

[0138] Example 11

[0139] The 4-bromo-5-(3-cyanophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0140]

[0141] 0.1 mmol (E)-3-(dimethylamino)-1-(3-cyanophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(3-cyanophenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 31% and a purity of 99.9%.

[0142] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0143] 1 H NMR (400MHz, CDCl3, ppm) δ7.78 (s, 1H), 7.65 (ddd, J=5.1, 3.6, 1.6Hz, 1H), 7.60 (d, J=1 .2Hz,1H),7.49-7.46(m,2H),7.34(dd,J=5.1,1.9Hz,3H),7.18(dd,J=5.0,1.7Hz,2H).

[0144] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.3,139.1,137.9,134.2,133.2,132.3,129.9,129.4,129.2,128.3,124.8,118.0,112.9,96.4.

[0145] MS(EI,70eV)m / z 323,308,298,243,216.

[0146] Example 12

[0147] The 4-bromo-5-(2-bromophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0148]

[0149] 0.1 mmol (E)-3-(dimethylamino)-1-(2-bromophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-5-(2-bromophenyl)-1-phenyl-1H-pyrazole compound, was obtained with a yield of 16% and a purity of 99.9%.

[0150] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0151] 1 H NMR (400MHz, CDCl3, ppm) δ7.78 (s, 1H), 7.63 (dd, J=7.9, 1.0Hz, 1H), 7.35 (td, J=7.5, 1.3Hz, 1H), 7.31-7.21 (m, 7H).

[0152] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ140.5,140.0,139.7,133.1,132.5,131.1,130.4,128.8,127.6,127.5,124.7,123.7,97.3.

[0153] MS(EI,70eV)m / z 378,297,260,231,218.

[0154] Example 13

[0155] The 4-bromo-5-(3,4-dichlorophenyl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0156]

[0157] 0.1 mmol (E)-3-(dimethylamino)-1-(3,4-dichlorophenyl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(3,4-dichlorophenyl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 80% and a purity of 99.9%.

[0158] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0159] 1 H NMR (400MHz, CDCl3, ppm) δ7.76 (s, 1H), 7.43 (d, J = 2.0Hz, 1H), 7.41 (d, J = 8.3Hz, 1H ),7.35(d,J=7.6Hz,3H),7.21(dd,J=7.8,1.8Hz,2H),7.04(dd,J=8.3,2.0Hz,1H).

[0160] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.2,139.3,137.9,133.3,132.8,131.6,130.5,129.2,128.3,128.1,124.7,96.3.

[0161] MS(EI,70eV)m / z 366,333,286,252,224.

[0162] Example 14

[0163] The 4-bromo-5-(naphth-1-yl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0164]

[0165] 0.1 mmol (E)-3-(dimethylamino)-1-(naphth-1-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product, 4-bromo-5-(naphth-1-yl)-1-phenyl 1H-pyrazole compound, was obtained with a yield of 46% and a purity of 99.9%.

[0166] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0167] 1 H NMR (400MHz, CDCl3, ppm) δ7.95-7.88(m,3H),7.61(d,J=8.2Hz,1H),7.52-7.44(m,3H),7.35(dd,J=7.1,1.1Hz,1H),7.19-7.10(m,5H).

[0168] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ140.8,139.8,139.6,133.4,131.5,130.0,12 9.4,128.7,128.4,127.3,127.0,126.4,126.3,125.3,125.1,123.5,98.0.

[0169] MS(EI,70eV)m / z 348,269,252,241,230.

[0170] Example 15

[0171] The 4-bromo-5-(5-bromo-6-methoxynaphthyl-2-yl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0172]

[0173] 0.1 mmol (E)-3-(dimethylamino)-1-(6-methoxynaphth-2-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-(5-bromo-6-methoxynaphth-2-yl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 84% and a purity of 99.9%.

[0174] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0175] 1 H NMR (400MHz, CDCl3, ppm) δ8.15(d,J=8.9Hz,1H),7.82(d,J=1.7Hz,1H),7.81(s,1H) ,7.78(d,J=9.0Hz,1H),7.32(dd,J=8.9,1.8Hz,1H),7.29-7.23(m,6H),4.02(s,3H).

