Organic material with high photoelectric property and preparation method thereof
1. An organic material with high photoelectric property is characterized in that: the organic material is a gem-dimethyl cyclopentane benzothiophene compound, and the structural general formula of the organic material is as follows:
wherein, C1Is aliphatic five-membered or six-membered ring, geminal dialkyl substituted aliphatic five-membered or six-membered ring or does not exist; ar (Ar)1Is aryl or absent; ar (Ar)2Is aryl or absent。
2. The class of organic materials having high optoelectronic properties as set forth in claim 1 wherein: the gem-dimethyl cyclopentane benzothiophene is a compound which is not limited to the following compounds, in particular to a compound S1, a compound S2-1, a compound S2-2 or a compound S3,
3. the class of organic materials having high optoelectronic properties as set forth in claim 1 wherein: it can be applied to organic electronic devices, organic luminescent materials and battery anode materials.
4. A synthetic method for preparing the organic material with high photoelectric property of claim 1, which has the following reaction formula:
wherein 1 is thiophenyl eneyne, 2 is halogenated thiophene, 3 is thiophenyl aryl eneyne, and S is gem-dimethyl cyclopentanone benzothiophene.
5. The method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: the synthesis method comprises the following steps:
s1, preparing the phenylthioaryl eneyne through a Sonogashira coupling reaction between the thiophenyl eneyne and the halogenated thiophene; wherein the ratio of the halogenated thiophene to the thiophenyl eneyne is 1: 1-5; the equivalent weight of the catalyst is 1-20%; the reaction concentration is 0.05-1M;
s2, utilizing a novel base-mediated Dehydro-Diels-Alder reaction, taking any one of TBD, DBU, pyridine, potassium tert-butoxide and sodium hydroxide as a base, taking any one of o-DCB, DMF, toluene and DMSO as a solvent, taking the thiophenyl aryl eneyne prepared in the step S1 as a reaction substrate, and heating the reaction to 90-210 ℃; wherein the ratio of the reaction substrate to the alkali is 1: 1-20; the reaction concentration is 0.01-0.5M.
6. The method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: step S1 use Pd (OAc) during the coupling reaction2、Pd2(dba)3、Pd(PPh3)4、NiCl2(PCy3)2And any one or a mixture of CuI is used as a catalyst; with Na2CO3、K2PO4、Cs2CO3、NEt3And any one of pyridine is a base; any one of triethylamine, acetonitrile, THF, DMF and ethanol is taken as a solvent; the reaction was heated to 50-120 ℃.
7. The method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: the compound thiophenyl aryl eneyne comprises the following three molecular formulas which are respectively 3a, 3b and 3c, and the chemical formulas of 3a, 3b and 3c are respectively
The synthesis reaction formulas of 3a, 3b and 3c are as follows:
8. the method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: the synthesis reaction formula of compound S1 is as follows:
the method comprises the following specific reaction steps: adding benzene thio thiophene aryl eneyne 3a, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by using a column chromatography method to obtain a compound S1, wherein the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3a to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
9. The method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: the synthesis reaction formulas of the compounds S2-1 and S2-2 are as follows:
the method comprises the following specific reaction steps: adding benzene thiothiophene aryl eneyne 3b, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by using a column chromatography method to obtain a mixture of compounds S2-1 and S2-2, wherein the ratio of the compounds S2-1: S2-2 is 1:2, and the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3b to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
10. The method for synthesizing organic material with high photoelectric property as claimed in claim 4, wherein: the synthesis reaction formula of compound S3 is as follows:
the method comprises the following specific reaction steps: adding benzene thioaryl eneyne 3c, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by using a column chromatography method to obtain a compound S3, wherein the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3c to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
Background
Heterocyclic compounds such as furan, pyrrole and thiophene all have six pi electrons, accord with the Huckel rule, and have aromaticity. Thiophene has a higher electron cloud density than the other two classes of compounds, mainly due to the unique electronic properties of the sulfur atom: compared with other heteroatoms such as nitrogen, oxygen and the like, the composite material has higher resonance energy; the material has high polarizability, so that the material has excellent charge transport performance. The thiophene is embedded into the polycyclic aromatic hydrocarbon, so that the integral pi conjugated structure is not damaged, the integral charge transport capacity is improved due to the electron-rich characteristic, the stability and the oxidation resistance of the polycyclic aromatic hydrocarbon are improved, and the thiophene is an excellent photoelectric material. To date, many scientists have developed different kinds of thiophene-intercalated fused ring compounds and explored their optoelectronic properties. Many semiconductor electronic devices (such as light emitting diodes, organic field effect transistors, etc.) based on benzothiophenes and derivatives thereof have been widely used in real life.
