Chiral n-(4-indolyl)imidazoles or chiral n-(4-indolyl)imidazole salts and uses thereof

Abstract

The application discloses a kind of chiral N -(4-indolyl)imidazole and its N’ Functional imidazole salt derivatives; the application is obtained by chiral resolution N -(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethyl imidazole R a type and S a type isomers, then react with halogenated hydrocarbon, first obtain axially chiral N Chiral nitrogen heterocyclic carbene precursor imidazole salt of arylimidazole skeleton; the chiral N -(4-indolyl)imidazole salt can be applied in asymmetric catalytic reaction as catalyst or ligand.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis and catalytic reaction technology, specifically relating to a class of chiral N-(4-indolyl)imidazolium or chiral N-(4-indolyl)imidazolium salts, and their use as chiral catalysts or chiral ligands in organic synthesis. Background Technology

[0002] Chiral compounds play an irreplaceable role in many fields due to their unique structures. In the pharmaceutical field, drugs with different configurations can have diametrically opposed effects; for example, the R-configuration of thalidomide can relieve morning sickness, while the S-configuration can cause fetal malformations. In agriculture, the R-configuration of pyrethroid pesticides is highly effective against pests and has low toxicity to beneficial insects. In materials science, chiral liquid crystal molecules are the core materials of LCDs. Therefore, synthesizing chiral compounds with specific configurations is crucial. Asymmetric catalysis is the core strategy for constructing chiral molecules, and it has greatly promoted the development of synthetic chemistry, holding an irreplaceable position in modern organic synthesis and fine chemicals.

[0003] Currently, asymmetric catalysis systems mainly utilize transition metal catalysts and small organic molecule catalysts. Transition metal catalysts regulate the stereoselectivity of reactions through different combinations of chiral ligands and metal centers; small organic molecule catalysts construct chiral environments based on their own structures, inducing enantioselective transformations of substrates. Among numerous catalysts, chiral nitrogen-heterocyclic carbenes (NHC) exhibit significant advantages, serving as both ligands and small organic molecule catalysts. They possess advantages such as wide applicability, good chirality control, high stability, and environmental friendliness, making them an important tool for asymmetric synthesis and representing one of the frontiers of modern synthetic chemistry.

[0004] Structurally, NHCs contain three structural units: a nitrogen heterocyclic core, a core substituent, and an N-substituent. They are typically classified into various types based on the core, such as imidazole carbene, imidazole carbene, thiazole carbene, and 1,2,4-triazole carbene. Chiral NHCs can be broadly classified according to the position of the chiral segment into three main types: chiral N-substituents, chiral fused rings, and chiral cores. They can also be classified according to the chiral element, into three types: those containing a chiral center, a chiral axis, and a chiral facet.

[0005] In the field of imidazole carbene research, monodentate imidazole carbenes containing chiral centers are currently the mainstream. In recent years, imidazole carbenes based on chiral 2,6-bis(1-aryl-1-ethyl)aniline, such as 1 (J. Am. Chem. Soc. 2011, 133, 19680-19683), 2 (Angew. Chem. Int. Ed. 2018, 57, 1376-1380), and 3 (Nat. Commun. 2023, 14, 7640) and similar structures, have shown excellent asymmetric induction properties in metal-catalyzed reactions, as reported by the Gawley group, the Shi Shiliang group, and the Cramer group, respectively.

[0006]

[0007] Monodentate imidazole carbenes containing a chiral axis have been rarely reported. The Clavier group recently prepared imidazole carbene metal complexes containing a chiral axis, such as the complex 4-Pd, by chiral chromatography separation of racemic imidazole carbene metal complexes (J. Am. Chem. Soc. 2020, 142, 93-98).

[0008]

[0009] The preparation of the above-mentioned chiral imidazole carbene requires the use of asymmetric catalytic reactions or chiral chromatographic materials, which is costly and limits the synthetic application.

[0010] We recently prepared a class of N-(4-indolyl)imidazolium salts (Chinese Invention Patent, CN 116253721 B, A Class of N-(4-indolyl)-N'-alkylimidazolium Salts and Their Applications), which involve N-(4-indolyl)imidazolium intermediates containing multiple alkyl substituents. Further studies have shown that the carbon-nitrogen bond rotation of the above-mentioned N-(4-indolyl)imidazolium is restricted, and it is actually axially chiral, being a racemic mixture of the two enantiomers Ra and Sa.

[0011] Based on chiral resolution technology, this invention establishes a method for preparing Ra and Sa type enantiomers from racemic N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (5), and further obtains for the first time the chiral nitrogen heterocyclic carbene precursor imidazolium salt with axial chiral N-aryl imidazolium skeleton by reaction with haloalkanes. Summary of the Invention

[0012] This invention provides a class of chiral N-(4-indolyl)imidazolides with the following structural formula: , ; And chiral mono-N-(4-indolyl)imidazolium salts and bis-N-(4-indolyl)imidazolium salts with chiral axes, with the following general chemical structural formulas: , ; In the formula: Y is selected from C7-C 15 arylmethyl, C2-C 15 Functionalized methyl groups, heterocyclic aryl groups, C1-C8 alkyl groups, , ; X - To counteract anions; L is a linker group; Among them, C7-C 15 The arylmethyl group is selected from benzyl, diphenylmethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2,6-dimethylbenzyl, 3,5-dimethylbenzyl, 3,5-di-tert-butylbenzyl, 2,4,6-trimethylbenzyl, 4-fluorobenzyl, 3,4-difluorobenzyl, 3,5-difluorobenzyl, pentafluorobenzyl, 4-chlorobenzyl, 3,5-dichlorobenzyl, 4-bromobenzyl, 3,5-dibromobenzyl, 4-iodobenzyl, 4-cyanobenzyl, 4-nitrobenzyl, 4-trifluoromethylbenzyl, 3,5-di(trifluoromethyl)benzyl, 1-naphthylmethyl, 2-naphthylmethyl, 9-anthramethyl, 2-pyridinemethyl, and 4-pyridinemethyl.

[0013] C2-C 15 The functionalized methyl group is selected from 2-hydroxyethyl, cyanomethyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, isopropoxycarbonylmethyl, (N,N-dimethylamine)carbonylmethyl, (N,N-diethylamine)carbonylmethyl, (1-azacyclobutyl)carbonylmethyl, (1-pyrrolidinyl)carbonylmethyl, (1-piperidinyl)carbonylmethyl, (4-morpholinyl)carbonylmethyl, (N-methylamine)carbonylmethyl, (N-ethylamine)carbonylmethyl, (N-isopropylamine)carbonylmethyl, (N-phenylamine)carbonylmethyl, [N-(2-methylphenyl)amine]carbonylmethyl, N-(2-isopropylphenyl)amine]carbonylmethyl, [N-(3-methylphenyl)amine]carbonylmethyl, [N-( [4-methylphenyl)amine]carbonylmethyl, [N-(2,4-dimethylphenyl)amine]carbonylmethyl, [N-(2,4,6-trimethylphenyl)amine]carbonylmethyl, [N-(2,6-diisopropylphenyl)amine]carbonylmethyl, [N-(4-trifluoromethylphenyl)amine]carbonylmethyl, [N-(3,5-ditrifluoromethylphenyl)amine]carbonylmethyl, [N-(4-fluorophenyl)amine]carbonylmethyl, [N-(4-chlorophenyl)amine]carbonylmethyl, [N-(4-bromophenyl)amine]carbonylmethyl, [N-(4-iodophenyl)amine]carbonylmethyl, [N-(4-cyanophenyl)amine]carbonylmethyl, [N-(4-nitrophenyl)amine]carbonylmethyl.

