Mechanochemical method for deuterating organic compounds

Abstract

The present invention relates to a process for deuteration of organic compounds by means of a mechanochemical treatment.

Description

[0001] MECHANOCHEMICAL METHOD FOR DEUTERATING ORGANIC COMPOUNDS

[0002] The present invention relates to a method for deuterating an organic compound, and to deuterated compounds obtained by said method.

[0003] Deuterium (2H) is one of the two stable isotopes of hydrogen (besides protium,1H) and has a natural abundance of approximately 0.0156% (0.0312% by mass) of all the naturally occurring hydrogen in the oceans.

[0004] Deuterated compounds, in which the level of deuterium is intentionally enriched, are known. For example, deuterated aromatic compounds have often been used in studies of the course of chemical reactions or conversions in metabolism. Deuterated aromatic compounds are also used as starting materials for pharmaceutical compounds or markers.

[0005] Also well-known is the use of deuterated organic or metallorganic compounds in electronic devices. More particularly, the use of deuterated organic or metallorganic compounds in organic electroluminescent devices (OLEDs) can drastically improve the OLEDs performances in terms of efficiency and lifetime as disclosed, for example, in WO 2010 / 099534, WO 2011 / 050888 or J. Phys. Chem. C 2007, 111 , 3490-3494.

[0006] Within the context of this invention, electronic devices are understood to mean organic electronic devices, which contain organic semiconductor materials as functional materials. In particular, the electronic devices stand for organic electroluminescent (EL) devices such as organic light emitting diodes (OLEDs).

[0007] The general structure and operation mode of organic electroluminescent (EL) devices is known to those skilled in the art from the prior art, for example, from US 4539507, US 5151629, EP 0676461 and WO 98 / 27136. In general, organic electroluminescent (EL) devices are understood to mean electronic devices containing spaced electrodes which are separated by one or more layers that comprise organic compounds, which form the so-called organic light emitting structure, and emit light when a voltage is applied. Within the present application, any layer of an organic electronic device which comprises one or more organic compounds as functional materials will also be called “organic layer”.

[0008] In general, a higher deuteration degree than in nature can be achieved by reacting building blocks together, where at least one of the building blocks has been enriched with deuterium beforehand via a deuteration method (as described in WO 2011 / 050888), or by deuterating a compound via a deuteration method once it has been synthesized (as described in WO 2010 / 099534).

[0009] However, deuteration methods for the synthesis of deuterated compounds can be quite challenging, time-consuming and also costly. In general, the practical realization of deuterating an organic compound essentially relies on two approaches that represent the state of the art: On the one hand, acid- catalyzed processes using a deuterated aromatic solvent (e.g. benzene-d6or toluene-d8) as deuterium source, as described, for example, in WO 2011 / 053334. Such processes, however, suffer from the intrinsic drawback of high costs for the deuterium source, since deuterium is commercially enriched as D2O, and all other deuterated solvents are obtained upstream. One the other hand, metal-catalyzed processes that use D2O as a deuterium source combined with a metal catalyst and an organic solvent as described, for example, in WO 2016 / 073425 or KR 20180130970 A. For such processes, however, only certain solvents that are innocent to competitive deuteration are feasible in use. In addition, the solubility of OLED-materials is generally rather low, such that the reactions oftentimes do not give a viable conversion and the highly diluted conditions lead to low time / volume yields, thereby diminishing the process efficiency.

[0010] By employing high temperatures to boost the solubility, as suggested in some deuteration methods, unwanted side reactions, including but not limited to a transfer of hydrogenation from the solvent, may arise. Generally, harsh conditions typically applied to promote chemical H-D exchange in order to obtain high deuteration degrees lead to the disadvantage that impurities can be formed at the same time. On the other side, when performed under mild conditions, only a low deuteration degree can be achieved with said processes.

[0011] Therefore, there is always a need for deuteration methods that can overcome at least some of the above-outlined drawbacks for forming various deuterated compounds that can be used in OLEDs, but also for forming deuterated building blocks that can be used in the synthesis of deuterated compounds. In particular, there is a need for deuteration methods that can be performed under mild conditions and still result in high deuteration degree and process efficiency.