Although thiophene-intercalated fused ring compounds have attracted great attention and are searched in the field of optoelectronics, the currently developed thiophene-intercalated fused ring compounds are relatively limited in variety, and most of the synthetic methods are limited to metal-mediated cyclization reactions, and have the disadvantages of high toxicity, high cost, strong corrosiveness, difficulty in recovery and the like; non-metal mediated reactions are reported less and lack systematic summary studies. Moreover, these reactions have some common disadvantages, most of which are capable of forming only one aromatic skeleton under each reaction condition. Therefore, the development of novel thiophene-embedded condensed ring compounds and a novel synthesis method have great significance in the field of organic photoelectric materials.
Disclosure of Invention
In order to solve the defects of the prior art, the invention aims to provide a benzothiophene compound substituted by gem-dimethyl cyclopentane with excellent performance, so that the problem of lack of organic small-molecule photoelectric materials is solved, and a simple and effective synthesis method is provided for synthesis of substituted benzothiophene based on the novel material.
Specifically, the invention provides an organic material with high photoelectric property, wherein the organic material is a gem-dimethyl cyclopentane benzothiophene compound, and the structural general formula of the organic material is as follows:
wherein, C1Is aliphatic five-membered or six-membered ring, geminal dialkyl substituted aliphatic five-membered or six-membered ring or does not exist; ar (Ar)1Is aryl or absent; ar (Ar)2Is aryl or absent.
Preferably, the described gem-dimethyl cyclopentanobenzothiophene may be, but is not limited to, compounds including, in particular, compound S1, compound S2-1, compound S2-2 and compound S3,
preferably, the invention also provides a synthetic method of the gem-dimethyl cyclopentane benzothiophene compound, which has the following reaction formula:
wherein 1 is thiophenyl eneyne, 2 is halogenated thiophene, 3 is thiophenyl aryl eneyne, and S is gem-dimethyl cyclopentan-benzothiophene.
Preferably, the synthesis method comprises the following steps:
s1, preparing the phenylthioaryl eneyne through a Sonogashira coupling reaction between the thiophenyl eneyne and the halogenated thiophene; wherein the ratio of the halogenated thiophene to the thiophenyl eneyne is 1: 1-5; the equivalent weight of the catalyst is 1-20%; the reaction concentration is 0.05-1M;
s2, utilizing a novel base-mediated Dehydro-Diels-Alder (DDA) reaction, taking any one of TBD, DBU, pyridine, potassium tert-butoxide and sodium hydroxide as a base, taking any one of o-DCB, DMF, toluene and DMSO as a solvent, taking the thiophenyl aryl eneyne prepared in the step S1 as a reaction substrate, and heating the reaction to 90-210 ℃; wherein the ratio of the reaction substrate to the alkali is 1: 1-20; the reaction concentration is 0.01-0.5M.
Preferably, step S1 is carried out in the course of the coupling reaction in Pd (OAc)2、Pd2(dba)3、Pd(PPh3)4、NiCl2(PCy3)2And any one or a mixture of CuI is used as a catalyst; with Na2CO3、K2PO4、Cs2CO3、NEt3And any one of pyridine is a base; any one of triethylamine, acetonitrile, THF, DMF and ethanol is taken as a solvent; the reaction was heated to 50-120 ℃.
Preferably, in step S1, the thiophenoalkenylene is synthesized as follows:
under the action of alkali, cyclohexanedione and trifluoromethanesulfonic anhydride generate keto trifluoromethanesulfonate, and then the keto trifluoromethanesulfonate is reduced to hydroxyl trifluoromethanesulfonate;
reacting chloromethyl phenylsulfide with triethyl phosphite to generate phenylthio diethyl phosphate;
the hydroxy triflate is olefinated in series with diethyl thiophenylphosphate to form a benzothienylene alkyne.