[0176] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ154.6,141.1,139.8,139.7,132.8,129.8,129.3 ,129.1,129.0,128.6,127.7,126.4,124.6,124.2,114.0,108.4,96.1,56.9.

[0177] MS(EI,70eV)m / z 458,443,415,378,362.

[0178] Example 16

[0179] The 4-bromo-5-([1,1'-biphenyl]-4-yl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0180]

[0181] 0.1 mmol (E)-3-(dimethylamino)-1-([1,1'-biphenyl]-4-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-5-([1,1'-biphenyl]-4-yl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 87% and a purity of 99.9%.

[0182] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0183] 1 H NMR (400MHz, CDCl3, ppm) δ7.80 (s, 1H), 7.65-7.58 (m, 4H), 7.45 (t, J = 7.5Hz, 2H), 7.40-7.27 (m, 8H).

[0184] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.4,141.1,139.98,139.96,139.8,130.3,128.9,128.8,127.7,127.6,127.2,127.0,127.0,124.8,95.8.

[0185] MS(EI,70eV)m / z 374,294,279,267,256.

[0186] Example 17

[0187] The 5-(benzo[d][1,3]dioxacyclopenten-5-yl)-4-bromo-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0188]

[0189] 0.1 mmol (E)-3-(dimethylamino)-1-(benzo[d][1,3]dioxacyclopenten-5-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 5-(benzo[d][1,3]dioxacyclopenten-5-yl)-4-bromo-1-phenyl-1H-pyrazole compound was obtained with a yield of 70% and a purity of 99.9%.

[0190] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0191] 1 H NMR (400MHz, CDCl3, ppm) δ7.73 (s, 1H), 7.34-7.23 (m, 5H), 6.79 (d, J = 8.5Hz, 1H), 6.74 (dd, J = 6.1, 1.7Hz, 2H), 5.98 (s, 2H).

[0192] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ148.1,147.6,140.9,140.1,139.8,128.9,127.6,124.6,124.3,121.9,110.1,108.5,101.4,95.8.

[0193] MS(EI,70eV)m / z 342,313,285,262,233.

[0194] Example 18

[0195] The 4-bromo-5-(5-bromofuran-2-yl)-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0196]

[0197] 0.1 mmol (E)-3-(dimethylamino)-1-(furan-2-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-5-(5-bromofuran-2-yl)-1-phenyl-1H-pyrazole compound was obtained with a yield of 43% and a purity of 99.9%.

[0198] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0199] 1 H NMR (400MHz, CDCl3, ppm) δ7.72 (s, 1H), 7.44-7.39 (m, 3H), 7.33 (dd, J = 7.9, 1.9Hz, 2H), 6.54 (d, J = 3.4Hz, 1H), 6.37 (d, J = 3.4Hz, 1H).

[0200] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ143.5,141.2,139.9,131.1,128.9,128.4,124.7,123.5,114.6,113.0,96.0.

[0201] MS(EI,70eV)m / z 368,287,259,248,233.

[0202] Example 19

[0203] The 2-(4-bromo-1-phenyl-1H-pyrazole-5-yl)pyridine compound obtained in this example has the following structure:

[0204]

[0205] 0.1 mmol (E)-3-(dimethylamino)-1-(pyridin-2-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 2-(4-bromo-1-phenyl-1H-pyrazol-5-yl)pyridine compound was obtained with a yield of 67% and a purity of 99.9%.

[0206] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0207] 1 H NMR (400MHz, CDCl3, ppm) δ8.58(d,J=5.6Hz,1H),7.76(s,1H),7.71(td,J=7.7,1.8Hz,1H),7.43(d,J=7.8Hz,1H),7.31-7.19(m,6H).

[0208] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ149.8,148.0,140.9,139.9,139.3,136.3,128.8,127.6,125.5,124.4,123.3,96.3.

[0209] MS(EI,70eV)m / z 299,219,191,179,164.

[0210] Example 20

[0211] The 4-bromo-5-isopropyl-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0212]

[0213] 0.1 mmol (E)-3-(dimethylamino)-1-isopropyl-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-5-isopropyl-1-phenyl-1H-pyrazole compound was obtained with a yield of 70% and a purity of 99.9%.