[0012] It is therefore an object of the present invention to provide a method for preparing deuterated compounds that overcomes at least some of the aboveoutlined drawbacks and allows for one or more of the following advantages: low reaction temperatures alongside with a decrease in the extent of side reactions, high conversation and H-D exchange rates, fast reaction times, and high environmental compatibility due to reduced amounts of solvents and improved recyclability of process components.

[0013] Thus far, the aforementioned processes are conducted in a classical manner, that is, by stirring of the respective solutions or suspensions. Another intriguing approach to carry out chemical reactions that has recently gained more attention as an alternative to traditional liquid-phase-based reactions is mechanochemistry. Mechanochemistry in general refers to a way of promoting chemical reactions or chemical transformations by utilizing mechanical force and / or mechanical energy, and without the need for bulk dissolution of reactants. This art of chemical synthesis relies especially on methods which apply mechanical force, for example frictional, shear and / or impact force, including, but not limited to, (ball)-milling, extruding, grinding, vibration or acoustic mixing, and combinations thereof. A common sense about the definition of mechanochemistry that is referred to herein, as will be understood by a person skilled in the art, is given in, for example, Liu et al., Advanced Materials 2022, 34, 2108327 or Do et al., ACS Central Science 2017, 3, 13-19. Surprisingly, it has been found that a mechanochemical approach is possible for conducting H-D exchange on organic molecules, even under mild conditions and low reaction temperatures, and without the need for bulk dissolution of reactants, so that the present invention makes it possible to achieve one or more of the following advantages: decrease in the extent of side reactions, high conversation and H-D exchange rates, fast reaction times, and high environmental compatibility due to reduced amounts of solvents and improved recyclability of process components.

[0014] The present invention therefore provides a method for deuterating an organic compound, the method comprising the following steps:

[0015] (a) providing a composition comprising the organic compound to be deuterated and a deuterium source; and

[0016] (b) subjecting the composition to a mechanochemical treatment in the presence of a catalyst.

[0017] Deuteration of an organic compound means the substitution of at least one hydrogen atom that is bound to a carbon atom of an organic compound with a deuterium atom, which substitution is also referred to herein as “H-D exchange”. Accordingly, the terms “H-D exchange method” and “deuteration method” both are understood to mean methods which aim at substituting at least one hydrogen atom in a compound with a deuterium atom to obtain a deuterated compound.

[0018] The term “deuterated compound” as used herein corresponds to a compound, in which at least one hydrogen atom is replaced by a deuterium atom and in which the abundance of deuterium at each deuterated position of the compound is higher than the natural abundance of deuterium, which is about 0.015%. To become a “deuterated compound”, a compound / precursor has to undergo a deuterium enrichment via a deuteration method. It is well recognized that a “deuterated compound” is indeed a mixture of various isotopomers, but the singular term is applied for the sake of conciseness. In accordance with the present invention, the deuteration degree corresponds to the number of deuterium atoms in a compound based on the total number of deuterium atoms and protium atoms in the compound in %, as follows:

[0019] Deuteration degree (%) = (ND * 100) I (Np + ND) where:

[0020] ND is the number of deuterium atoms in the compound Np is the number of deuterium and protium atoms in the compound.

[0021] The deuteration degree can be determined or measured by1H-NMR or gas chromatography-mass spectrometry (GC-MS), or high-performance liquid chromatography-mass spectrometry (HPLC-MS), which are all standard methods known to a person skilled in the art.

[0022] Unless specified otherwise herein, the term hydrogen should be understood to design the protium isotope of hydrogen, which accounts for more than 99.98% of the natural occurring hydrogen in the oceans.

[0023] As used herein, and in line with the general meaning and definition of mechanochemistry as referred to above, “mechanochemical treatment” should be understood to mean conduction of a chemical reaction, here, deuteration via H-D exchange, in a setup, where mechanical energy is dissipated on the reaction mixture as the predominant, but not necessarily the only, form of energy input. Typical examples of methods capable of providing a setup, where mechanical energy is dissipated on the reaction mixture include, without being limited thereto, milling such as ball milling, grinding, extruding, mixing such as vibrational mixing or resonance acoustic mixing, and the like, which methods apply mechanical force such as frictional, shear and / or impact force on the reactants.