[0014] The heterocyclic aryl group is selected from 2-pyrimidinyl, 1-methyl-2-imidazolyl, 5-fluoro-2-pyridinyl, 5-chloro-2-pyridinyl, 5-bromo-2-pyridinyl, 2-benzoxazolyl, 2-benzothiazolyl, and 1-methyl-2-benzimidazolyl.

[0015] The C1-C8 alkyl groups are selected from methyl, ethyl, propyl, 2-propyl, cyclopropyl, butyl, 2-butyl, tert-butyl, cyclobutyl, pentyl, 3-pentyl, cyclopentyl, hexyl, cyclohexyl, heptyl, 4-heptyl, and cycloheptyl.

[0016] X - It is selected from perchlorate, fluoroborate, fluorophosphate, fluoride, chloride, bromide, iodide, p-toluenesulfonate, methanesulfonate, trifluoromethanesulfonate, formate, and acetate.

[0017] L is selected from methylene, 1,2-ethylene, 1,3-propylene, 1,4-butylene, and 1,2-phenylenedimethyl.

[0018] The preparation of the above chiral N-(4-indolyl)imidazolium salts involves two steps: The first step is the chiral tartaric acid resolution of the racemic mixture (rac-5) to obtain R. a -5 and S a -5 enantiomers, the racemic version can be synthesized by methods described in the literature (Chinese Invention Patent, CN 116253721 B, A Class of N-(4-indolyl)-N'-alkylimidazolium Salts and Their Applications).

[0019] ; The second step is R a -5 and S a -5 enantiomers react with monohalogenated or dihalogenated hydrocarbons to give the corresponding chiral mono-N-(4-indolyl)imidazolium salt 6 or bis-N-(4-indolyl)imidazolium salt 7. ; In the formula, R is selected from C7-C 15 arylmethyl, C2-C 15 Functionalized methyl groups, monocyclic / fused-ring heterocyclic aryl groups, and C1-C8 alkyl groups.

[0020] Advantages and technical effects of the present invention: This invention obtains the R of N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium by chiral resolution. a Type and S aThe chiral N-heterocyclic carbene precursors, mono-N-(4-indolyl)imidazolium salt 6 and bis-N-(4-indolyl)imidazolium salt 7, with axially chiral N-arylimidazolium skeletons, were obtained for the first time and can be used as catalysts to induce enantioselective transformation of substrates. For example, chiral mono-N-(4-indolyl)imidazolium salt 6 can be used to catalyze the tandem cyclization reaction of cinnamaldehyde and chalcone (Org. Lett. 2013, 15, 1756-1759) to produce enantiomeric enriched products. The chiral imidazoles and imidazole salts provided by this invention are easy to prepare and have good practical value as novel catalysts. Attached Figure Description

[0021] Figure 1 For R a Schematic diagram of the single crystal structure of 5-L-tartrate; Figure 2 For the racemic (A), R of compound 5 a Type (B), S a HPLC analysis results for type (C). Detailed Implementation

[0022] The following is a detailed description of specific embodiments of the technical solution of the present invention, but it does not constitute a limitation on the scope of protection of the present invention. All reagents used in the embodiments of the present invention are commercially available analytical grade reagents. The racemic N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazole in the embodiments was prepared according to the literature method (Chinese Invention Patent, CN116253721 B, A Class of N-(4-indolyl)-N'-alkylimidazole Salts and Their Applications).

[0023] Example 1: Chiral tartaric acid resolution of racemic N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (rac-5)

[0024] 1. Racemic N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (rac-5, 2 mmol) was mixed with L-tartaric acid (1 mmol) to form L-tartaric acid salt solid. A 98% (v / v) aqueous solution of isopropanol was added to the solid, and the solid-liquid mixture was heated to 80°C until the solid was completely dissolved. The mixture was then cooled until the solid precipitated, and the solid and liquid (mother liquor) were separated. The solid was recrystallized again in the same manner, and the solid and liquid (mother liquor) were separated.

[0025] 2. Add ethyl acetate and saturated sodium carbonate aqueous solution to the solid obtained from the second recrystallization, mix well, collect the organic phase, wash the organic phase three times with saturated sodium carbonate aqueous solution, dry it with anhydrous sodium sulfate, and evaporate the solvent to obtain R.a Type Isomeric Samples (R) a -5, er 100:0, chiral HPLC analysis conditions: Chiralpak ® IC column, mobile phase: hexane / isopropanol 90 / 10, flow rate: 1.0 mL / min. [α] D = +8.6 o (c = 10.4 mg / mL in DCM, t = 18.8℃); 3. Neutralize the mother liquor with NaOH until the pH of the solution is 8, then add saturated sodium carbonate aqueous solution and ethyl acetate for extraction. Collect the organic phase, wash the organic phase three times with saturated sodium carbonate aqueous solution, dry it with anhydrous sodium sulfate, and evaporate the solvent to obtain S. a A sample enriched with type I isomers. This sample (2 mmol) was mixed with D-tartaric acid (1 mmol) to form D-tartarate solid. A 98% (v / v) isopropanol aqueous solution was added to the solid, and the solid-liquid mixture was heated to 80°C until the solid was completely dissolved. The mixture was then cooled until solid precipitated, and the solid and liquid (mother liquor) were separated. The solid was recrystallized again in the same manner, and the solid and liquid (mother liquor) were separated. Ethyl acetate and a saturated sodium carbonate aqueous solution were added to the solid obtained from the second recrystallization, and the mixture was mixed thoroughly. The organic phase was collected, washed three times with a saturated sodium carbonate aqueous solution, dried over anhydrous sodium sulfate, and the solvent was evaporated to obtain S. a Type I isomer sample (S) a -5, er 100:0). [α] D = -8.6 o (c = 10.5 mg / mL in DCM, t = 18.7℃); rac-5, R a -5, S a The HPLC analysis results for -5 are shown in the figure. Figure 2 As can be seen from the figure, the rheotype of pure R was successfully extracted. a -5 and S a -5.

[0026] Example 2: Crystal structure of L-tartaric acid N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium salt The solid obtained by recrystallizing rac-5 and L-tartaric acid twice in an isopropanol aqueous solution in Example 1 was recrystallized in acetone to obtain transparent cubic single crystals with large particle sizes. X-ray single-crystal diffraction analysis confirmed that the obtained isomer was R. a Configuration, single crystal composition is R a -5-L-tartaric acid 1:1 salt ( Figure 1 ).

[0027] Example 3: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-benzyl-4,5-dimethylimidazolium salt (R a -6a) ; In a dry 2mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and benzyl bromide (18 μL, 0.15 mmol) was added. The mixture was heated at 80 °C for 2 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6a (46mg, 99%).

