CN109111351B

CN109111351B - Synthesis method of asymmetric 9-alkoxy phenanthrene dimer

Info

Publication number: CN109111351B
Application number: CN201710529926.3A
Authority: CN
Inventors: 王奇峰; 李锋
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2017-06-23
Filing date: 2017-06-23
Publication date: 2021-08-20
Anticipated expiration: 2037-06-23
Also published as: CN109111351A

Abstract

A synthetic method of asymmetric 9-alkoxy phenanthrene dimer belongs to the technical field of organic synthetic chemistry. The invention provides a synthesis method of 9-alkoxy phenanthrene dimer with asymmetric structure through researching self cross coupling reaction of 9-phenanthrene methyl ether under various oxidants. In the method, the inventor adopts persulfate as an oxidant to realize a direct construction method of C-C bonds at 1 position and 9 ' position of 9-alkoxy phenanthrene under a specific acidic condition, and obtains a series of 9, 10 ' -dialkoxy-1, 9 ' -biphenyl phenanthrene compounds. The invention technically provides a synthesis method of an asymmetric 9-alkoxy phenanthrene dimer, and the compound can be used for the design and synthesis of novel chiral ligands and photoelectric materials. The yield of the 9, 10 '-dialkoxy-1, 9' -biphenyl product is 53-64 percent. The nuclear magnetic resonance spectrogram confirms the structure of the product and determines that the purity of the product is more than 95 percent.

Description

Synthesis method of asymmetric 9-alkoxy phenanthrene dimer

Technical Field

The invention belongs to the technical field of organic synthesis, and particularly relates to a synthetic method of an asymmetric 9-alkoxy phenanthrene dimer.

Background

Polycyclic aromatic hydrocarbon phenanthrene has unique planar structure, rigid structure and conjugated system, and the properties of polycyclic aromatic hydrocarbon phenanthrene enable polycyclic aromatic hydrocarbon phenanthrene to have important research values in the fields of luminescent materials, asymmetric synthesis and the like. Through literature studies, the applicant has noted that the reaction site of 9-hydroxy phenanthrene and its derivatives usually occurs at the 10-position, which is closely related to the structural features of phenanthrene itself. Under the decisive action of the reaction property, the 9-hydroxy phenanthrene and the derivatives thereof usually undergo homocoupling reaction at the 10-position in the reaction for synthesizing the dimer, so that the 9-hydroxy phenanthrene dimer with a completely symmetrical structure is obtained, as shown in formula 1.

Since the active site of the 9-hydroxy phenanthrene derivative is the 10-position, the difficulty of further derivatization on an aromatic ring is very high after the coupling through self symmetry, so that the compound is not only applied to asymmetric synthesis, but also difficult to obtain more types of new materials through further derivatization.

In this context, the applicant has finally found that by studying the reaction of oxidizing agents of different types of oxidizing agents with 9-alkoxyphenanthrene, an asymmetric coupling product of 9-alkoxyphenanthrene can be obtained by oxidative coupling of alkoxyphenanthrene using persulfate in an acidic system. This finding has not been reported in the literature or in the prior art. The compound retains a 10-site active site, can be further derived to obtain more types of phenanthrene phenol derivatives, and can also be converted into a large conjugated system with a multi-ring structure for the research of photoelectric materials, so that the compound has important research value and application value.

Disclosure of Invention

The invention aims to provide a synthetic method of an asymmetric 9-alkoxy phenanthrene dimer, which is shown in a formula 2:

the method comprises the following specific steps:

(1) under the protection of nitrogen, 0.2mmol of 9-alkoxyphenanthrene is added into a Schlenk tube, and an appropriate amount of organic solvent is added and stirred to completely dissolve the substrate.

(2) Persulfate (1.0-10.0equiv.) was added at 0 deg.C, and trifluoroacetic acid was added by injection, maintaining a nitrogen atmosphere.

(3) Reacting for 1-3 h under the stirring condition, and detecting that the 9-alkoxy phenanthrene completely disappears by thin-layer chromatography.

(4) Adding equal volume of water and Na into the reaction system₂CO₃Neutralization followed by extraction, drying of the organic phase and isolation of the pure coupling product by column chromatography.

Drawings

FIG. 1: 1H-NMR spectrum of 9-phenanthrene methyl ether asymmetric dimer in example 1;

FIG. 2: 13C-NMR spectrum of 9-phenanthrene methyl ether asymmetric dimer in example 1;

FIG. 3: 1H-NMR spectrum of 9-phenanthrene ether asymmetric dimer in example 2;

FIG. 4: 13C-NMR spectrum of 9-phenanthrene ether asymmetric dimer in example 2;

FIG. 5: 1H-NMR spectrum of 9-phenanthrenepropyl ether asymmetric dimer in example 3;

FIG. 6: 13C-NMR spectrum of 9-phenanthrenepropyl ether asymmetric dimer in example 3;

Detailed Description

The invention is illustrated by way of example. The specific material ratios, process conditions and results described in the examples are merely illustrative of the invention and the invention should not be, nor should it be limited by the examples.