[0024] Consequently, the term “mechanochemical device” should be understood to mean any device, apparatus or equipment capable of conducting such mechanochemical treatment by generating mechanical force and / or energy to be dissipated on the reaction mixture. Typical devices in this sense include, without being limited thereto, milling devices such as ball, shaker, roller or planetary mills, extruders, mixing devices such as (resonance) acoustic mixers or vibrational mixers, grinding devices, and the like.

[0025] Providing the composition in step a) preferably comprises mixing of the individual components, i.e. , the organic compound to be deuterated, the deuterium source, etc. The mixing can be carried out in any feasible way known to a person skilled in the art. The organic compound may be dissolved or partially dispersed in the composition, which may be due to the fact that deuterium source used is liquid, or because a solvent may be additionally added. Accordingly, the composition is preferably provided in the form of a solution or a suspension, more preferably in the form of a suspension, in particular in case the organic compounds has low solubility in common solvents and / or the deuterium source. However, as explained above, the mechanochemical approach applied in the present invention advantageously does not require for bulk dissolution of reactants and therefore allows for reduced amounts of solvents and renders high temperatures to boost the solubility unnecessary.

[0026] To enable the H-D exchange for deuteration of the organic compound, a deuterium source which is able to provide one or more deuterium atoms for hydrogen substitution has to be provided in the composition. The deuterium source is preferably selected from deuterated hydrocarbons, deuterated ethers, deuterated chlorocarbons, deuterated aprotic compounds, and deuterated protic compounds. More preferably the deuterium source is selected from deuterium oxide (D2O), deuterated benzenes (benzene-dn), particularly benzene-de, deuterated toluenes (toluene-dn), particularly toluene- ds and toluene-ds, deuterated xylenes (xylene-dn), particularly xylene-dw, deuterated dimethyl sulfoxide (DMSO-dn), particularly DMSO-de, deuterated acetones (acetone-dn), particularly acetone-de, deuterated alcohols, preferably CD3OD and EtOH-dn, and CDCI3, and mixtures thereof. Even more preferably, the deuterium source is selected from D2O, deuterated benzenes (benzene-dn), deuterated toluenes (toluene-dn), deuterated xylenes (xylene- dn), CD3OD and EtOH-dn, and mixtures thereof. Most preferably, the deuterium source is deuterium oxide (D2O) due to its comparably low costs. Deuterium oxide in the sense of the invention also refers to heavy water. Further preferably, the deuterium source has a deuterium enrichment of more than 10 mol%, preferably more than 50 mol%, more preferably more than 70 mol%, and most preferably more than 90 mol%, in order to increase the H-D exchange rate. A deuterium enrichment of more than 10 mol% is understood to mean that more than 10 mol% of all hydrogen atoms are substituted by deuterium, and so on. Thus, in a further preferred embodiment, for the H-D exchange the deuterium source is selected from deuterated hydrocarbon solvents, deuterated ether solvents, deuterated chlorocarbon solvents, deuterated aprotic solvents, and deuterated protic solvents, for example deuterium oxide, deuterated benzenes, deuterated toluenes, deuterated xylenes, deuterated dimethyl sulfoxide, deuterated acetones, deuterated alcohols, and CDCh, having a deuterium enrichment of more than 10 mol%, preferably more than 50 mol%, more preferably more than 70 mol%, and most preferably more than 90 mol%.

[0027] The amount of the deuterium source may depend on the type of organic compound and its amount in the composition. Preferably according to the invention, the amount of the deuterium source in the composition provided in step a) is from 1 to 98 weight percent (“wt.%”), more preferably 1 to 95 wt.%, even more preferably 1 to 75 wt.%, even more preferably 1 to 65 wt.%, even more preferably 1 to 55 wt.%, still more preferably 1 to 45 wt.%, still more preferably 1 to 35 wt.%, particularly preferably 1 to 25 wt.%, more particularly preferably 1 to 15 wt.% and most preferably 1 to 5 wt.%, each based on a total weight of the deuterium source and the organic compound in the composition.