[0028] 1 H NMR (600 MHz, CDCl3) δ 10.13 (s, 1H), 7.42-7.39 (m, 2H), 7.37-7.34(m, 2H), 7.33-7.30 (m, 1H), 6.73 (s, 1H), 6.13 (d, J = 15.0 Hz, 1H), 5.78 (d,J = 15.0 Hz, 1H), 3.92 (s, 3H), 2.75 (s, 3H), 2.66 (q, J = 7.8 Hz, 2H), 2.26(s, 3H), 2.05 (s, 3H), 1.88 (s, 3H), 1.53 (s, 3H), 1.13 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.0, 136.6, 135.1, 133.7, 129.3,129.1, 128.7, 128.1, 126.6, 126.0, 125.3, 124.4, 123.6, 120.5, 102.9, 51.2,32.5, 20.3, 17.5, 16.5, 13.9, 9.3, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 26 H 32N3 386.2591, found 386.2593. [α] D = -14.0 o (c = 10.5 mg / mL in DCM, t = 19.2℃). Example 4: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(4-methylbenzyl)-4,5-dimethylimidazolium salt (R a -6b) ; In a dry 2mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 4-methylbenzyl bromide (28 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 2 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6b (42mg, 88%).

[0029] 1 H NMR (600 MHz, CDCl3) δ 9.99 (s, 1H), 7.28 (d, J = 7.8 Hz, 2H), 7.14 (d, J = 7.8 Hz, 2H), 6.72 (s, 1H), 6.03 (d, J = 14.7 Hz, 1H), 5.69 (d, J =14.7 Hz, 1H), 3.91 (s, 3H), 2.74 (s, 3H), 2.65 (q, J = 7.8 Hz, 2H), 2.31 (s,3H), 2.26 (s, 3H), 2.04 (s, 3H), 1.87 (s, 3H), 1.52 (s, 3H), 1.13 (t, J = 7.8Hz, 3H). 13 C NMR { 1H} (151 MHz, CDCl3) δ 142.0, 138.6, 136.4, 135.1, 130.6,129.8, 129.2, 128.1, 126.6, 126.0, 125.3, 124.4, 123.6, 120.5, 102.8, 51.0,32.5, 21.1, 20.3, 17.5, 16.4, 13.9, 9.3, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 27 H 34 N3 400.2753, found 400.2756. [α] D = -17.2 o (c = 10.5 mg / mL in DCM, t = 19.2℃). Example 5: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(3,5-dimethylbenzyl)-4,5-dimethylimidazolium salt (R a -6c) ; In a dry 2mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 3,5-dimethylbenzyl bromide (30 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 2 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a yellow solid product R. a -6c (47mg, 95%).

[0030] 1H NMR (600 MHz, CDCl3) δ 9.99 (s, 1H), 6.93 (s, 1H), 6.90 (s, 2H), 6.73 (s, 1H), 6.07 (d, J = 15.6 Hz, 1H), 5.62 (d, J = 15.6 Hz, 1H), 3.92 (s,3H), 2.75 (s, 3H), 2.67 (m, 2H), 2.27 (s, 6H), 2.25 (s, 3H), 2.06 (s, 3H),1.89 (s, 3H), 1.58 (s, 3H), 1.14 (t, J = 7.5 Hz, 3H). 13 C NMR{ 1 H} (151 MHz, CDCl3) δ 142.0, 138.8, 136.6, 135.1, 133.5,130.2, 129.2, 126.7, 126.0, 125.4, 125.3, 124.4, 123.6, 120.5, 102.8, 51.2,32.5, 21.2, 20.3, 17.5, 16.5, 13.9, 9.2, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 28 H 36 N3 414.2909, found 414.2911. [α] D = +14.4 o (c = 10.6 mg / mL in DCM, t = 18.9℃). Example 6: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(3,5-di-tert-butylbenzyl)-4,5-dimethylimidazolium salt (R a -6d)

[0031] In a dry 2 mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a-5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 3,5-di-tert-butylbenzyl bromide (43 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 4 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6d (55 mg, 95%).

[0032] 1 H NMR (600 MHz, CDCl3) δ 9.96 (s, 1H), 7.36 (t, J = 1.8 Hz, 1H), 7.15 (d, J = 1.8 Hz, 2H), 6.74 (s, 1H), 6.01 (d, J = 15.3 Hz, 1H), 5.75 (d, J =15.3 Hz, 1H), 3.93 (s, 3H), 2.75 (s, 3H), 2.66 (q, J = 7.5 Hz, 2H), 2.26 (s,3H), 2.07 (s, 3H), 1.91 (s, 3H), 1.58 (s, 3H), 1.28 (s, 18H), 1.13 (t, J =7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 151.8, 142.0, 136.7, 135.1, 132.7,129.2, 126.7, 126.0, 125.4, 124.5, 123.6, 122.5, 122.0, 120.6, 102.9, 52.1,34.9, 32.5, 31.4, 20.3, 17.5, 16.5, 14.0, 9.2, 8.8, 8.4. ESI-HRMS [M-Br] + calcd for C 34 H 48 N3 498.3848, found 498.3850. [α] D = -14.2 o (c = 10.3 mg / mL in DCM, t = 19.1℃). Example 7: Bromination (R) aPreparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-pentafluorobenzyl-4,5-dimethylimidazolium salt (R a -6e)

[0033] In a dry 2 mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and pentafluorobenzyl bromide (40 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 3 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6e (42 mg, 76%).

[0034] 1 H NMR (600 MHz, CDCl3) δ 10.15 (s, 1H), 6.74 (s, 1H), 6.44-6.32 (m,2H), 3.94 (s, 3H), 2.77 (s, 3H), 2.68 (q, J = 7.5 Hz, 2H), 2.25 (s, 3H), 2.04(s, 3H), 1.91 (s, 3H), 1.54 (s, 3H), 1.15 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 146.4-144.4 (m), 143.0-141.0 (m), 142.2, 138.9-136.8 (m), 138.1, 135.2, 129.6, 126.0, 125.9, 125.3, 124.3,123.9, 120.1, 108.0-107.6 (m), 102.8, 40.3, 32.6, 20.3, 17.5, 16.4, 13.9,8.6, 8.4, 8.3. ESI-HRMS [M-Br] + calcd for C 26 H 27 N3F5 476.2125, found 476.2126. [α] D = -10.5o (c = 11.3 mg / mL in DCM, t = 19.2℃). Example 8: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(4-bromobenzyl)-4,5-dimethylimidazolium salt (R a -6f)

[0035] In a dry 2 mL pressure-resistant tube, enantiopure (R) was added. a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 4-bromobenzyl bromide (38 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 5 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6f (44mg, 80%).

[0036] 1 H NMR (600 MHz, CDCl3) δ 10.20 (s, 1H), 7.48 (d, J = 8.4 Hz, 2H), 7.38 (d, J = 8.4 Hz, 2H), 6.73 (s, 1H), 6.17 (d, J = 15.0 Hz, 1H), 5.82 (d, J= 15.0 Hz, 1H), 3.92 (s, 3H), 2.75 (s, 3H), 2.66 (q, J = 7.6 Hz, 2H), 2.28(s, 3H), 2.03 (s, 3H), 1.88 (s, 3H), 1.51 (s, 3H), 1.14 (t, J = 7.6 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.1, 136.5, 135.1, 132.9, 132.2,130.1, 129.4, 126.6, 126.0, 125.2, 123.7, 122.9, 120.4, 102.7, 50.3, 32.5,20.3, 17.5, 16.4, 13.9, 9.3, 8.5, 8.3. ESI-HRMS [M-Br] + calcd for C 26 H 31 N3Br 464.1701, found 464.1701. [α] D = -5.3 o (c =12.1 mg / mL in DCM, t = 18.9℃). Example 9: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(4-trifluoromethylbenzyl)-4,5-dimethylimidazolium salt (R a -6g)

[0037] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 4-trifluoromethylbenzyl bromide (35 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 5 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6g (48 mg, 90%).