Example 1

Under nitrogen, 0.2mmol of 9-methoxyphenanthrene (0.0416g) was added to a Schlenk tube, 1mL of dichloromethane was added, and the mixture was stirred to completely dissolve the substrate. Sodium persulfate (5.0equiv.0.238g) was added at 0 ℃ and trifluoroacetic acid (1 mL) was added by injection, maintaining a nitrogen atmosphere. Reacting for 1-3 h under the condition of stirring, wherein the temperature is 25 ℃, and the 9-phenanthrene methyl ether completely disappears through thin-layer chromatography detection. An equal volume of 2mL of water was added to the reaction system along with Na₂CO₃The aqueous solution is neutralized, then the extraction is carried out, the organic phase is dried, and the pure coupling product 9, 10 '-dimethoxy-1, 9' -biphenanthrene (9, 10 '-dimethoxy-1, 9' -biphenyl) is separated by column chromatography, 26.5mg is obtained, the yield is 64 percent, and the purity is more than 95 percent through nuclear magnetic resonance detection.

Example 2

To a Schlenk tube, 0.2mmol of 9-ethoxyphenanthrene (0.0444g) was added under nitrogen, 1mL of toluene was added and the substrate was completely dissolved with stirring. Potassium persulfate (5.0equiv., 0.270g) was added at 0 ℃ and trifluoroacetic acid (1 mL) was added by injection, maintaining a nitrogen atmosphere. Reacting for 1-3 h under the condition of stirring, wherein the temperature is 70 ℃, and the 9-ethoxyphenanthrene completely disappears through thin-layer chromatography detection. An equal volume of 2mL of water was added to the reaction system along with Na₂CO₃The aqueous solution is neutralized, then the extraction is carried out, the organic phase is dried, and the pure coupling product 9, 10 '-diethoxy-1, 9' -biphenanthrene (9, 10 '-diethoxy-1, 9' -biphenyl) is separated by column chromatography, the yield is 56 percent, and the purity is more than 95 percent according to nuclear magnetic resonance detection.

Example 3

To a Schlenk tube, 0.2mmol of 9-propoxyphenanthrene (0.0444g) was added under nitrogen, 1mL of chloroform was added and the substrate was completely dissolved with stirring. Ammonium persulfate (5.0equiv., 0.228g) was added at 0 ℃ and trifluoroacetic acid (1 mL) was added by injection, maintaining a nitrogen atmosphere. Reacting for 1-3 h under the condition of stirring, wherein the temperature is 0 ℃, and the 9-propoxyphenanthrene completely disappears through thin-layer chromatography detection. An equal volume of 2mL of water was added to the reaction system along with Na₂CO₃The aqueous solution is neutralized, then the extraction is carried out, the organic phase is dried, and the pure coupling product 9, 10 '-dipropoxy-1, 9' -biphenanthrene (9, 10 '-dipropyloxy-1, 9' -biphenyl) 24.9mg is separated by column chromatography, the yield is 53 percent, and the purity is more than 95 percent according to nuclear magnetic resonance detection.

Claims

1. A synthetic method of asymmetric 9-alkoxy phenanthrene dimer comprises the following steps:

(1) adding 0.2mmol of 9-alkoxy phenanthrene into a Schlenk tube under the protection of nitrogen, adding a proper amount of organic solvent, and stirring to completely dissolve a substrate;

(2) adding 1.0-10.0 equivalent of persulfate at 0 ℃, adding trifluoroacetic acid by an injection method, and keeping nitrogen atmosphere;

(3) stirring and reacting for 1-3 h at 0-70 ℃, and detecting that the 9-alkoxy phenanthrene completely disappears by thin-layer chromatography;

(4) adding equal volume of water and Na into the reaction system₂CO₃Neutralizing, extracting, drying the organic phase, and separating to obtain pure coupling product by column chromatography;

the coupling product has the following structure:

and R represents methyl or ethyl.

2. The method for synthesizing an asymmetric 9-alkoxyphenanthrene dimer according to claim 1, wherein: the oxidant adopted by the reaction system in the step (2) is K₂S₂O₈、Na₂S₂O₈And (NH)₄)₂S₂O₈One kind of (1).

3. The method for synthesizing an asymmetric 9-alkoxyphenanthrene dimer according to claim 1, wherein: the solvent in the step (1) is dichloromethane or chloroform or a mixed solvent of toluene and trifluoroacetic acid.