[0028] The mechanochemical treatment in step b) is not limited, as long as it is capable of conducting the deuteration of the organic compound via H-D exchange in a setup, where mechanical energy is dissipated on the composition as the predominant, but not necessarily the only, form of energy input. For subjecting the composition to the mechanochemical treatment in step b), any method known by a person skilled in the art that applies mechanical force, such as frictional, shear and / or impact force, to thereby provide a setup where mechanical energy is dissipated on the composition, may be employed as desired. Exemplary methods for conducting the mechanochemical treatment in step b) include, but are not limited to, milling, such as ball-milling, grinding, extruding, or mixing, such as vibrational mixing or (resonance) acoustic mixing, of the composition in order to apply mechanical force and / or energy. Devices for carrying out such mechanochemical treatment, which generate mechanical force and / or energy to be dissipated on the composition, are known to a person skilled in the art and include, for example, milling devices such as ball, shaker, roller and planetary mills, extruders, mixing devices such as (resonance) acoustic mixers or vibrational mixers, grinding devices such as manual grinders, without being limited thereto.

[0029] The mechanochemical treatment of the composition for conducting the deuteration of the organic compound may allow for reducing the amount of solvent and may render high temperatures to boost the solubility of the organic compound and high reaction temperatures, which may increase the formation of side reactions, unnecessary, but high conversation and H-D exchange rates and fast reaction rates may nevertheless be achieved.

[0030] In a preferred embodiment of the invention, the mechanochemical treatment in step b) comprises milling, in particular ball-milling, grinding, extruding, or mixing, in particular vibrational mixing or (resonance) acoustic mixing, or a combination of one or more thereof, of the composition provided in step a), and more preferably comprises milling or mixing, or a combination thereof, and particularly preferably comprises ball-mixing or (resonance) acoustic mixing, or a combination thereof. The conditions at which those methods are carried out for the mechanochemical treating can be selected by a person skilled in the art without difficulties based on general technical knowledge, and may vary depending on the method applied.

[0031] In a further preferred embodiment, the mechanochemical treatment in step b) is carried out using a mechanochemical device, which is configured to generate mechanical force and / or energy to be dissipated on the composition, the mechanochemical device being more preferably selected from milling devices such as ball mills, shaker mills, roller mills or planetary mills, extruders, mixing devices such as resonance acoustic mixers or vibrational mixers, and grinding devices, and a combination of one or more thereof. The duration of the mechanochemical treatment in step b) is not particularly limited, as long as sufficient energy to promote chemical synthesis is created, and may be set as desired mainly depending on the method and / or device employed. In order to further increase high conversation rates and H-D exchange rates, however, it may be preferable according to an embodiment of the invention to carry out mechanochemical treatment in step b) for at least 30 minutes, more preferably for at least 1 h. From a viewpoint of process efficiency, however, a duration of the mechanochemical treatment of 48 h or less may be preferably, more preferably 24 h or less. Therefore, in a particularly preferred embodiment the mechanochemical treatment in step b) is carried out for a period of 30 min to 48 h, even more preferably 1 h to 24 h, which is an optimum range in view of conversation rates and process efficiency. In an even more preferred embodiment, the mechanochemical treatment in step b) comprises milling, in particular ball-milling, grinding, extruding, or mixing, in particular vibrational mixing or (resonance) acoustic mixing, or a combination of one or more thereof, for at least 30 minutes, preferably for at least 1 h, and preferably for 48 h or less, more preferably 24 h or less.