Preferably, the compound benzenethiaaryleneyne comprises the following three formulas, 3a, 3b and 3c, respectively, and the chemical formulas of 3a, 3b and 3c are respectively
The compound thiophenyl aryl eneyne comprises the following three molecular formulas which are respectively 3a, 3b and 3c, and the chemical formulas of 3a, 3b and 3c are respectively
The synthesis reaction formulas of 3a, 3b and 3c are as follows:
preferably, the synthesis reaction formula of compound S1 is as follows:
the method comprises the following specific reaction steps: adding benzene thio thiophene aryl eneyne 3a, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by using a column chromatography method to obtain a compound S1, wherein the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3a to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
Preferably, the synthesis reaction formulas of the compounds S2-1 and S2-2 are as follows:
the method comprises the following specific reaction steps: adding benzene thiothiophene aryl eneyne 3b, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, purifying by using a column chromatography method to obtain a mixture of compounds S2-1 and S2-2, wherein the ratio of the compounds S2-1: S2-2 is 1:2, and the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3b to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
Preferably, the synthesis reaction formula of compound S3 is as follows:
the method comprises the following specific reaction steps: adding benzene thioaryl eneyne 3c, TBD and o-DCB into a dry pressure-resistant pipe, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by using a column chromatography method to obtain a compound S3, wherein the reaction is heated to 90-210 ℃; the ratio of the thiophenyl aryleneyne 3c to the alkali TBD is 1: 1-20; the reaction concentration is 0.01-0.5M.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention provides a benzothiophene compound substituted by gem-dimethyl cyclopentane with excellent performance, thereby solving the problem of lack of organic micromolecule photoelectric materials, and providing a simple and effective synthesis method for the synthesis of substituted benzothiophene based on the novel material.
(2) The invention applies the DDA reaction mediated by alkali (TBD) to the synthesis of substituted benzothiophene for the first time; the synthesis of the novel gem-dimethyl cyclopentane-substituted benzothiophene with different frameworks is realized under the same reaction condition, the reaction yield is excellent, and the condition is mild.
(3) The synthesized novel benzothiophene shows excellent photoelectric properties in relevant tests. In the voltammetry cyclic curve test, all compounds show obvious oxidation wave potential, which indicates that the compounds have stronger electron donating capability. In particular, the compound S2 shows the longest absorption emission wavelength and the lowest oxidation wave potential, and is an excellent novel electrode and organic photoelectric device material. The organic light-emitting diode can be applied to the fields of organic electronic devices, organic light-emitting materials, battery anode materials and the like.
Drawings
FIG. 1 is a scheme showing the synthesis of gem-dimethyl cyclopentanobenzothiophene;
FIG. 2 is a 1H NMR spectrum of S1 which is a product obtained in example 5;
FIG. 3 is a 13C NMR spectrum of S1 which is a product obtained in example 5;
FIGS. 4 a-4 c are UV-vis absorption spectra of compounds S1, S2, and S3;
FIGS. 5 a-5 c are fluorescence emission spectra of compounds S1, S2, and S3 in solution and thin film;
FIGS. 6 a-6 c are voltammetric cycling curves for compounds S1, S2, and S3.
Detailed Description
Exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
Specifically, the invention provides an organic material with high photoelectric property, wherein the organic material is a gem-dimethyl cyclopentane benzothiophene compound, and the structural general formula of the organic material is as follows:
wherein, C1Is aliphatic five-membered or six-membered ring, geminal dialkyl substituted aliphatic five-membered or six-membered ring or does not exist; ar (Ar)1Is aryl or absent; ar (Ar)2Is aryl or absent.
Preferably, the described gem-dimethyl cyclopentanobenzothiophene may be specified as, but not limited to, the following compounds:
preferably, the invention also provides a synthetic method of the gem-dimethyl cyclopentane benzothiophene compound, which has the following reaction formula:
wherein 1 is thiophenyl eneyne, 2 is halogenated thiophene, 3 is thiophenyl aryl eneyne, and S is gem-dimethyl cyclopentan-benzothiophene.
Preferably, the synthesis method comprises the following steps:
s1, preparing the phenylthioaryl eneyne through a Sonogashira coupling reaction between the thiophenyl eneyne and the halogenated thiophene; wherein the ratio of the halogenated thiophene to the thiophenyl eneyne is 1: 1-5; the equivalent weight of the catalyst is 1-20%; the reaction concentration is 0.05-1M;
s2, Dehydro-Diels-Alder reaction mediated by a novel base. Taking any one of TBD, DBU, pyridine, potassium tert-butoxide and sodium hydroxide as a base, taking any one of o-DCB, DMF, toluene and DMSO as a solvent, taking the thiophenyl aryl eneyne prepared in the step S1 as a reaction substrate, and heating the reaction to 90-210 ℃; wherein the ratio of the reaction substrate to the alkali is 1: 1-20; the reaction concentration is 0.01-0.5M.
Step S1 use Pd (OAc) during the coupling reaction2、Pd2(dba)3、Pd(PPh3)4、NiCl2(PCy3)2And any one or a mixture of CuI is used as a catalyst; with Na2CO3、K2PO4、Cs2CO3、NEt3And any one of pyridine is a base; any one of triethylamine, acetonitrile, THF, DMF and ethanol is taken as a solvent; the reaction was heated to 50-120 ℃.
Example 1:
the synthesis of the thiophenoalkylene (1) comprises the following steps:
synthesis of a-ketotriflate (c):
to a suspension of cyclohexanedione (a,1.38g) in dichloromethane (50mL) was added base (1.59 mL). The mixture was stirred at-78 ℃ for 10 minutes and trifluoromethanesulfonic anhydride (b,1.98mL) was added dropwise. Stirring at-71 deg.C for 20 min, heating to 0 deg.C, stirring for 20 min, and stirring at room temperature for 30 min. After the starting cyclohexanedione (a) had been completely consumed, the reaction was quenched and extracted 3 times with anhydrous ether. Na for organic layer2CO3Washing with aqueous solution and water, and adding anhydrous Na2SO4Drying and concentrating by rotary evaporation to obtain a crude product. Purification by column chromatography gave 2.54g of ketotriflate (c) which was obtainedThe ratio was 95%.
b Synthesis of hydroxy triflate (d):
to a mixture of ketotriflate (c,2.67g) in tetrahydrofuran (40mL) at-71 deg.C was added slowly 11.77mL of reducing agent (1.0M solution in toluene). The reaction mixture was stirred at-78 ℃ for 10 minutes, warmed to 0 ℃ and stirred for 10 minutes, and stirred at room temperature for 30 minutes. Diluting the reaction with anhydrous ether, cooling to 0 ℃, and adding NaOH aqueous solution to quench the reaction. The mixture was stirred for 15 minutes until a gel formed, and then anhydrous MgSO was added4Drying to remove water. Adding anhydrous MgSO4After that, the mixture was stirred for another 15 minutes. Concentration by vacuum filtration and rotary evaporation gave the crude product. Column chromatography separation with different gradient eluents gave 2.61g of the hydroxy triflate (d) in 97% yield.
c Synthesis of diethyl phenylthiophosphate (g):
a round bottom flask was charged with chloromethyl phenylsulfide (e,0.63g) and triethyl phosphite (f,1.67 g). The resulting mixture was heated to reflux. Purification by column chromatography gave 0.967g of diethyl phenylthiophosphate (g) in 93% yield.
Synthesis of d-thiophenoalkenylene (1):
4.15mL of organolithium reagent (1.6M solution in hexanes) was slowly added to 70mL of diisopropylamine in tetrahydrofuran (0.1M) at-78 ℃. The mixture was stirred at-78 ℃ for 10 minutes, warmed to 0 ℃ and stirred for 30 minutes, then cooled to-78 ℃ and hydroxy triflate (d,0.784g) and diethyl thiophenylphosphate (g,0.82g) were added. Will getThe resulting mixture was stirred at-78 ℃ for 10 minutes, warmed to 0 ℃ for 10 minutes, stirred at room temperature for 30 minutes, and heated to reflux in a 60 ℃ oil bath for 2 hours. After 2 hours, the reaction mixture was cooled to room temperature and the reaction was quenched. Extracted 3 times with anhydrous ether. The organic layer was washed with water and anhydrous Na2SO4Drying and purification by column chromatography gave 0.547g of thiophenylenylene (1) in 83% yield.
Example 2:
synthesis procedure for Compound (3 a):
in a dry flask, 2-iodothiophene (2a,57.6mg), Pd (PPh)3)2Cl2(11.4mg) and CuI (3.1 mg). Under the protection of nitrogen, NEt is added3(0.1M), after stirring for 5 minutes, thiophenoalkylene (1,71mg) was added dropwise, and the reaction mixture was heated to reflux. TLC observed that the substrate 2-iodothiophene (2a) was absent and cooled to room temperature. The reaction mixture was passed through a flash column of silica gel and celite and concentrated by rotary evaporation to give the crude product. Then, purification by column chromatography was carried out to obtain a yellow oily liquid (3a) in a yield of 96%.
Example 3:
synthesis procedure for Compound (3 b):
in a dry flask, aryl bromide (2b,100mg), PdCl were added2(CH3CN)2(4.9mg), XPhos (27.2mg) and Cs2CO3(248.4 mg). Under nitrogen, anhydrous acetonitrile was added, stirred for 25 minutes, benzenethioeneyne (1,98.9mg) was added dropwise, and the reaction mixture was heated to reflux. Stopping reaction, cooling to room temperature, extracting with anhydrous ether for three times, washing organic phase with deionized water to neutrality, washing with saturated salt solution, drying with anhydrous sodium sulfate, rotary evaporating for concentrating to obtain crude product, and performing column chromatographyPurification gave a yellow oily liquid (3b) in 88% yield.