[0038] 1 H NMR (600 MHz, CDCl3) δ 10.27 (s, 1H), 7.61 (dd, J = 8.4, 11.4 Hz, 4H), 6.73 (s, 1H), 6.34 (d, J = 15.6 Hz, 1H), 6.01 (d, J = 15.6 Hz, 1H), 3.92(s, 3H), 2.75 (s, 3H), 2.66 (q, J = 7.5 Hz, 2H), 2.27 (s, 3H), 2.03 (s, 3H),1.88 (s, 3H), 1.52 (s, 3H), 1.13 (t, J = 7.5 Hz, 3H). 13 C NMR { 1H} (151 MHz, CDCl3) δ 142.1, 137.8, 136.7, 135.2, 130.8 (q,J = 32.7 Hz), 129.5, 128.6, 126.6, 126.0 (q, J=3.5 Hz), 126.0, 125.2, 124.4,123.7, 123.8 (q, J = 272.3 Hz), 120.3, 102.7, 50.3, 32.5, 20.3, 17.5, 16.4,13.9, 9.3, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 27 H 31 N3F3 454.2470, found 454.2471. [α] D = -12.8 o (c =13.7 mg / mL in DCM, t = 18.9℃). Example 10: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(3,5-ditrifluoromethylbenzyl)-4,5-dimethylimidazolium salt (R a -6h)

[0039] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 3,5-ditrifluoromethylbenzyl bromide (46 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 6 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6h (48 mg, 80%).

[0040] 1H NMR (600 MHz, CDCl3) δ 10.43 (s, 1H), 7.86 (s, 1H), 7.84 (s, 2H), 6.76 (d, J = 16.2 Hz, 1H), 6.75 (s, 1H), 6.11 (d, J = 16.2 Hz, 1H), 3.94 (s, 3H), 2.77 (s, 3H), 2.68 (q, J = 7.5 Hz, 2H), 2.25 (s, 3H), 2.05 (s, 3H), 1.94 (s, 3H), 1.59 (s, 3H), 1.15 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.3, 137.3, 136.9, 135.2, 132.6 (q,J = 33.2 Hz), 130.0, 127.6 (d, J = 3.0 Hz), 126.3, 126.1, 125.3, 124.4,124.0, 122.8 (q, J = 273.3 Hz), 122.6 (t, J = 3.7 Hz), 120.2, 102.6, 49.9,32.6, 20.3, 17.6, 16.4, 13.9, 9.2, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 28 H 30 N3F6 522.2344, found 522.2346. [α] D = +2.5 o (c = 5.1 mg / mL in DCM, t = 19.2°C).

[0041] Example 11: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(4-cyanobenzyl)-4,5-dimethylimidazolium salt (R a -6i)

[0042] In a dry 2 mL pressure-resistant tube, enantiopure (R) a)-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 4-cyanobenzyl bromide (30 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 6 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6i (30 mg, 61%).

[0043] 1 H NMR (600 MHz, CDCl3) δ 10.31 (s, 1H), 7.65 (q, J = 8.6 Hz, 4H), 6.73 (s, 1H), 6.39 (d, J = 15.3 Hz, 1H), 6.07 (d, J = 15.3 Hz, 1H), 3.93 (s,3H), 2.75 (s, 3H), 2.66 (q, J = 7.8 Hz, 2H), 2.28 (s, 3H), 2.02 (s, 3H), 1.88(s, 3H), 1.50 (s, 3H), 1.14 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.2, 139.1, 136.7, 135.2, 132.8,129.6, 129.0, 126.6, 126.0, 125.1, 124.3, 123.8, 120.3, 118.1, 112.6, 102.6,50.1, 32.5, 20.3, 17.5, 16.4, 13.9, 9.4, 8.5, 8.4. ESI-HRMS [M-Br] + calcd for C 27 H 31 N4 411.2549, found 411.2550. [α] D = -8.6 o (c = 10.7 mg / mL in DCM, t = 19.2℃). Example 12: Bromination (R) aPreparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(4-nitrobenzyl)-4,5-dimethylimidazolium salt (R a -6j)

[0044] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 4-nitrobenzyl bromide (32 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 10 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a yellow solid product R. a -6j (48 mg, 94%).

[0045] 1 H NMR (600 MHz, CDCl3) δ 10.37 (s, 1H), 8.18 (d, J = 8.4 Hz, 2H), 7.73 (d, J = 8.4 Hz, 2H), 6.73 (s, 1H), 6.50 (d, J = 15.3 Hz, 1H), 6.17 (d, J= 15.3 Hz, 1H), 3.93 (s, 3H), 2.76 (s, 3H), 2.66 (q, J = 7.8 Hz, 2H), 2.29(s, 3H), 2.03 (s, 3H), 1.89 (s, 3H), 1.52 (s, 3H), 1.14 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 147.9, 142.1, 141.3, 136.7, 135.2,129.7, 129.3, 126.7, 126.0, 125.1, 124.3, 124.2, 123.8, 120.2, 102.6, 49.8,32.5, 20.3, 17.5, 16.4, 13.9, 9.4, 8.6, 8.4. ESI-HRMS [M-Br] + calcd for C 26 H 31N4O2 431.2447, found 431.2450. [α] D = -7.7 o (c = 12.7 mg / mL in DCM, t = 19.2℃). Example 13: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(diphenylmethyl)-4,5-dimethylimidazolium salt (R a -6k)

[0046] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and diphenylbromomethane (37 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 10 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6kJ (43 mg, 80%).

[0047] 1 H NMR (600 MHz, CDCl3) δ 8.08 (s, 1H), 7.81 (s, 1H), 7.49 (d, J = 7.2Hz, 2H), 7.40-7.34 (m, 6H), 7.32 (d, J = 7.2 Hz, 2H), 6.12 (s, 1H), 3.83 (s,3H), 2.69 (q, J = 7.5 Hz, 2H), 2.41 (s, 3H), 2.37(s, 3H), 1.93 (s, 3H), 1.78(s, 3H), 1.65 (s, 3H), 1.14 (t, J = 7.5 Hz, 3H). 13 C NMR { 1H} (151 MHz, CDCl3) δ 143.3, 136.7, 135.8, 135.7, 133.4,130.6, 129.8, 129.4, 129.2, 129.1, 129.0, 128.3, 128.1, 64.6, 33.7, 18.6,17.7, 15.4, 13.9, 10.7, 8.9, 8.5. ESI-HRMS [M-Br] + calcd for C 32 H 36 N3 462.2909, found 462.2912. [α] D = -19.3 o (c = 5.8 mg / mL in DCM, t = 19.2℃). Example 14: Chlorination (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(1-naphthylmethyl)-4,5-dimethylimidazolium salt (S a -6l)

[0048] In a dry 2 mL pressure-resistant tube, enantiopure (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 1-naphthylmethyl chloride (27 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 6 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product S. a -6l (40 mg, 85%).