[0032] The method according to the invention advantageously does not necessarily require any heating, for example, to dissolve the organic material and / or to initiate and promote the H-D exchange, which in particular means that the method of the invention, and in particular the mechanochemical treatment, can be carried out at relatively low temperatures, in particular ambient (room) temperature (23 ± 2 °C). Therefore, in a preferred embodiment the method for deuterating an organic compound according to the invention does not comprise any step of heating the composition, preferably not any heating step at all. However, moderate heating in order to further increase conversation and H-D exchange rates and the reaction time may nevertheless be applied. Therefore, in another preferred embodiment of the invention, the mechanochemical treatment in step b) is carried out under a controlled temperature in the range of 20°C to 120°C, more preferably 20°C to 80°C, even more preferably 20°C to 60°C. Within such temperature range, conversation and H-D exchange rates and reaction time may be further increased, while side reactions and formation of unwanted side products may still be prevented. In another particularly preferred embodiment, the mechanochemical treatment in step b) comprises milling, in particular ballmilling, grinding, extruding, or mixing, in particular vibrational mixing or (resonance) acoustic mixing, or a combination of one or more thereof, under a controlled temperature in the range of 20°C to 120°C, more preferably 20°C to 80°C, even more preferably 20°C to 60°C.

[0033] In a further preferred embodiment of the invention, the mechanochemical treatment in step b) is carried out under a condition of pressure of 1 bar or more, more preferably in the range of 1 bar to 5 bar, in order to further increase conversation and H-D exchange rates while preventing side reactions and formation of unwanted side products. In an even more preferred embodiment, the mechanochemical treatment in step b) comprises milling, in particular ball-milling, grinding, extruding, or mixing, in particular vibrational mixing or (resonance) acoustic mixing, or a combination of one or more thereof, under conditions of pressure of 1 bar or more, more preferably in the range of 1 bar to 5 bar.

[0034] Each of the above conditions for the mechanochemical treatment, i.e. time, temperature and pressure, may be selected by a person skilled in the art as desired within the above-defined ranges, depending on, for example, the method and / or mechanochemical device employed for mechanochemically treating the composition, or the organic compound to be deuterated.

[0035] In line with the above, the mechanochemical device to be employed for the mechanochemical treatment in step b) may be equipped with temperature and / or pressure control capabilities.

[0036] According to the invention, the mechanochemical treatment of the composition in step b) is conducted in the presence of a catalyst. The catalyst is preferably a metal catalyst, and more preferably comprises or is selected from platinum, palladium, rhodium, ruthenium, iridium, nickel, cobalt, oxides thereof, complexes thereof, or a combination of one or more thereof. Even more preferably, the metal catalyst comprises or is selected from platinum, palladium, oxides thereof, complexes thereof, or combinations thereof, and most preferably comprises or is selected from platinum, platinum oxides or platinum complexes. The expression “in the presence of” indicates that the catalyst not necessarily has to be added and / or mixed to the composition as a separate component in step a), for example in solid form such as a powder, before the composition is subjected to the mechanochemical treatment in step b). According to one embodiment of the invention, the catalyst may part of the mechanochemical device itself which is employed to carry out the mechanochemical treating. For example, at least parts of the surface of the mechanochemical device or its equipment may bear the catalyst either in the form of a coating (for example, milling balls or jars surface-coated with platinum) or by being made of the catalyst material (for example solid platinum milling balls or jars).

[0037] According to another embodiment, which is preferable according to the invention, the catalyst is added to the composition as a separate component, preferably in solid form, and more preferably before the composition is subjected to the mechanochemical treatment. The timing of the addition of the catalyst is not critical, as long as it is ensured that the mechanochemical treatment of the composition is conducted in the presence of the catalyst. Preferably according to this embodiment, the catalyst is either employed in pure form, including oxides, complexes, blends thereof, for example, a powder or the like of the respective metal or metal oxide, or deposited on an inert solid support phase, that is, a solid phase that is stable under the conditions of the mechanochemical treatment and preferably is not soluble in the composition. The solid phase may be any suitable material. Preferred examples of the inert solid support phase are, without being limited thereto, carbons such as activated carbon or carbon black, aluminium oxides, titanium oxides, silicon oxides, silicates, or polymers. Particularly preferably, the inert solid phase is selected form carbons. Depositing the catalyst on an inert solid support phase provides the possibility of tuning the properties of the catalyst and, therefore, is preferable according to the present invention.