[0214] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0215] 1 H NMR (400MHz, CDCl3, ppm) δ7.55 (s, 1H), 7.51-7.42 (m, 3H), 7.37-7.32 (m, 2H), 3.10 (p, J = 7.1Hz, 1H), 1.34 (d, J = 7.1Hz, 6H).

[0216] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ145.0,141.2,139.6,129.1,128.7,126.2,92.0,26.1,20.4.

[0217] MS(EI,70eV)m / z 264,249,235,185,169.

[0218] Example 21

[0219] The 4-bromo-5-cyclopropyl-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0220]

[0221] 0.1 mmol (E)-3-(dimethylamino)-1-cyclopropyl-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-5-cyclopropyl-1-phenyl-1H-pyrazole compound was obtained with a yield of 76% and a purity of 99.9%.

[0222] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0223] 1 H NMR (400MHz, CDCl3, ppm) δ7.56 (s, 1H), 7.52 (d, J = 7.2Hz, 2H), 7.46 (t, J = 7.6Hz, 2H), 7.38 (t,J=7.2Hz,1H),1.77(ddd,J=8.4,5.4,3.1Hz,1H),0.91-0.85(m,2H),0.74-0.69(m,2H).

[0224] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ140.5,140.4,139.8,128.8,127.8,124.7,95.5,7.0,6.5.

[0225] MS(EI,70eV)m / z 262,247,236,222,183.

[0226] Example 22

[0227] The 5-((3r,5r,7r)-adamantane-1-yl)-4-bromo-1-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0228]

[0229] 0.1 mmol (E)-3-(dimethylamino)-1-((3r,5r,7r)-adamantane-1-yl)-2-propen-1-one, 0.2 mmol phenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 5-((3r,5r,7r)-adamantane-1-yl)-4-bromo-1-phenyl-1H-pyrazole compound was obtained with a yield of 66% and a purity of 99.9%.

[0230] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0231] 1 H NMR (400MHz, CDCl3, ppm) δ7.52 (s, 1H), 7.43 (d, J = 7.2Hz, 3H), 7.30 (dd, J = 7.9, 1.7Hz, 2H), 2.00 (d, J = 2.9Hz, 6H), 1.92 (s, 3H), 1.62 (s, 6H).

[0232] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ146.8,143.5,141.9,129.2,128.5,128.3,92.1,40.8,36.4,36.2,28.4.

[0233] MS(EI,70eV)m / z 356,315,301,287,277.

[0234] Example 23

[0235] The 4-bromo-1-(4-fluorophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0236]

[0237] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-fluorophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(4-fluorophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 83% and a purity of 99.9%.

[0238] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0239] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.40-7.34 (m, 3H), 7.29-7.25 (m, 2H), 7.20 (dd, J = 8.9, 4.8Hz, 2H), 6.98 (t, J = 8.5Hz, 2H).

[0240] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ162.8,160.3,141.0,140.4,129.9,129.0128.5,128.2,126.5,126.4,115.9,115.6,95.8.

[0241] MS(EI,70eV)m / z 316,298,236,216,208.

[0242] Example 24

[0243] The 4-bromo-1-(4-chlorophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0244]

[0245] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-chlorophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-1-(4-chlorophenyl)-5-phenyl-1H-pyrazole compound, was obtained with a yield of 56% and a purity of 99.9%.

[0246] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0247] 1 H NMR (400MHz, CDCl3, ppm) δ7.76 (s, 1H), 7.41-7.36 (m, 3H), 7.27 (d, J = 8.6Hz, 4H), 7.16 (d, J = 8.8Hz, 2H).

[0248] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.3,140.4,138.3,133.3,129.9,129.1,129.0,128.6,128.2,125.7,96.2.

[0249] MS(EI,70eV)m / z 332,298,252,226,218.

[0250] Example 25

[0251] The 4-bromo-1-(4-bromophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0252]

[0253] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-bromophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(4-bromophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 81% and a purity of 99.9%.

[0254] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0255] 1 H NMR (400MHz, CDCl3, ppm) δ7.76 (s, 1H), 7.43-7.36 (m, 5H), 7.29-7.25 (m, 2H), 7.10 (d, J = 8.8Hz, 2H).