[0049] 1H NMR (600 MHz, CDCl3) δ 9.78 (s, 1H), 8.13 (d, J = 8.4 Hz, 1H), 7.85 (dd, J=17.7, 8.1 Hz, 2H), 7.58-7.49 (m, 2H), 7.43-7.35 (m, 2H), 6.70 (s, 1H),6.51 (d, J = 15.6 Hz, 1H), 6.30 (d, J = 15.6 Hz, 1H), 3.89 (s, 3H), 2.73 (s,3H), 2.64 (q, J = 7.5 Hz, 2H), 2.27 (s, 3H), 2.03 (s, 3H), 1.90 (s, 3H), 1.51(s, 3H), 1.11 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.0, 137.0, 135.1, 133.8, 130.6,129.6, 129.3, 129.1, 128.9, 127.3, 127.1, 126.5, 126.4, 125.9, 125.4, 125.2,124.4, 123.6, 122.8, 120.5, 102.9, 49.4, 32.5, 20.3, 17.5, 16.4, 13.9, 9.4,8.6, 8.4. ESI-HRMS [M-Cl] + calcd for C 30 H 34 N3 436.2753, found 436.2753. [α] D = 94.4 o (c = 11.9 mg / mL in DCM, t = 19.3℃). Example 15: Chlorination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(9-anthramethyl)-4,5-dimethylimidazolium salt (R a -6m)

[0050] In a dry 2 mL pressure-resistant tube, enantiopure (R) a)-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 9-anthramethyl chloride (34 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 12 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a yellow solid product R. a -6m (32 mg, 61%).

[0051] 1 H NMR (600 MHz, CDCl3) δ 8.47 (s, 1H), 8.45-8.40 (m, 3H), 7.98 (d, J= 8.4 Hz, 2H), 7.62-7.59 (m, 2H), 7.49-7.46 (m, 2H), 6.91 (d, J = 15.6 Hz,1H), 6.75 (d, J = 15.6 Hz, 1H), 6.62 (s, 1H), 3.83 (s, 3H), 2.66 (s, 3H),2.57 (q, J = 7.5 Hz, 2H), 2.44 (s, 3H), 1.90 (s, 3H), 1.87 (s, 3H), 1.31 (s,3H), 1.04 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.0, 134.9, 134.5, 131.2, 130.9,130.3, 129.5, 129.4, 128.4, 128.0, 125.8, 125.5, 125.4, 124.2, 123.6, 123.2,121.9, 120.4, 102.9, 45.5, 32.5, 20.2, 17.4, 16.3, 13.9, 10.2, 8.4. ESI-HRMS [M-Cl] + calcd for C 34 H 36 N3 486.2909, found 486.2912 [α] D = -63.2 o (c = 8.9 mg / mL in DCM, t = 19.0℃). Example 16: Chlorination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(2-pyridylmethyl)-4,5-dimethylimidazolium salt (R a -6n)

[0052] In a dry 2 mL pressure-resistant tube, enantiomeric N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R... a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-pyridinemethyl chloride hydrochloride (25 mg, 0.15 mmol) and N,N-diisopropylethylamine (20 mg, 0.15 mmol) were added. The mixture was heated at 80 °C for 12 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether. The solid was dissolved in dichloromethane, washed with saturated sodium chloride aqueous solution, dried over anhydrous sodium sulfate, and the solvent was evaporated to give a white solid product R. a -6n (36mg, 85%).

[0053] 1 H NMR (600 MHz, CDCl3) δ 10.00 (s, 1H), 8.44 (d, J = 4.2 Hz, 1H), 7.91 (d, J = 7.8 Hz, 1H), 7.71 (td, J = 7.5, 1.8 Hz, 1H), 7.21 (dd, J = 7.6,4.8 Hz, 1H), 6.71 (s, 1H), 6.31 (d, J = 15.3 Hz, 1H), 5.90 (d, J = 15.3 Hz,1H), 3.90 (s, 3H), 2.74 (s, 3H), 2.64 (q, J = 7.5 Hz, 2H), 2.38 (s, 3H), 2.02(s, 3H), 1.90 (s, 3H), 1.47 (s, 3H), 1.11 (t, J = 7.5 Hz, 3H). 13 C NMR { 1H} (151 MHz, CDCl3) δ 153.7, 149.2, 141.9, 137.4, 137.2,135.1, 128.5, 127.1, 125.9, 125.3, 124.6, 123.7, 123.5, 123.3, 120.7, 103.2,51.7, 32.5, 20.3, 17.5, 16.2, 13.9, 9.2, 8.4, 8.2. ESI-HRMS [M-Cl] + calcd for C 25 H 31 N4 387.2549, found 387.2553. [α] D = 29.0 o (c = 2.2 mg / mL in DCM, t = 19.0℃). Example 17: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(2-hydroxyethyl)-4,5-dimethylimidazolium salt (R a -6o)

[0054] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-bromoethanol (19 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 12 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6o (27 mg, 65%).

[0055] 1H NMR (600 MHz, CDCl3) δ 9.31 (s, 1H), 6.73 (s, 1H), 4.83-4.77 (m, 1H), 4.70-4.64 (m, 1H), 4.03-3.98 (m, 1H), 3.97-3.93 (m, 1H), 3.93 (s, 3H), 2.76 (s, 3H), 2.67 (q, J = 7.8 Hz, 2H), 2.40 (s, 3H), 2.01 (s, 3H), 1.94 (s, 3H), 1.56 (s, 3H), 1.13 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.1, 136.6, 135.1, 129.0, 125.9,125.8, 125.2, 124.6, 123.7, 120.4, 103.2, 59.2, 49.1, 32.5, 20.3, 17.5, 16.3,13.9, 8.8, 8.4, 8.3. ESI-HRMS [M-Br] + calcd for C 21 H 30 N3O 340.2389, found 340.2393. [α] D = -21.9 o (c = 8.4 mg / mL in DCM, t = 19.1℃). Example 18: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-ethoxycarbonylmethyl-4,5-dimethylimidazolium salt (R a -6p)

[0056] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a-5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and ethyl bromoethyl (25 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 2 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6p (46 mg, 99%).

[0057] 1 H NMR (600 MHz, CDCl3) δ 10.00 (s, 1H), 6.73 (s, 1H), 6.10 (d, J =18.0 Hz, 1H), 5.52 (d, J = 18.0 Hz, 1H), 4.28 (q, J = 7.2 Hz, 2H), 3.93 (s,3H), 2.76 (s, 3H), 2.67 (q, J = 7.8 Hz, 2H), 2.28 (s, 3H), 2.05 (s, 3H), 1.94(s, 3H), 1.62 (s, 3H), 1.32 (t, J = 7.2 Hz, 3H), 1.13 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 166.5, 142.0, 137.8, 135.1, 128.7,126.5, 125.9, 125.3, 124.5, 123.7, 120.4, 103.2, 62.7, 48.4, 32.5, 20.3,17.5, 16.4, 14.1, 14.0, 8.6, 8.4, 8.3. ESI-HRMS [M-Br] + calcd for C 23 H 32 N3O2 382.2489, found 382.2488. [α] D = -13.8 o (c = 10.4 mg / mL in DCM, t = 19.1℃). Example 19: Chlorination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-[N-(2,4-dimethylphenyl)amino]carbonylmethyl-4,5-dimethylimidazolium salt (R a -6q)

[0058] In a dry 2mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chloro-N-(2,4-dimethylphenyl)acetamide (30 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 8 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6q (43 mg, 87%).