[0038] Particularly preferably, the catalyst is selected from platinum on carbon (Pt / C), palladium on carbon (Pd / C), platinum(IV) oxide on carbon (PtC / C), palladium(ll) hydroxide on carbon (Pd(OH)2 / C), palladium^ I) chloride on carbon (PdCl2 / C), or a combination thereof. A preferred catalyst combination is a combination of Pt / C and Pd / C, preferably a mixture of 10:1 to 1 :2 of Pt / C to Pd / C, more preferably 7:1 to 1 :1 , especially 5:1 to 1 :1 , measured by weight. Very particularly preferably, the catalyst is selected from Pt / C and PtO2 / C.

[0039] The content of the metal on the carbon of the catalyst according to this embodiment is preferably 1 to 15% by weight, for example 5% by weight, or 10 % by weight, based on the total weight of the catalyst.

[0040] The molar ratio of the catalyst (that is, the metal catalyst, omitting the solid support phase of the catalyst if present) to the compound to be deuterated is preferably from 1 :100 to 1 :1 , more preferably from 1 :70 to 1 :2, especially from 1 :30 to 1 :2. With a higher amount of catalyst, a higher reaction rate is observed, however, the costs increase concomitantly.

[0041] Catalysts, in particular metal catalysts, are often stored in a water-moist state. In one embodiment of the invention, the catalyst is dried before being used and added to the composition in order to remove water (H2O) that may compromise deuteration. Drying of the catalyst may be carried out at a temperature of 20 °C to 200 °C and for a period of at least 12 hours, preferably at reduced pressure, in particular below 100 mbar, and further preferably under inert gas such as nitrogen or argon.

[0042] In another embodiment of the invention, in particular if the catalyst has been stored in a deuterated liquid, in particular D2O, the catalyst is not dried before being used, but preferably the catalyst is employed and added to the composition in its wetted or moist state, because the deuterated liquid advantageously may act as a deuterium source. In that case, the deuterated liquid wetting the catalyst may either be the only deuterium source provided in the composition in step a), and may be selected from any one of the deuterium sources mentioned above, or may supplement an additional deuterium source mentioned above that is also provided in the composition in step a). In case both, the deuterated liquid wetting the catalyst and an additional deuterium source, are provided in the composition in step a), the deuterated wetting liquid and the additional deuterium source preferably are of the same compound, and more preferably are both D2O. Preferably according to this embodiment, a catalyst wetted with more than 5% by weight, more preferably more than 10% by weight, for example 50% by weight, of the deuterated liquid, in particular D2O, is employed.

[0043] According to a preferred embodiment of the invention, the composition in step a) further comprises at least one additive to improve deuteration / H-D exchange rates and / or prevent formation of side-products. The at least one additive may be mixed with the other components to provide the composition in step a). Preferably, the at least one additive is selected from hydrogen (that is, H2, D2 and / or HD), alcohols, in particular isopropanol (iPrOH), metal salts and metal hydride salts. The metal hydride salts preferably have the formula MxM’yHn (also known as “complex metal hydrides”), wherein M is an alkali or earth-alkali metal cation or cation complex, preferably sodium or lithium, and M’ is a metal or metalloid, preferably of group 13 elements (IIIPAC), more preferably boron or aluminium, but also include simple metal hydrides (y = 0), with preferred examples being NaH and CaH2. Borohydride salts are particularly preferred metal hydride salts.

[0044] The metal of the metal salt is preferably selected from metals of the alkali and earth-alkali series, boron, aluminium, copper, nickel and cobalt. The salts of the metal salts may be, for example, the chlorides, bromides, iodides, nitrates, sulfates, carboxylic acid salts such as acetates, propionates or pivalates, without being limited thereto.

[0045] More preferably according to this embodiment, the at least one additive is selected from hydrogen (H2, D2 and / or HD), alcohols and metal hydride salts. Particularly preferably according to this embodiment, the additive is selected from hydrogen (H2, D2, and / or HD), borohydride salts, and iPrOH, of which iPrOH is most preferred.

