Preparation method of 1-[2-(1-methylindolyl)]-2-naphthylamine

Abstract

The invention discloses a method for preparing 1-[2-(1-methylindolyl)]-2-naphthylamine, comprising the following steps: adding 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine (0.1 mmol), gold chloride (0.005 mmol), and 1.5 mL of 1,2-dichloroethane to a 10 mL reaction tube, reacting at room temperature, and detecting complete reaction by TLC. After the reaction is completed, the solvent is removed under reduced pressure, and a pure product is obtained by column chromatography. The technical solution of the present invention has the advantages of small catalyst dosage, no need for any additives, smooth reaction in an air atmosphere, no need for inert gas protection, simple operation, mild reaction conditions, few side reactions, moderate solvent boiling point, easy removal, and convenient post-processing.

Description

Technical Field

[0001] The present invention relates to an organic synthesis intermediate, in particular to a preparation method of 1-[2-(1-methylindolyl)]-2-naphthylamine. Background Art

[0002] 1-[2-(1-Methylindolyl)]-2-naphthylamine compounds are important organic synthesis intermediates used in the synthesis of organic optoelectronic materials (CN 108774233 A). The development of simple and efficient methods for synthesizing these compounds is of great significance for the development and research of new materials.

[0003] The preparation methods of 1-[2-(1-methylindolyl)]-2-naphthylamine reported in the literature mainly include:

[0004] Using substituted indole and naphthotriazole derivatives as raw materials, in the presence of rhodium catalyst, with silver hexafluoroantimonate and silver acetate as additives, and chlorobenzene as solvent, the reaction was carried out under nitrogen protection to obtain 1-[2-(1-methylindolyl)]-2-naphthylamine derivatives.

[0005]

[0006] This method requires the use of a large amount of expensive precious metal catalysts and additives, requires nitrogen protection, uses the high-boiling-point solvent chlorobenzene, and has cumbersome post-processing. Summary of the Invention

[0007] The present invention aims to provide a method for preparing 1-[2-(1-methylindolyl)]-2-naphthylamine, which has mild reaction conditions, simple operation, few side reactions and convenient post-processing.

[0008] The technical solution of the present invention is to react a certain amount of 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine, gold chloride, and 1,2-dichloroethane as a solvent at room temperature. After the reaction is complete, the solvent is removed under reduced pressure, and column chromatography is performed to obtain pure 1-[2-(1-methylindolyl)]-2-naphthylamine.

[0009] Preferably, it comprises the following steps: step 1: adding 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine (0.1 mmol), gold chloride (0.005 mmol), and 1.5 mL of 1,2-dichloroethane into a 10 mL reaction tube, and reacting at room temperature; step 2: after the reaction is completed, removing the solvent under reduced pressure, and performing column chromatography to obtain pure 1-[2-(1-methylindolyl)]-2-naphthylamine.

[0010] Preferably, the reaction time in step 1 is 6-24 hours at room temperature.

[0011] The above technical solution has the following beneficial effects: 1. It requires a small amount of catalyst and does not require any additives; 2. The reaction can occur smoothly in an air atmosphere, does not require inert gas protection, and is easy to operate; 3. The solvent has a moderate boiling point, is easy to remove, and is convenient for post-processing; 4. The reaction conditions are mild, the selectivity is good, the side reactions are few, and the product yield is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attachment Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of the product obtained in Example 1.

[0013] Attachment Figure 2 This is the carbon NMR spectrum of the product obtained in Example 1. DETAILED DESCRIPTION

[0014] The following describes the implementation of the present invention through specific embodiments. People skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0015] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the present invention will be more comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present invention. However, those skilled in the art will appreciate that the technical solutions of the present invention may be practiced while omitting one or more of the specific details, or that other methods, components, devices, steps, etc. may be employed. In other cases, well-known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present invention.

[0016] Example:

[0017] Step 1: Add 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine (0.1 mmol), gold chloride (0.005 mmol), and 1.5 mL of 1,2-dichloroethane to a 10 mL reaction tube and react at room temperature for 12 hours;

[0018] Step 2: After the reaction is completed, the solvent is removed under reduced pressure and column chromatography is performed to obtain pure 1-[2-(1-methylindolyl)]-2-naphthylamine, the molecular formula of which is:

[0019]

[0020] Yield: 81%; the product is a white solid; the H NMR spectrum of the product is as follows Figure 1Shown: (DMSO-d6, 400 MHz) (δ, ppm): 7.81-7.71 (m, 2H), 7.64 (d, J = 7.6 Hz, 1H), 7.51 (d, J = 8.0 Hz, 1H), 7.26-7.17 (m, 3H), 7.17-7.08 (m, 2H), 7.06 (d, J = 8.4 Hz, 1H), 6.51 (s, 1H), 5.16 (s, 2H), 3.39 (s, 3H).

[0021] C NMR spectra such as Figure 2 Shown: (DMSO-d6, 100 MHz) (δ, ppm): 144.1, 137.9, 135.5, 134.9, 130.4, 128.5, 128.1, 127.8, 127.1, 124.1, 122.5, 121.5, 120.7, 119.7, 117.8, 109.7, 109.4, 103.0, 30.1.

[0022] Infrared spectrum (KBr, ν, cm-1): 3469, 2925, 1621, 1507, 1464, 1388, 1309, 816, 790, 750.

[0023] High-resolution mass spectrometry (ESI) m / z calcd for C19H16N2(M+H)+:273.1392; Found:273.1388.

[0024] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A method for preparing 1-[2-(1-methylindolyl)]-2-naphthylamine, characterized in that: It includes the following steps: Step 1: reacting a certain amount of 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine, gold chloride and solvent 1,2-dichloroethane at room temperature; Step 2: after the reaction is completed, removing the solvent under reduced pressure and performing column chromatography to obtain pure 1-[2-(1-methylindolyl)]-2-naphthylamine.

2. A method for preparing 1-[2-(1-methylindolyl)]-2-naphthylamine, characterized in that: The method comprises the following steps: step 1: adding 0.1 mmol of 1-[(2-methylaminophenyl)ethynyl]-2-naphthylamine, 0.005 mmol of gold chloride, and 1.5 mL of 1,2-dichloroethane into a 10 mL reaction tube, and reacting at room temperature; step 2: after the reaction is completed, removing the solvent under reduced pressure, and performing column chromatography to obtain pure 1-[2-(1-methylindolyl)]-2-naphthylamine.

3. The method for preparing 1-[2-(1-methylindolyl)]-2-naphthylamine according to claim 1 or 2, characterized in that The reaction time in step 1 is 6-24 hours at room temperature.

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