[0059] 1 H NMR (600 MHz, CDCl3) δ 10.79 (s, 1H), 9.21 (s, 1H), 7.36 (d, J =8.1 Hz, 1H), 6.96 (s, 1H), 6.91 (d, J = 8.1 Hz, 1H), 6.74 (s, 1H), 5.92 (d, J= 15.6 Hz, 1H), 5.71 (d, J = 15.6 Hz, 1H), 3.93 (s, 3H), 2.77 (s, 3H), 2.69-2.63 (m, 2H), 2.53 (s, 3H), 2.36 (s, 3H), 2.24 (s, 3H), 2.00 (s, 3H), 1.94 (s, 3H), 1.55 (s, 3H), 1.13 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 163.7, 142.3, 135.8, 135.4, 135.1,132.6, 132.2, 131.2, 128.9, 128.1, 126.5, 125.8, 125.1, 124.6, 124.5, 123.8,120.3, 103.1, 50.1, 32.5, 20.9, 20.3, 18.7, 17.5, 16.1, 13.9, 9.1, 8.4, 8.3. ESI-HRMS [M-Cl] + calcd for C 29 H 37N4O 457.2967, found 457.2970. [α] D = -21.7 o (c = 10.1 mg / mL in DCM, t = 19.1℃). Example 20: Chlorination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-[N-(2,4,6-trimethylphenyl)amino]carbonylmethyl-4,5-dimethylimidazolium salt (R a -6r)

[0060] In a dry 2mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chloro-N-(2,4,6-trimethylphenyl)acetamide (32 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 8 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6r (47 mg, 94%).

[0061] 1 H NMR (600 MHz, CDCl3) δ 10.72 (s, 1H), 9.21 (s, 1H), 6.81 (s, 2H), 6.74 (s, 1H), 5.82-5.75 (m, 2H), 3.93 (s, 3H), 2.77 (s, 3H), 2.69-2.63 (m,2H), 2.54 (s, 3H), 2.21 (s, 6H), 2.20 (s, 3H), 2.06 (s, 3H), 2.00 (s, 3H),1.94 (s, 3H), 1.13 (t, J = 7.8 Hz, 3H). 13 C NMR{ 1H} (151 MHz, CDCl3) δ 163.6, 142.2, 136.5, 135.8, 135.1,134.8, 131.0, 128.9, 128.6, 128.0, 125.8, 125.1, 124.5, 123.8, 120.3, 103.1,49.8, 32.5, 20.8, 20.3, 18.6, 17.5, 16.1, 13.9, 9.1, 8.5, 8.4. ESI-HRMS [M-Cl] + calcd for C 30 H 39 N4O 471.3124, found 471.3128. [α] D = -32.9 o (c = 10.1 mg / mL in DCM, t = 19.0℃). Example 21: Chlorination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-[N-(2-isopropylphenyl)amino]carbonylmethyl-4,5-dimethylimidazolium salt (R a -6s)

[0062] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chloro-N-(2-isopropylphenyl)acetamide (32 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 8 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6s (45mg, 87%).

[0063] 1H NMR (600 MHz, CDCl3) δ 10.96 (s, 1H), 9.20 (s, 1H), 7.36 (d, J =7.5 Hz, 1H), 7.27 (d, J = 7.5 Hz, 1H), 7.15 (t, J = 7.2 Hz, 1H), 7.10 (t, J =7.2 Hz, 1H), 6.74 (s, 1H), 5.95 (d, J = 15.6 Hz, 1H), 5.76 (d, J = 15.6 Hz,1H), 3.93 (s, 3H), 3.48 (hept, J = 7.5 Hz, 1H), 2.76 (s, 3H), 2.69-2.62 (m,2H), 2.52 (s, 3H), 2.00 (s, 3H), 1.94 (s, 3H), 1.55 (s, 3H), 1.21 (t, J = 6.6Hz, 6H), 1.12 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 164.4, 143.5, 142.2, 135.8, 135.1,133.6, 128.9, 128.1, 126.6, 126.1, 125.8, 125.8, 125.7, 125.1, 124.5, 123.8,120.3, 103.1, 50.1, 32.5, 27.8, 23.5, 23.4, 20.3, 17.5, 16.1, 13.9, 9.1, 8.4,8.3. ESI-HRMS [M-Cl] + calcd for C 30 H 39 N4O 471.3124, found 471.3127. [α] D = -25.3 o (c = 10.7 mg / mL in DCM, t = 19.0℃). Example 22: Chlorination (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-[N-(2,6-diisopropylphenyl)amino]carbonylmethyl-4,5-dimethylimidazolium salt (S a -6t)

[0064] In a dry 2mL pressure-resistant tube, add (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chloro-N-(2,6-diisopropylphenyl)acetamide (38 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 8 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product S. a -6t (45mg, 81%).

[0065] 1 H NMR (600 MHz, CDCl3) δ 10.84 (s, 1H), 9.18 (s, 1H), 7.23 (t, J =7.8 Hz, 1H), 7.12 (d, J = 7.8 Hz, 2H), 6.75 (s, 1H), 5.93 (d, J = 15.6 Hz,1H), 5.78 (d, J = 15.6 Hz, 1H), 3.94 (s, 3H), 3.16 (bs, 2H), 2.77 (s, 3H),2.71 – 2.63 (m, 2H), 2.56 (s, 3H), 2.01 (s, 3H), 1.97 (bs, 3H), 1.96 (s, 3H), 1.22 (bs, 6H), 1.18 – 1.10 (m, 9H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 164.6, 145.9, 142.3, 135.6, 135.1,131.1, 129.0, 128.2, 128.1, 125.8, 125.0, 124.5, 123.9, 123.2, 120.3, 103.1,49.8, 32.6, 28.7, 24.1, 24.2, 23.5, 20.3, 17.5, 16.1, 13.9, 9.1, 8.5, 8.3. ESI-HRMS [M-Cl] + calcd for C 33 H 45 N4O 513.3593, found 513.3593. [α] D = -42.1 o (c = 11.7 mg / mL in DCM, t = 19.2℃). Example 23: Chlorination (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-[N-(3,5-ditrifluoromethylphenyl)amino]carbonylmethyl-4,5-dimethylimidazolium salt (S a -6u)

[0066] In a dry 2 mL pressure-resistant tube, enantiopure (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chloro-N-(3,5-ditrifluoromethylphenyl)acetamide (46 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 8 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product S. a -6u (43 mg, 87%).

[0067] 1 H NMR (600 MHz, CDCl3) δ 12.46 (s, 1H), 9.50 (bs, 1H), 8.23 ​​(s, 2H), 7.45 (s, 1H), 6.77 (s, 1H), 6.03-5.86 (m, 2H), 3.95 (s, 3H), 2.79 (s, 3H),2.73-2.66 (m, 2H), 2.41 (s, 3H), 2.06 (s, 3H), 1.96 (s, 3H), 1.61 (s, 3H),1.15 (t, J = 7.5 Hz, 3H). 13 C NMR{ 1H} (151 MHz, CDCl3) δ 164.0, 142.3, 139.8, 136.6, 135.2,131.6 (q, J = 33.2 Hz), 129.0, 127.7, 125.8, 125.2, 124.5, 123.8, 123.1 (q, J= 272.8 Hz), 120.4, 119.3 (bs), 117.1 (bs), 103.3, 50.3, 32.6, 20.4, 17.5,16.1, 13.9, 8.9, 8.5, 8.3. ESI-HRMS [M-Cl] + calcd for C 29 H 31 N4OF6 566.2402, found 566.2399. [α] D = 28.7 o (c = 15.2 mg / mL in DCM, t = 19.1℃). Example 24: Bromination (R) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(2-pyrimidinyl)-4,5-dimethylimidazolium salt (R a -6v)

[0068] In a dry 2 mL pressure-resistant tube, enantiopure (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-bromopyrimidine (24 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 10 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product R. a -6v (32 mg, 70%).