[0046] The amount of the at least one additive may depend on the deuterium source and the organic compound. Preferably, the at least one additive is used in a molar ratio of additive to organic compound of 1 :2 to 1 : 100, preferably 1 :2 to 1 :50, in particular 1 :2 to 1 :30.

[0047] According to a further preferred embodiment of the invention, the composition in step a) further comprises a solvent to improve solubility of the organic compound. Thus, a suitable solvent is a solvent in which the organic compound to be deuterated is at least partly soluble. The solvent may be mixed with the other components to provide the composition in step a). Preferably, the solvent is selected from aromatic solvents, ethers, alcohols, alkanes, cycloalkanes, amides, esters, and mixtures thereof. More preferably, the solvent is selected from alkanes and cycloalkanes, and mixtures thereof, and particularly preferably from cycloalkanes comprising at least one ring having 5 or more aliphatic carbon atoms. Preferred examples of suitable cycloalkanes are cyclohexane, methyl cyclohexane and fused cycloalkanes like decalin (cis- or trans-decalin and mixture thereof).

[0048] Preferably, the solvent is employed in such an amount that the organic compound dissolves at least partially; measured in volume preferably in a ratio of deuterium source:solvent of 2:1 to 1 :50, preferably 1 :1 to 1 :30, especially 1 : 1 .5 to 1 :30, most particularly at 1 : 1 .5 to 1 : 10. The optimum amount here depends on the solubility of the organic compound.

[0049] According to a further preferred embodiment of the invention, the composition in step a) further comprises a grinding aid in order to improve conversation rates / H-D exchange rates. The grinding aid preferably is a solid and more preferably is selected from carbons such as activated carbon or carbon black, aluminium oxides, titanium oxides, silicon oxides, silicates, and combinations thereof.

[0050] The grinding aid according to this embodiment may be added to the composition before or during the mechanochemical treatment, and preferably is added in a weight not exceeding a sum of the weight of the organic compound, the deuterium source and the catalyst, preferably in a weight less than 50% of said sum, more preferably in a weight less than 30% of said sum, in order to further improve process efficiency.

[0051] The organic compound to be deuterated can be any organic compound wherein the term organic compound is well known to the skilled person. Preferred organic compounds to be deuterated are defined elsewhere within the present application. The organic compound to be deuterated is preferably a compound that is suitable for being used in an electronic device, in particular an organic electroluminescent (EL) device such as an OLED, or is a precursor of such a compound. Depending on the substitution, the compounds can be used in different functions and layers. According to the present invention, the organic compound to be deuterated should be understood to also include organometallic compounds, in particular organometallic compounds containing a metal atom selected from copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, indium, palladium, platinum, silver, gold or europium, which have at least one heteroaromatic ring system. Preferably, the organometallic compounds are metal chelate complexes, in particular with at least one heteroaromatic ring system as chelating ligand for the metal.

[0052] An electronic device in the sense of the present invention is a device comprising anode, cathode and at least one functional layer containing at least one organic compound. The device may also contain inorganic materials or layers which are composed partly or entirely of inorganic materials.

[0053] The electronic device is preferably an organic electroluminescent (EL) devices comprising cathode, anode and at least one emitting layer as the functional layer. Apart from cathode, anode and emitting layer, organic electroluminescent devices may comprise further functional layers selected from, for example, in each case one or more hole injection layers (HIL), hole transport layers (HTL), hole blocker layers (HBL), electron transport layers (ETL), electron injection layers (EIL), electron blocker layers, exciton blocker layers (EBL), interlayers, charge generation layers (IDMC 2003, Taiwan; Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic EL Device Having Charge Generation Layer) and / or organic or inorganic p / n junctions.

[0054] Preferred examples of the organic electroluminescent (EL) device are organic light emitting diodes (OLEDs), organic integrated circuits (OlCs), organic fieldeffect transistors (OFETs), organic thin-film transistors (OTFTs), organic lightemitting transistors (OLETs), organic solar cells (OSCs), dye-sensitized organic solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs), organic laser diodes (O-lasers) and organic plasmon emitting devices, of which organic light emitting diodes (OLEDs) are especially preferred.