[0256] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.3,140.3,138.7,131.9,129.9,129.1,128.6,128.1,125.9,121.2,96.2.

[0257] MS(EI,70eV)m / z 378,298,271,258,218.

[0258] Example 26

[0259] The 4-bromo-1-(4-cyanophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0260]

[0261] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-cyanophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(4-cyanophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 75% and a purity of 99.9%.

[0262] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0263] 1 H NMR (400MHz, CDCl3, ppm) δ7.77 (s, 1H), 7.55 (d, J = 8.7Hz, 2H), 7.43-7.37 (m, 3H), 7.33 (d, J = 8.7Hz, 2H), 7.26 (dd, J = 7.4, 2.2Hz, 2H).

[0264] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ142.7,142.0,140.5,132.7,129.7,129.4,128.7,127.8,124.2,117.8,110.7,97.3.

[0265] MS(EI,70eV)m / z 323,308,271,243,215.

[0266] Example 27

[0267] The 4-bromo-1-(4-trifluoromethylphenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0268]

[0269] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-trifluoromethylphenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(4-trifluoromethylphenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 85% and a purity of 99.9%.

[0270] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0271] 1 H NMR (400MHz, CDCl3, ppm) δ7.78 (s, 1H), 7.62 (d, J = 8.2Hz, 2H), 7.41 (d, J = 8.1Hz, 2H), 7.37-7.30 (m, 3H), 7.20 (dd, J = 7.6, 2.1Hz, 2H).

[0272] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.3,139.4138.9,132.1,130.3,129.1,128.1,125.50,125.47,125.43,125.39,124.8,96.3.

[0273] MS(EI,70eV)m / z 366,347,297,286,260.

[0274] Example 28

[0275] The 4-bromo-1-(4-methoxyphenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0276]

[0277] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-methoxyphenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-1-(4-methoxyphenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 73% and a purity of 99.9%.

[0278] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0279] 1 H NMR (400MHz, CDCl3, ppm) δ7.73 (s, 1H), 7.37-7.33 (m, 3H), 7.29-7.26 (m, 2H), 7.14 (d, J = 9.0Hz, 2H), 6.80 (d, J = 9.0Hz, 2H), 3.76 (s, 3H).

[0280] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ158.8,140.5,140.2,133.0,129.9,128.7,128.4,128.3,126.1,113.9,55.3.

[0281] MS(EI,70eV)m / z 328,313,298,285,248.

[0282] Example 29

[0283] The 4-bromo-1-(3-fluorophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0284]

[0285] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 3-fluorophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(3-fluorophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 86% and a purity of 99.9%.

[0286] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0287] 1 H NMR (400MHz, CDCl3, ppm) δ7.77 (s, 1H), 7.39 (dd, J = 5.1, 1.8Hz, 3H), 7.32-7.26 (m ,2H),7.23(td,J=8.2,6.2Hz,1H),7.03(dt,J=9.6,2.2Hz,1H),7.00-6.94(m,2H).

[0288] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ 163.6, 161.1, 141.3, 140.5, 130.0, 129.9, 129.1, 128.6, 128.1, 120.08, 120.05, 114.6, 114.4, 112.2, 111.9, 96.3.

[0289] MS(EI,70eV)m / z 316,236,216,208,198.

[0290] Example 30

[0291] The 4-bromo-1-(3-nitrophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0292]

[0293] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 3-nitrophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(3-nitrophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 69% and a purity of 99.9%.

[0294] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0295] 1 H NMR (400MHz, CDCl3, ppm) δ8.16 (t, J=2.1Hz, 1H), 8.12 (ddd, J=8.0, 2.2, 1.2Hz, 1H), 7.81 ( s,1H),7.51(d,J=8.9Hz,1H),7.46(d,J=8.0Hz,1H),7.44-7.40(m,3H),7.31-7.26(m,2H).

[0296] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ148.3,142.0,140.8,140.6,129.9,129.7,129.6,129.0,127.8,122.0,119.3,97.2.

[0297] MS(EI,70eV)m / z 343,326,313,298,271.