[0069] 1H NMR (600 MHz, CDCl3) δ 9.58 (s, 1H), 9.02 (d, J =5.1 Hz, 2H), 7.79 (t, J = 5.1 Hz, 1H), 6.80 (s, 1H), 3.96 (s, 3H), 2.85 (s, 3H), 2.79 (s, 3H), 2.70 (q, J = 7.5 Hz, 2H), 2.14 (s, 3H), 2.09 (s, 3H), 1.61 (s, 3H), 1.15 (t,J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 159.9, 153.6, 142.7, 135.2, 135.1,131.6, 127.7, 126.0, 125.0, 124.4, 124.1, 123.0, 119.8, 102.5, 32.7, 20.4,17.5, 16.5, 14.0, 12.3, 8.6, 8.5. ESI-HRMS [M-Br] + calcd for C 23 H 28 N5 374.2345, found 374.2348. [α] D = -42.8 o (c = 4.1 mg / mL in DCM, t = 19.2℃). Example 25: Chlorination (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(2-benzoxazolyl)-4,5-dimethylimidazolium salt (S a -6w)

[0070] In a dry 2mL pressure-resistant tube, add (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a-5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chlorobenzoxazole (23 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 12 h. After the reaction was completed, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate and petroleum ether and dried to give a white solid product (23 mg, 51%).

[0071] 1 H NMR (600 MHz, CDCl3) δ 11.24 (s, 1H), 7.79 (bd, J = 7.2 Hz, 2H), 7.48-7.42 (m, 2H), 6.80 (s, 1H), 3.95 (s, 3H), 2.86 (s, 3H), 2.78 (s, 3H), 2.68 (q, J = 7.5 Hz, 2H), 2.23 (s, 3H), 2.06 (s, 3H), 1.64 (s, 3H), 1.15 (t,J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 149.4, 149.0, 142.3, 139.8, 138.5,135.2, 131.0, 126.9, 126.6, 126.3, 125.9, 125.6, 124.2, 124.0, 120.6, 119.7,112.1, 102.5, 32.6, 20.4, 17.6, 16.8, 14.0, 11.2, 8.7, 8.5. ESI-HRMS [M-Cl] + calcd for C 26 H 29 N4O 413.2341, found 413.2342. [α] D =45.8 o (c = 11.2 mg / mL in DCM, t = 19.3℃). Example 26: Chlorination (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-(2-benzothiazolyl)-4,5-dimethylimidazolium salt (S a -6x)

[0072] In a dry 2 mL pressure-resistant tube, enantiopure (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and 2-chlorobenzothiazole (26 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 12 h. After the reaction was complete, the mixture was cooled to room temperature and evaporated to dryness to obtain the crude product. The crude product was then subjected to silica gel column chromatography (DCM / MeOH). Separation at a ratio of 100:1 yielded a transparent oily product S. a -6x (23mg, 50%).

[0073] 1 H NMR (600 MHz, CDCl3) δ 11.13 (s, 1H), 8.04 (d, J = 7.8 Hz, 1H), 7.96 (d, J = 7.8 Hz, 1H), 7.58-7.54 (m, 1H), 7.52-7.48 (m, 1H), 6.77 (s, 1H),3.92 (s, 3H), 2.75 (s, 3H), 2.74 (s, 3H), 2.66 (q, J = 7.8 Hz, 2H), 2.22 (s,3H), 2.05 (s, 3H), 1.63 (s, 3H), 1.13 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 153.1, 149.5, 142.2, 138.2, 138.1,135.1, 134.7, 130.7, 127.3, 127.0, 126.2, 125.5, 124.1, 124.0, 123.7, 122.4,119.8, 102.5, 32.5, 20.4, 17.5, 16.8, 14.0, 11.0, 8.6, 8.5. ESI-HRMS [M-Cl] + calcd for C 26 H 29 N4S 429.2113, found 429.2113. [α] D =20.8 o (c = 3.1 mg / mL in DCM, t = 19.2℃). Example 27: Perchloric acid (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-methyl-4,5-dimethylimidazolium salt (S a -6y)

[0074] In a dry 2 mL pressure-resistant tube, enantiopure (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and iodomethane (22 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 1 h. After the reaction was complete, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate, petroleum ether, and a 2M sodium perchlorate solution in methanol, and dried to give a white solid product S. a -6y (41 mg, 99%).

[0075] 1 H NMR (600 MHz, CDCl3) δ 8.94 (s, 1H), 6.74 (s, 1H), 4.09 (s, 3H), 3.94 (s, 3H), 2.77 (s, 3H), 2.68 (q, J = 7.8 Hz, 2H), 2.40 (s, 3H), 2.04 (s, 3H), 1.93 (s, 3H), 1.53 (s, 3H), 1.14 (t, J = 7.8 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.1, 135.7, 135.1, 129.2, 127.0,126.0, 125.5, 124.5, 123.8, 120.3, 102.9, 34.6, 32.6, 20.4, 17.5, 16.3, 14.0,8.7, 8.5, 8.3. ESI-HRMS [M-ClO4] + calcd for C 20 H 28 N3 310.2283, found 310.2287. [α] D = 30.0 o(c = 20.5 mg / mL in DCM, t = 19.3℃). Example 28: Perchloric acid (S) a Preparation of )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-isopropyl-4,5-dimethylimidazolium salt (S a -6z)

[0076] In a dry 2 mL pressure-resistant tube, add (S) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (S a -5, 30 mg, 0.1 mmol) was dissolved in ethyl acetate (0.1 mL), and iodoisopropane (26 mg, 0.15 mmol) was added. The mixture was heated at 80 °C for 10 h. After the reaction was completed, the mixture was cooled to room temperature, the solvent was evaporated, and the solid was repeatedly washed with ethyl acetate, petroleum ether, and a methanol-water solution of 2 M sodium perchlorate. The solid was dried to give a white solid product (35 mg, 80%).

[0077] 1 H NMR (600 MHz, CDCl3) δ 8.49 (s, 1H), 6.76 (s, 1H), 4.80 (hept, J =7.2 Hz, 1H), 3.94 (s, 3H), 2.77 (s, 3H), 2.71-2.65 (m, 2H), 2.48 (s, 3H), 2.05 (s, 3H), 1.95 (s, 3H), 1.70 (d, J = 7.2 Hz, 3H), 1.65 (d, J = 7.2 Hz, 3H), 1.50 (s, 3H), 1.15 (t, J = 7.5 Hz, 3H). 13 C NMR { 1 H} (151 MHz, CDCl3) δ 142.2, 135.1, 132.3, 130.0, 126.8,126.0, 125.5, 124.4, 123.8, 120.4, 102.6, 51.3, 32.6, 22.8, 22.4, 20.4, 17.5,16.2, 14.0, 9.1, 8.4, 8.1. ESI-HRMS [M-ClO4] + calcd for C 22 H 32N3 338.2596, found 338.2598. [α] D = 78.6 o (c = 10.7 mg / mL in DCM, t = 19.3℃). Example 29: Chloride 1,1'-[1,2-phenylenebismethylene]bis[(R a Preparation of [N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium] salt (R) a ,R a -7a)

[0078] In a dry 2 mL pressure-resistant tube, place (R) a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium (R a -5, 60 mg, 0.2 mmol) was dissolved in ethyl acetate (0.1 mL), and o-dichlorobenzyl (18 mg, 0.1 mmol) was added. The mixture was heated at 80 °C for 6 h. After the reaction was complete, the mixture was cooled to room temperature and evaporated to dryness to obtain the crude product. The crude product was then subjected to silica gel column chromatography (DCM / MeOH). Separation at a ratio of 40:1 yielded a transparent oily product R. a ,R a -7a (7 mg, 95%).

[0079] 1 H NMR (600 MHz, CDCl3) δ 10.01 (s, 1H), 10.00 (s, 1H), 7.25-7.20 (m,2H), 6.71 (s, 2H), 6.66-6.48 (m, 6H), 3.90 (s, 6H), 2.73 (s, 6H), 2.69-62 (m,4H), 2.45 (s, 6H), 2.05 (s, 3H), 2.04 (s, 3H), 1.96 (s, 6H), 1.66 (s, 3H),1.64 (s, 3H), 1.12 (t, J = 7.5 Hz, 6H). 13 C NMR { 1H} (151 MHz, CDCl3) δ 141.8, 136.7, 134.9, 132.6, 129.1,128.2, 128.0, 125.7, 124.9, 124.5, 124.2, 123.3, 120.5, 102.7, 48.2, 32.3,20.1, 17.3, 16.2, 13.8, 9.2, 8.6, 8.4. ESI-HRMS [M-Cl] + calcd for C 46 H 58 N6Cl 729.4411, found 729.4402. [α] D =111.2 o (c = 12.4 mg / mL in DCM, t = 19.3℃). Example 30: Halogenation (R) a Asymmetric tandem cyclization reaction catalyzed by )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-4,5-dimethylimidazolium salt

[0080] Halogenated compounds (R) are added sequentially to the drying reaction tube. a )-N-(1,3,5,7-tetramethyl-2-ethyl-4-indolyl)-N'-substituted-4,5-dimethylimidazolium salt (0.01 mmol), cinnamaldehyde (S1, 0.1 mmol), and 1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (S2, 0.1 mmol) were added under argon protection with DME (0.2 mL) and DBU (3 μL). The reaction was carried out at room temperature and monitored by TLC. After the reaction was completed, the reaction solution was filtered through diatomaceous earth, washed with ethyl acetate, and the filtrates were combined and washed three times with saturated sodium chloride aqueous solution. The organic phase was dried over anhydrous sodium sulfate and concentrated to obtain the crude product. The crude product was purified by silica gel column chromatography (PE / EA 20:1). The er value was determined by chiral HPLC. ® IM column, mobile phase n-hexane / isopropanol 90 / 10, flow rate 1.0 mL / min.

[0081] .

Claims

1. A chiral N-(4-indolyl)imidazolium with the following structural formula: ， 。 2. Chiral N-(4-indolyl)imidazolium salts with the following structural formula: ， ； In the formula: Y is selected from C7-C 15 arylmethyl, C2-C 15 Functionalized methyl groups, heterocyclic aryl groups, C1-C8 alkyl groups, , ; X - To counteract anions; L is a linker group.

3. The chiral N-(4-indolyl)imidazolium salt according to claim 2, characterized in that: C7-C 15 The arylmethyl group is selected from benzyl, diphenylmethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2,6-dimethylbenzyl, 3,5-dimethylbenzyl, 3,5-di-tert-butylbenzyl, 2,4,6-trimethylbenzyl, 4-fluorobenzyl, 3,4-difluorobenzyl, 3,5-difluorobenzyl, pentafluorobenzyl, 4-chlorobenzyl, 3,5-dichlorobenzyl, 4-bromobenzyl, 3,5-dibromobenzyl, 4-iodobenzyl, 4-cyanobenzyl, 4-nitrobenzyl, 4-trifluoromethylbenzyl, 3,5-di(trifluoromethyl)benzyl, 1-naphthylmethyl, 2-naphthylmethyl, 9-anthramethyl, 2-pyridinemethyl, 4-pyridinemethyl; C2-C 15 The functionalized methyl group is selected from 2-hydroxyethyl, cyanomethyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, isopropoxycarbonylmethyl, (N,N-dimethylamine)carbonylmethyl, (N,N-diethylamine)carbonylmethyl, (1-azacyclobutyl)carbonylmethyl, (1-pyrrolidinyl)carbonylmethyl, (1-piperidinyl)carbonylmethyl, (4-morpholinyl)carbonylmethyl, (N-methylamine)carbonylmethyl, (N-ethylamine)carbonylmethyl, (N-isopropylamine)carbonylmethyl, (N-phenylamine)carbonylmethyl, [N-(2-methylphenyl)amine]carbonylmethyl, N-(2-isopropylphenyl)amine]carbonylmethyl, [N-(3-methylphenyl)amine]carbonylmethyl, [N-( [4-methylphenyl)amine]carbonylmethyl, [N-(2,4-dimethylphenyl)amine]carbonylmethyl, [N-(2,4,6-trimethylphenyl)amine]carbonylmethyl, [N-(2,6-diisopropylphenyl)amine]carbonylmethyl, [N-(4-trifluoromethylphenyl)amine]carbonylmethyl, [N-(3,5-ditrifluoromethylphenyl)amine]carbonylmethyl, [N-(4-fluorophenyl)amine]carbonylmethyl, [N-(4-chlorophenyl)amine]carbonylmethyl, [N-(4-bromophenyl)amine]carbonylmethyl, [N-(4-iodophenyl)amine]carbonylmethyl, [N-(4-cyanophenyl)amine]carbonylmethyl, [N-(4-nitrophenyl)amine]carbonylmethyl; The heterocyclic aryl group is selected from 2-pyrimidinyl, 1-methyl-2-imidazolyl, 5-fluoro-2-pyridinyl, 5-chloro-2-pyridinyl, 5-bromo-2-pyridinyl, 2-benzoxazolyl, 2-benzothiazolyl, and 1-methyl-2-benzimidazolyl. The C1-C8 alkyl groups are selected from methyl, ethyl, propyl, 2-propyl, cyclopropyl, butyl, 2-butyl, tert-butyl, cyclobutyl, pentyl, 3-pentyl, cyclopentyl, hexyl, cyclohexyl, heptyl, 4-heptyl, and cycloheptyl. X - Selected from perchlorate, fluoroborate, fluorophosphate, fluoride, chloride, bromide, iodide, p-toluenesulfonate, methanesulfonate, trifluoromethanesulfonate, formate, and acetate; L is selected from methylene, 1,2-ethylene, 1,3-propylene, 1,4-butylene, and 1,2-phenylenedimethyl.

4. The application of the chiral N-(4-indolyl)imidazolium salt as a catalyst or ligand in asymmetric organic reactions according to claim 3.

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