Example 4:
synthesis procedure for Compound (3 c):
in a dry flask, aryl bromide (2c,78mg), PdCl were added2(CH3CN)2(8.3mg), XPhos (45.8mg) and Cs2CO3(209 mg). Under nitrogen, anhydrous acetonitrile was added, stirred for 25 minutes, a benzothienylene alkyne (1,200mg) was added dropwise, and the reaction mixture was heated to reflux. After 28 hours, the reaction was completely stopped. Work-up procedure synthesis of reference compound (3 b). Then, purification by column chromatography was carried out to obtain a yellow oily liquid (3c) in 89% yield.
Example 5:
synthetic procedure for compound (S1):
the desired gem-dimethyl cyclopentanobenzothiophene (S1) was obtained in 88% yield by adding a benzothiophene aryleneyne (3a,90mg), TBD (80mg,) and o-DCB to a dry pressure tube, heating the mixture to reflux, after cyclization was complete, cooling to room temperature and purification by column chromatography. Characterization data: 1H NMR (400MHz, CDCl)3):δ7.61(s,1H),7.29(d,J=5.44Hz,1H),7.21(d,J=5.44Hz,1H),2.80-2.77(m,4H),1.15(s,6H);13C NMR(400MHz,CDCl3) Delta 141.01,140.70,138.27,137.85,124.63,123.19,118.99,117.86,47.20,47.03,40.70 and 28.37 (see figures 2 and 3 for specific spectrogram).
Example 6:
synthetic procedure for compound (S2):
adding benzothiophene aryleneyne (3b,68mg), TBD (44.5mg) and o-DCB into a dry pressure-resistant tube, heating the mixture to reflux, cooling to room temperature after cyclization is completed, and purifying by column chromatography to obtain the desired gem-dimethylcyclopentanobenzothiophene (S2 mixture: S2-1: S2-2: 1:2) with a total yield of 79%.
Example 7:
synthetic procedure for compound (S3):
the desired gem-dimethyl cyclopentanobenzothiophene (S3) was obtained in 57% yield by adding a benzenethioaryl eneyne (3c,150mg), TBD (154.4mg) and o-DCB to a dry pressure tube, heating the mixture to reflux, after cyclization was complete, cooling to room temperature and purification by column chromatography.
Example 8:
the prepared gem-dimethyl cyclopentane benzothiophene (S1, S2 and S3) is dissolved in tetrahydrofuran to prepare a 0.01mM solution, and then a UV-vis absorption spectrum test is carried out to further study the photophysical properties of the gem-dimethyl cyclopentane benzothiophene. As a result, as shown in FIG. 4, the maximum absorptions of the compounds (S1, S2, and S3) occurred at 232nm, 265nm, and 241nm, respectively.
Example 9:
after obtaining the UV-vis absorption spectra, the photoluminescence behavior of gem-dimethylcyclopentanobenzothiophene in solution and solid state (thin film) was investigated. As shown in FIG. 5, in the solution (0.01mM in THF), the maximum emission of the compounds (S1, S2, and S3) occurred at 318nm, 359nm, and 339nm, respectively. Their fluorescence emission spectra in the solid state are very different from those in the solution, and besides the large change in the peak pattern, the emission values are also greatly different, and the maximum emission thereof also appears at 346nm, 390nm and 358nm in this order. Their maximum emission wavelengths were red-shifted by 28nm, 31nm and 19nm, respectively, compared to the solution, with compound (S2) being the most red-shifted.
Example 10:
the electrochemical properties of gem-dimethyl cyclopentanobenzothiophene (S1, S2, and S3) were investigated by voltammetric cycling. Voltammetric cyclic Curve (CV) testing was performed on an electrochemical analyzer in solution in a three-electrode cell with Bu4NFPF6Is dissolved in CH2Cl2Medium (0.1M) as electrolyte, sample concentration 1X 10-3And M. The working electrode was a platinum electrode (0.6 cm)2) The counter electrode is a platinum sheet (0.5 cm)2) The reference electrode was an Ag/AgCl electrode, the scan rate was 50mV/s, and the test was performed at room temperature. The results are shown in FIG. 6, compared to Fc/Fc+In other words, compound (S1) exhibited a distinct oxidation wave potential at 1.26V; compound (S2) exhibited reversible oxidation wave potentials at 0.96V and 1.19V, respectively; the compound (S3) showed an oxidation wave potential only at 1.30V. These data indicate that the compounds (S1, S2, and S3) all exhibit relatively strong electron donating ability and excellent electrochemical properties.
Finally, it should be noted that: the above-mentioned embodiments are only used for illustrating the technical solution of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.