[0055] So, more preferably, the organic compound to be deuterated is an organic functional material which can be employed for the production of functional layers of electronic devices. Organic functional materials are generally the organic materials which are introduced in one or more functional layer between the anode and the cathode of an electronic device. The organic functional material as the organic compound to be deuterated is preferably selected from fluorescent emitters, phosphorescent emitters, host or matrix materials, electron injection materials, electron transport materials, electron blocking materials, wide band gap materials, hole injection materials, hole transport materials, hole blocking materials, exciton blocking materials, n- dopants and p-dopants.

[0056] Even more preferably, the organic compound to be deuterated is an organic functional material which is selected from the group of matrix materials, phosphorescent emitters and hole transport materials, still more preferably a matrix materials and hole transport materials, and most preferably a matrix material.

[0057] The matrix material to be deuterated can preferably be a hole transporting matrix material, and electron transporting matrix material or a bipolar matrix material, more preferably the matrix material is a hole transporting or bipolar matrix material, wherein bipolar matrix materials contain both electron transporting (e.g. triazinyl- pyrimidyl- dibenzothiophenyl- or dibenzofuranyl groups) and hole transporting groups (e.g. carbazolyl- biscarbazolyl-, indenocarbazolyl- or indolocarazolyl-groups).

[0058] In one very preferred embodiment, the matrix material to be deuterated is a hole transporting matrix material. Very preferred hole transporting matrix materials to be deuterated are carbazoles and biscarbazoles. The term “phosphorescent emitter” typically refers to compounds in which the emission of light occurs through a spin-forbidden transition, e.g., a transition from an excited triplet state or a state with a higher spin quantum number, e.g., a quintet state.

[0059] Examples of fluorescent emitters which can be employed as the organic compound to be deuterated are aromatic anthracenamines, aromatic anthracenediamines, aromatic pyrenamines, aromatic pyrenediamines, aromatic chrysenamines or aromatic chrysenediamines. An aromatic anthracenamine is taken to mean a compound in which one diarylamino group is bonded directly to an anthracene group, preferably in the 9-position. An aromatic anthracenediamine is taken to mean a compound in which two diarylamino groups are bonded directly to an anthracene group, preferably in the 9,10-position. Aromatic pyrenamines, pyrenediamines, chrysenamines and chrysenediamines are defined analogously thereto, where the diarylamino groups are preferably bonded to the pyrene in the 1 -position or in the 1 ,6-position. Further preferred emitters are indenofluorenamines or indenofluorenediamines, for example in accordance with WO 2006 / 108497 or WO 2006 / 122630, benzoindenofluorenamines or benzoindenofluorene- diamines, for example in accordance with WO 2008 / 006449, and dibenzo- indenofluorenamines or dibenzoindenofluorenediamines, for example in accordance with WO 2007 / 140847, and the indenofluorene derivatives containing condensed aryl groups which are disclosed in WO 2010 / 012328. Still further preferred emitters are benzanthracene derivatives as disclosed in WO 2015 / 158409, anthracene derivatives as disclosed in WO 2017 / 036573, fluorene dimers connected via heteroaryl groups like in WO 2016 / 150544 or phenoxazine derivatives as disclosed in WO 2017 / 028940 and WO 2017 / 028941. Preference is likewise given to the pyrenarylamines disclosed in WO 2012 / 048780 and WO 2013 / 185871. Preference is likewise given to the benzoindenofluorenamines disclosed in WO 2014 / 037077, the benzofluorenamines disclosed in WO 2014 / 106522 and the indenofluorenes disclosed in WO 2014 / 111269 or WO 2017 / 036574, WO 2018 / 007421. Also preferred are the emitters comprising dibenzofuran or indenodibenzofuran moieties as disclosed in WO 2018 / 095888, WO 2018 / 095940, WO 2019 / 076789, WO 2019 / 170572. Preference is likewise given to boron derivatives as disclosed, for example, in WO 2015 / 102118, CN108409769, CN107266484, WO2017195669 or US2018069182.

[0060] Examples of suitable matrix materials for fluorescent compounds which can be employed as the organic compound to be deuterated include materials of various substance classes. