ES2815249B2 - POLYHETEROAROMATIC COMPOUNDS AND THEIR USE FOR CHARGE TRANSPORTATION IN ELECTRONIC DEVICES - Google Patents

Description

DESCRIPTION

POLYHETEROAROMATIC COMPOUNDS AND THEIR USE FOR CHARGE TRANSPORTATION IN ELECTRONIC DEVICES

field of invention

The present invention falls within the general field of organic chemistry, and in the field of organic electronics in particular, and specifically, refers to compounds of a polyheteroaromatic nature and their use in the manufacture of electronic devices such as transistors, light-emitting devices, solar cells, capacitors, supercapacitors, photodetectors, lasers or sensors, among others.

Background of the invention

Optoelectronic devices are made up of a combination of various materials, generally arranged as a sequence of thin films, each film performing a function that allows the correct operation of the device.

The operation of any electronic device involves the circulation of an electric current, that is, a transport of electric charge through the different materials that make up the device.

For the correct transport of charge inside a device, the use of materials that selectively transport a type of carrier (electron or hole) is used.

Some organic materials have semiconducting properties propitiated by their structure. Regarding the molecular structure of organic semiconductors, these are characterized by the existence of conjugation in part, or all of their structure.

However, the transport of electrical charge through materials of an organic nature is greatly hindered by the disorder inherent in organic molecules.

The modification in the molecular structure of an organic material affects its packaging mode and/or the morphology of the film in which it is integrated within the electronic device. In turn, the mode of packing and/or film morphology influence the quality of charge transport.

A charge-carrying material must have an electronic structure that is well aligned with that of adjacent materials to promote migration of the desired charge carrier.

The charge-carrying materials must have a charge mobility in accordance with the necessary requirements for the application of the optoelectronic device.

In the case of devices involving the absorption or emission of light, the charge-carrying materials should preferably be transparent to the radiation that needs to be absorbed or emitted so as not to interfere with the correct operation of the device.

In addition, the stability of organic materials is another aspect to consider, since it conditions the degradation of electronic devices and their useful life.

In response to all the reasons indicated, research on conjugated compounds that allow optimal operation of optoelectronic devices in their organic version represents a challenge for the current state of the area of organic electronics (Adv. Mater. 2018, 30, 1800455 Adv Energy Mater 2018, 8, 1702730 J Mater Chem C 2018 6 8280 J Mater Chem C 2017 5 8654 J Amer Chem Soc 2013 135 6724; Adv Mater.

2013, 25, 6158; Chem Rev 2011, 112, 2208). However, the ideal materials are not yet available to promote the development of this technology towards the industrial phase, and research that leads to the discovery of new materials is required.

There is therefore a need to provide compounds that solve the problems described above in such a way that they allow a better operation of the optoelectronic devices in which they are found.

Description of the invention

The present invention solves the problems cited in the state of the art since it provides compounds that allow control over the orientation of some molecules with respect to others, thus favoring ordering in the solid state, in addition, the compounds of the present invention can be used in the transport of holes in optoelectronic devices, improving their performance, and in charge-carrying layers in electronic devices.

Thus, in a first aspect, the present invention relates to a polyheteroaromatic compound of general formula (I) (hereinafter compound of the present invention) and its isomeric forms.

General formula (I)

where

Ari is selected from an aromatic, polyaromatic, heteroaromatic, polyheteroaromatic structure or a combination thereof, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings,

n is an integer between 1-2,

R1, R2, R3, R4, R5, R6 are the same or different selected from hydrogen, fluorine, chlorine, bromine, iodine atoms, linear or branched (C3-C20) alkyl groups, linear or branched (C3-C20) alkoxy groups. branched, aromatic, polyaromatic, heteroaromatic or polyheteroaromatic structure, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings,

where R1 and R2 and/or R2 and R3 and/or R4 and R5 and/or R5 and R6 may or may not be directly linked to each other, giving rise to a substituted or unsubstituted aromatic or heteroaromatic ring and may or may not be fused to other rings,

where the compound with general formula (I) is excluded where R1= R2 = R3 = R4 =R5 = R6 =H, n=1 and Ar1 is benzene and its isomeric forms and

where the compound 1,9-dihydropyrene[2,1-b:7,6-b']di(7-azaindole) is excluded.

In the present invention, aromatic structure refers to a planar, cyclic substituent or molecule with conjugated bonds that obeys Hückle's rule.

In the present invention, polyaromatic structure refers to a substituent or molecule made up of several fused or linked aromatic units.

In the present invention, heteroaromatic structure refers to a substituent or molecule that meets the premises described for the aromatic structure, but has heteroatoms integrated in the cycle.

In the present invention, polyheteroaromatic structure refers to a substituent or molecule made up of several fused or linked heteroaromatic units.

In the present invention, by fused rings it is meant that two rings share a bond that is part of the respective cycles simultaneously. Fused structures are not restricted to two rings, but can result from the fusion of several rings through different bonds.

In the present invention by linked rings it is meant that two or more rings are joined through sigma bonds.

In the present invention, alkyl group refers to a hydrocarbon structure without any type of unsaturation.

In the present invention, alkoxy or alkoxy group refers to an oxygen atom bonded to an alkyl group.

In the present invention, by linear chains it refers to structures of the alkyl or alkoxy type that do not include any substituents.

In the present invention, branched chains refer to structures of the alkyl or alkoxy type which in turn contain other substituents.

In the present invention, by isomeric forms, they refer to structural isomerism, in particular, in the present invention by structural isomeric forms, it refers to those compounds that have the same molecular formula, but have a different distribution of bonds between their atoms.

In a particular embodiment, the compound of general formula (I) is the isomeric form according to general formula (II).

where the isomers corresponding to the compound with general formula (I) are excluded where R1= R2 = R3 = R4 =R5 = R6 =H, n=1 and Ar1 is benzene and its isomeric forms.

In a particular embodiment, the present invention refers to the compound with the general formula (I) of the present invention where Ar1 is naphthalene, Ri=R2=R3=R4=R5=R6=H and n=1.

In a particular embodiment, the present invention refers to the compound of general formula (I) of the present invention where Ar1 is anthracene, R1= R2 = R3 = R4 = R5 = R6 =H and n=1.

In a particular embodiment, the present invention refers to the compound of general formula (II) of the present invention where Ar1 is pyrene, R1= R2 = R3 = R4 = R5 = R6 =H and n=1.

In a particular embodiment, the present invention refers to the compound of general formula (I) of the present invention where Ar1 is benzene, R1= R2 = R3 = R4 = R5 = R6 =H and n=2.

In another aspect, the present invention relates to a process for the preparation of the compounds of the present invention, starting from the intermediate compound of general formula (NO

where:

Ar1 is selected from an aromatic, polyaromatic, heteroaromatic, polyheteroaromatic structure or a combination thereof, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings.

n is an integer between 1-2,

X is a halogen atom selected from chlorine, bromine or iodine.

R1, R2, R3, R4, R5, R6 are the same or different selected from hydrogen, fluorine, chlorine, bromine, iodine atoms, linear or branched (C3-C20) alkyl groups, linear or branched (C3-C20) alkoxy groups. branched, aromatic, polyaromatic, heteroaromatic or polyheteroaromatic structure, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings,

where R1 and R2 and/or R2 and R3 and/or R4 and R5 and/or R5 and R6 may or may not be directly linked to each other, giving rise to a substituted or unsubstituted aromatic or heteroaromatic ring and may or may not be fused to other rings.

In another aspect, the present invention relates to the use of the compound of the present invention in the preparation of hole transporting layers in optoelectronic devices.

In another aspect, the present invention relates to the use of the compound of the present invention in the preparation of charge transporting layers in electronic devices.

In another aspect, the present invention relates to an electronic device and/or optoelectronic compound comprising the compound of the present invention.

Description of the figures

Figure 1 shows the schematic of a transistor architecture in which the following layers are included:

1: gate electrode

2: dielectric

3: dielectric coating

4: semiconductor constituted by the compound of the present invention.

5: contact layer

6: source electrode

7: collector electrode

Figure 2 shows the architecture scheme of an inverted architecture solar cell, with the following layers:

11: transparent substrate

12: transparent electrode (anode)

13: anode contact layer

14: hole transporting layer with the compound of the present invention

15: active layer

16: electron transport layer

17: cathode contact layer

18: metal electrode (cathode)

Figure 3 shows the architecture scheme of a conventional architecture solar cell, with the following layers:

11: transparent substrate

22: transparent electrode (cathode)

23: cathode contact layer

24: electron transport layer

15: active layer

26: hole transporting layer with the compound of the present invention

27: anode contact layer

28: metal electrode (anode)

Detailed description of the invention

Example 1: Synthesis of N,N'-bis ( 3-chloropyridin-2-yl)anthracene-1,5-diamine

In a round-bottom flask, a mixture containing (±)BINAP (0.19 g, 7.5 mol%) Pd(OAc)2 (0.046 g, 5 mol%) and 1,4-dioxane (35 mL) was prepared, and heated at 80°C for 15 minutes. In another round bottom flask a mixture containing 1,5-diaminoanthracene (0.85 g, 4.09 mmol), 2,3-dichloropyridine (1.39 g, 9.40 mmol), potassium tert-butoxide (1.37 g, 12.3 mmol) was prepared. and dioxane (40 mL). The contents of the first mixture were added to the flask containing the second mixture and the resulting mixture was heated at reflux temperature for 24 hours. Subsequently, the mixture was allowed to cool to room temperature and the solvent was evaporated. The solid obtained was washed with water and with methanol to obtain the expected product N,N'-bis ( 3-chloropyridin-2-yl)anthracene-1,5-diamine with a yield of 68%.

Example 2: Synthesis of antra[1,2-b:5,6-b]di-7-azaindole.

In a photochemical reactor, a mixture of the compound obtained in example 1 (0.90 g, 2.09 mmol), potassium tert-butoxide (0.93 g, 8.35 mmol) and dimethylsulfoxide (160 ml) was prepared, which was irradiated with a mercury lamp. medium pressure for 2.5 hours. After the mixture was allowed to cool to room temperature, it was poured onto a saturated ammonium chloride solution which was at 0°C. The precipitate obtained was filtered and washed with water and methanol to obtain the product antra[1,2-b:5,6-b]di-7-azaindole with 96% yield.

Example 3: use of the compound of example 2 for the manufacture and characterization of solar cells.

inverted architecture.

A substrate consisting of glass covered by an ITO film in the shape of a pattern predefined, it was rinsed in an ultrasonic bath, sequentially, with acetone, water and isopropanol (5 minutes each step) and subsequently subjected to a UV-ozone treatment for 30 minutes. The substrates were introduced in a sublimation equipment integrated in a box with an inert atmosphere to deposit a film of the compound obtained in Example 2, which acted as a transport layer for holes. Subsequently, another film was deposited on this film, using the spin-coating technique, which acted as an active layer and corresponded to a perovskite-type compound formed in a solution of PbCh (0.2 M), Pb(CH3COO)2 (0.8 M) , and CH3NH3I (3M) in dimethylformamide. The substrate was then baked at a temperature of 100°C for 10 minutes. Subsequently, using the spin-coating technique, a PCBM film ([6 ,6 ]-phenyl-C61-methyl butyrate) was deposited in chloroform and chlorobenzene solution, which acted as an electron transport layer. The substrate was put back into the sublimation equipment to deposit a lithium fluoride film and an aluminum electrode. The manufactured solar cell was characterized by irradiating it with a lamp that simulates sunlight and measuring the variation in current intensity resulting from applying a potential sweep (-0.2V to 1.1V).

conventional architecture.

A tin oxide film from an aqueous solution (15%) was deposited on an ITO substrate by spin-coating. Next, using the same technique, a PCBM film was deposited, which served as the electron transport layer, from a solution in chlorobenzene. Next, the active layer consisting of a perovskite-type compound was deposited using spin-coating. Subsequently, the film that acted as a hole transporting layer was added. To do this, sublimation of the compound obtained in example 2 is used. The device was completed by sequential sublimation of a molybdenum trioxide film and a gold electrode. The solar cell was characterized in the same way as described in the immediately preceding case.

Example 4: use of the compound of example 2 for the manufacture and characterization of transistors.