[0298] Example 31

[0299] The 4-bromo-1-(4-bromo-3-methoxyphenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0300]

[0301] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 4-bromo-3-methoxyphenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(4-bromo-3-methoxyphenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 34% and a purity of 99.9%.

[0302] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0303] 1 H NMR (400MHz, CDCl3, ppm) δ7.75 (s, 1H), 7.43-7.37 (m, 4H), 7.31-7.26 (m, 2H), 6.78 (d, J = 2.3Hz, 1H), 6.69 (dd, J = 8.5, 2.4Hz, 1H), 3.66 (s, 3H).

[0304] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ155.9,141.2,140.5,139.9,133.1,129.9,129.1,128.7,128.5,117.3,110.5,108.4,96.3,56.1.

[0305] MS(EI,70eV)m / z 408,328,312,299,285.

[0306] Example 32

[0307] The 4-bromo-1-(2-methylphenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0308]

[0309] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 2-methylphenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube and stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(2-methylphenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 88% and a purity of 99.9%.

[0310] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0311] 1 H NMR (400MHz, CDCl3, ppm) δ7.77 (s, 1H), 7.26 (dq, J = 13.6, 3.7, 3.2Hz, 6H), 7.21-7.15 (m, 3H), 1.98 (s, 3H).

[0312] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.4,140.8,139.0,135.3,130.9,129.4,129.1,128.7,128.2,128.1,128.0,126.4,94.0,17.5.

[0313] MS(EI,70eV)m / z 312,297,284,223,218.

[0314] Example 33

[0315] The 4-bromo-1-(2-fluorophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0316]

[0317] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 2-fluorophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-1-(2-fluorophenyl)-5-phenyl-1H-pyrazole compound, was obtained with a yield of 75% and a purity of 99.9%.

[0318] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0319] 1 H NMR (400MHz, CDCl3, ppm) δ7.80 (s, 1H), 7.40 (td, J = 7.7, 1.7Hz, 1H), 7.37-7.25 (m, 6H), 7.18 (t, J = 7.7Hz, 1H), 7.04 (t, J = 9.2Hz, 1H).

[0320] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ157.6,155.1,142.2,141.8,130.5,130.4,129.3,128.9,128.7,128.3,124.6,116.7,116.5,94.9.

[0321] MS(EI,70eV)m / z 316,296,236,217,198.

[0322] Example 34

[0323] The 4-bromo-1-(3,5-dimethylphenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0324]

[0325] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 3,5-dimethylphenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(3,5-dimethylphenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 91% and a purity of 99.9%.

[0326] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0327] 1 H NMR (400MHz, CDCl3, ppm) δ7.73 (s, 1H), 7.38-7.34 (m, 3H), 7.28 (dd, J = 6.6, 3.1Hz, 2H), 6.90 (s, 1H), 6.82 (s, 2H), 2.21 (s, 6H).

[0328] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ140.7,140.3,139.6,138.6,129.9,129.2,128.8,128.6,128.3,122.4,95.4,21.1.

[0329] MS(EI,70eV)m / z 326,312,246,232,219.

[0330] Example 35

[0331] The 4-bromo-1-(3,4-dichlorophenyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0332]

[0333] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 3,4-dichlorophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 4-bromo-1-(3,4-dichlorophenyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 90% and a purity of 99.9%.

[0334] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0335] 1 H NMR (400MHz, CDCl3, ppm) δ7.76 (s, 1H), 7.46 (d, J = 2.5Hz, 1H), 7.42 (dd, J = 5.1, 1 .8Hz,3H),7.31(d,J=8.7Hz,1H),7.30-7.26(m,2H),6.96(dd,J=8.7,2.5Hz,1H).

[0336] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.7,140.6,138.9,133.0,131.6,130.3,129.9,129.4,128.8,127.9,126.2,123.4,96.7.

[0337] MS(EI,70eV)m / z 366,332,286,252,226.

[0338] Example 36

[0339] The 4-bromo-1-(1-naphthyl)-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0340]

[0341] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 1-naphthylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 10:1. The purified target product 4-bromo-1-(1-naphthyl)-5-phenyl-1H-pyrazole compound was obtained with a yield of 85% and a purity of 99.9%.

[0342] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0343] 1 H NMR (400MHz, CDCl3, ppm) δ7.92 (s, 1H), 7.87 (dd, J = 8.8, 5.5Hz, 2H), 7.65-7.60 (m, 1H), 7 .54-7.48(m,2H),7.39-7.34(m,1H),7.26(dd,J=7.3,1.1Hz,1H),7.20(q,J=7.9Hz,5H).

[0344] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ142.5,141.2,136.1,134.0,130.2,129.4,12 9.3,128.7,128.1,128.0,128.0,127.3,126.6,125.6,124.7,122.9,94.4.

[0345] MS(EI,70eV)m / z 348,268,241,230,215.

[0346] Example 37

[0347] The 2-(4-bromo-5-phenyl-1H-pyrazol-1-yl)pyridine compound obtained in this example has the following structure:

[0348]

[0349] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 2-hydrazinopyridine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product 2-(4-bromo-5-phenyl-1H-pyrazol-1-yl)pyridine compound was obtained with a yield of 27% and a purity of 99.9%.

[0350] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0351] 1 H NMR (400MHz, CDCl3, ppm) δ8.32(d,J=3.8Hz,1H),7.79(s,1H),7.72(td,J=7.9,1.9H z,1H),7.40-7.34(m,4H),7.30(dd,J=6.7,3.1Hz,2H),7.20(dd,J=7.4,4.9Hz,1H).

[0352] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ151.9,148.5,141.7,140.8,138.2,129.8,128.9,128.7,128.2,122.7,118.3,97.0.

[0353] MS(EI,70eV)m / z 299,274,248,220,194.

[0354] Example 38

[0355] The 4-bromo-1-benzyl-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0356]

[0357] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol 1-benzylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred under 10 W blue LEDs for 12 h. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target product, 4-bromo-1-benzyl-5-phenyl-1H-pyrazole compound, was obtained with a yield of 62% and a purity of 99.9%.

[0358] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0359] 1 H NMR (400MHz, CDCl3, ppm) δ7.63 (s, 1H), 7.47-7.43 (m, 3H), 7.32-7.24 (m, 5H), 7.01 (dd, J = 7.5, 1.9Hz, 2H), 5.26 (s, 2H).

[0360] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.6,139.8,136.7,129.9,129.3,128.7,128.6,128.3,127.7,127.0,94.0,54.2.

[0361] MS(EI,70eV)m / z 312,299,235,218,204.

[0362] Example 39

[0363] The 4-bromo-5-phenyl-1H-pyrazole compound obtained in this example has the following structure:

[0364]

[0365] 0.1 mmol (E)-3-(dimethylamino)-1-phenyl-2-propen-1-one, 0.2 mmol hydrazine hydrate, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide, and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 5:1. The purified target products were all 4-bromo-5-phenyl-1H-pyrazole compounds with a yield of 58% and a purity of 99.9%.

[0366] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0367] 1 H NMR (400MHz, CDCl3, ppm) δ7.80-7.72 (m, 2H), 7.54 (s, 1H), 7.43 (q, J = 5.8Hz, 3H).

[0368] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ144.3,136.6,129.6,128.8,128.6,127.5,92.1.

[0369] MS(EI,70eV)m / z 222,195,170,142,116.

[0370] Replacing hydrazine hydrate with benzenesulfonyl hydrazine resulted in a target product yield of 18%; replacing hydrazine hydrate with isobutyric acid hydrazine resulted in a target product yield of 25%.

[0371] Application Example 1

[0372] The 4-bromo-1,5-diphenyl-1H-pyrazole obtained in Example 1 was used to prepare 4-(4-fluorophenyl)-1,5-diphenyl-1H-pyrazole compounds. The structural formula of the product is as follows:

[0373]

[0374] 0.1 mmol of 4-bromo-1,5-diphenyl-1H-pyrazole, 0.15 mmol of 4-fluorophenylboronic acid, 20 mol% palladium acetate, 40 mol% triphenylphosphine, 1.6 equivalents of potassium phosphate, and 1 mL of toluene were added to a reaction tube. The mixture was refluxed in an oil bath at 80 °C for 24 hours under a N2 atmosphere. After the reaction was completed, the mixture was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and dichloromethane, with a volume ratio of petroleum ether to dichloromethane of 1:1. The purified target products were all 4-(4-fluorophenyl)-1,5-diphenyl-1H-pyrazole compounds, with a yield of 57% and a purity of 99.9%.

[0375] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0376] 1 H NMR (400MHz, CDCl3, ppm) δ7.88 (s, 1H), 7.33-7.24 (m, 8H), 7.19-7.12 (m, 4H), 6.95 (t, J = 8.8Hz, 2H).

[0377] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ161.6 (d, J = 244.0Hz), 139.8, 139.5, 139.1, 130.3, 129.9, 129.4 (d ,J=8.0Hz),128.8(d,J=4.0Hz),128.7,128.6,128.5,127.2,125.1,121.5,115.3(d,J=21.0Hz).

[0378] MS(EI,70eV)m / z 314,295,286,257,237.

[0379] Application Example 2

[0380] The 4-bromo-5-(4-iodophenyl)-1-phenyl-1H-pyrazole obtained in Example 5 was used to prepare 4-bromo-1-phenyl-5-(4-(phenylethynyl)phenyl)-1H-pyrazole compounds. The structural formula of the product is as follows:

[0381]

[0382] 0.1 mmol of 4-bromo-5-(4-iodophenyl)-1-phenyl-1H-pyrazole, 0.12 mmol of benzyne, 10 mol% cuprous iodide, 5 mol% bis(triphenylphosphine)dichloropalladium, 0.5 mL of triethylamine, and 1 mL of tetrahydrofuran were added to a reaction tube. The mixture was refluxed in an oil bath at 50 °C for 24 hours under a N2 atmosphere. After the reaction was completed, the mixture was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate, with a volume ratio of petroleum ether to ethyl acetate of 10:1. The purified target products were all 4-bromo-1-phenyl-5-(4-(phenylethynyl)phenyl)-1H-pyrazole compounds, with a yield of 89% and a purity of 99.9%.

[0383] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0384] 1 H NMR (400MHz, CDCl3, ppm) δ7.78 (s, 1H), 7.55-7.51 (m, 4H), 7.37-7.24 (m, 10H).

[0385] 13 C{ 1 H}NMR (100MHz, CDCl3, ppm) δ141.2,139.7,131.7,130.0,129.1,128.6,128.5,128.2,127.9,124.8,123.9,122.9,96.1,91.0,88.8.

[0386] MS(EI,70eV)m / z 398,318,291,280,263.

[0387] Example 40

[0388] The 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole compound obtained in this example has the following structure:

[0389]

[0390] 0.1 mmol (E)-3-(dimethylamino)-1-(4-methoxyphenyl)-2-propen-1-one, 0.2 mmol 4-nitrophenylhydrazine, 0.2 mmol carbon tetrabromide, 2 mol% tris(2-phenylpyridine)iridium, 50 mol% tetrabutylammonium bromide and 1 mL acetonitrile were added to a reaction tube. The mixture was stirred for 12 h under 10 W blue LEDs. After the reaction was completed, the product was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 20:1. The purified target products were all 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole compounds with a yield of 81% and a purity of 99.9%.

[0391] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0392] 1 H NMR (400MHz, DMSO-d6) δ8.23(d,J=9.1Hz,2H),8.06(s,1H),7.47(d,J=9.1Hz,2H),7.24(d,J=8.8Hz,2H),7.02(d,J=8.8Hz,2H),3.79(s,3H).

[0393] 13 C{ 1 H}NMR(100MHz,DMSO-d6)δ160.0,145.8,144.2,142.0,140.8,131.3,124.9,124.6,119.5,114.4,96.8,55.3.

[0394] MS(EI,70eV)m / z 371,357,342,315,292.

[0395] Application Example 3

[0396] The 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole obtained in Example 40 was used to prepare 4-(4-bromo-5-(4-methoxyphenyl)-1H-pyrazole-1-yl)aniline compounds. The structural formula of the product is as follows:

[0397]

[0398] 0.1 mmol of 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole, 5 mol% Pd / C, and 1 mL of methanol were added to a reaction tube. The mixture was refluxed in an oil bath at 25 °C for 12 hours under a H2 atmosphere (1.0 atm). After the reaction, the mixture was purified by column chromatography. The eluent used for column chromatography was a mixture of petroleum ether and ethyl acetate in a volume ratio of 10:1. The purified target products were all 4-(4-bromo-5-(4-methoxyphenyl)-1H-pyrazole-1-yl)aniline compounds, with a yield of 49% and a purity of 99.9%.

[0399] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0400] 1 H NMR(400MHz,DMSO-d6)δ7.78(s,1H),7.17(d,J=8.6Hz,2H),6.94(d,J=8.8Hz ,2H),6.86(d,J=8.5Hz,2H),6.49(d,J=8.4Hz,2H),5.33(s,2H),3.75(s,3H).

[0401] 13 C{ 1 H}NMR(100MHz,DMSO-d6)δ159.3,148.6,139.9,139.4,131.2,128.5,126.3,120.4,113.9,113.3,93.6,55.1.

[0402] MS(EI,70eV)m / z 343,328,312,302,264.

[0403] Application Example 4

[0404] The 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole obtained in Example 40 was used to prepare 4-(4-bromo-5-(4-methoxyphenyl)-3-methyl-1H-pyrazole-1-yl)aniline compounds. The structural formula of the product is as follows:

[0405]

[0406] 0.1 mmol of 4-bromo-5-(4-methoxyphenyl)-1-(4-nitrophenyl)-1H-pyrazole, 5 mol% Pd / C, and 1 mL of methanol were added to a reaction tube. The mixture was refluxed in an oil bath at 25 °C for 12 hours under a H2 atmosphere (1.0 atm). After the reaction, the mixture was purified by column chromatography. The eluent used for column chromatography was a mixed solvent of petroleum ether and ethyl acetate, with a volume ratio of petroleum ether to ethyl acetate of 10:1. The purified target products were all 4-(4-bromo-5-(4-methoxyphenyl)-3-methyl-1H-pyrazole-1-yl)aniline compounds, with a yield of 13% and a purity of 99.9%.

[0407] The structure of the obtained product was characterized, and the structural characterization data are as follows:

[0408] 1 H NMR (400MHz, DMSO-d6) δ7.79 (s, 1H), 7.17 (d, J = 8.8Hz, 2H), 6.96-6.92 (m, 4H), 6 .45(d,J=8.8Hz,2H),5.93(d,J=4.8Hz,1H),3.75(s,3H),2.64(d,J=4.5Hz,3H).

[0409] 13 C{ 1 H}NMR(100MHz,DMSO-d6)δ159.3,149.5,139.9,139.4,131.2,128.3,126.3,120.4,113.9,111.0,93.6,55.1,29.6.

[0410] MS(EI,70eV)m / z 357,342,327,315,278.

[0411] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, not all embodiments. People can obtain other embodiments based on the present invention without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing a 1,5-disubstituted-4-bromopyrazole compound, characterized in that, Includes the following steps: An enaminoketone compound, a hydrazine compound, a brominating reagent, a photocatalyst, an additive, and a polar organic solvent were mixed under light conditions to carry out a cyclization and regioselective bromination reaction to obtain 1,5-disubstituted-4-bromopyrazole compounds; the brominating reagent was selected from carbon tetrabromide; the photocatalyst was selected from tris(2-phenylpyridine)iridium; and the additive was selected from tetrabutylammonium bromide. The enaminoketone compounds have the structure shown in Formula I, the hydrazine compounds have the structure shown in Formula II, and the 1,5-disubstituted-4-bromopyrazole compounds have the structure shown in Formula III. Formula I; Formula II; Formula III; Compounds of Formula III are selected from any of the following structural formulas: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , or .

2. The preparation method according to claim 1, characterized in that, The molar ratio of the enamine ketone compound, the hydrazine compound, and carbon tetrabromide is 1:(1~3):(1~3).

3. The preparation method according to claim 1, characterized in that, The cyclization and regioselective bromination reactions were performed at room temperature for 3–24 hours.

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