A doped silicon substrate coated with a layer of silicon oxide was sequentially rinsed with water, acetone and isopropanol (5 min each step). Next, a layer of polystyrene was deposited from a solution in toluene, using the spin-coating technique. Subsequently, the substrates were transferred to an evaporation unit integrated in an inert atmosphere box and a layer of the compound obtained in example 2 was deposited. Next, a layer of molybdenum trioxide was sublimated, followed by the gold source and collector electrodes. , using a mask to define the transistor channel with a length of 40-140 ^m. The device was characterized by measuring current intensity variations in response to a potential sweep (0V to -80V).

Molecular design with the compounds of the present invention allowed control over the orientation of some molecules with respect to others, favoring their arrangement in the solid state.

The properties of the compounds of the present invention were suitable to intervene in the transport of holes in optoelectronic devices and improve their performance.

The compounds of the present invention could be deposited, in the form of a thin film, by both liquid phase processing techniques and vapor phase processing techniques.

The application of this type of film is suitable for integration as charge-carrying layers in the architecture of various types of electronic devices (transistors, light-emitting devices, solar cells, capacitors, supercapacitors, photodetectors, lasers or sensors) and can improve their benefits.

Claims (9)

1. Polyheteroaromatic compound of general formula (I) and its isomeric forms

General formula (I) where An is selected from an aromatic, polyaromatic, heteroaromatic, polyheteroaromatic structure or a combination thereof, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings, n is an integer between 1 - 2 R1, R2, R3, R4, R5, R6 are the same or different selected from hydrogen, fluorine, chlorine, bromine, iodine atoms, linear or branched (C3-C20) alkyl groups, linear or branched (C3-C20) alkoxy groups. branched, aromatic, polyaromatic, heteroaromatic or polyheteroaromatic structure, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings, where R1 and R2 and/or R2 and R3 and/or R4 and R5 and/or R5 and R6 may or may not be directly linked to each other, giving rise to a substituted or unsubstituted aromatic or heteroaromatic ring and may or may not be fused to other rings, where in addition, the compound with general formula (I) is excluded where R1= R2 = R3 = R4 =R5 = R6 =H, n=1 and Ar1 is benzene and its isomeric forms, and 1,9-dihydropyrene[2 ,1-b:7,6-b']di(7-azaindole).2 2. Polyheteroaromatic compound according to claim 1, where Ar1 is naphthalene, R1= R2 = R3 = R4 = R5 = R6 =H and n=1. 3. Polyheteroaromatic compound according to claim 1, where Ar1 is anthracene, Ri= R2 = R3 = R4 = R5 = R6 =H and n=1. 4. Polyheteroaromatic compound according to claim 1, where Ar1 is pyrene, R1= R2 = R3 = R4 = R5 = R6 =H and n=1. 5. Polyheteroaromatic compound according to claim 1, where Ar1 is benzene, R1=R2=R3=R4=R5=R6=H and n=2. 6. Process for the preparation of a polyheteroaromatic compound of general formula (I), according to any of claims 1-5, starting from the intermediate compound of general formula (III)

General formula (III) Ar1 is selected from an aromatic, polyaromatic, heteroaromatic, polyheteroaromatic structure or a combination thereof, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings. n is an integer between 1-2, X is a halogen atom selected from chlorine, bromine or iodine. R1, R2, R3, R4, R5, R6 are the same or different selected from hydrogen, fluorine, chlorine, bromine, iodine atoms, linear or branched (C3-C20) alkyl groups, linear or branched (C3-C20) alkoxy groups. branched, aromatic, polyaromatic, heteroaromatic or polyheteroaromatic structure, where said structure has rings of 5-60 atoms and where said rings are selected from individual, fused and linked rings, where R1 and R2 and/or R2 and R3 and/or R4 and R5 and/or R5 and R6 may or may not be directly linked to each other, giving rise to a substituted or unsubstituted aromatic or heteroaromatic ring and may or may not be fused to other rings. 7. Use of the compound of general formula (I) according to any of claims 1-5 in the preparation of hole-transporting layers in optoelectronic devices. 8. Use of the compound of general formula (I) according to any of claims 1-5, for the preparation of charge-transporting layers in electronic devices. 9. Electronic and/or optoelectronic device comprising a compound of general formula (I) according to any of claims 1-5.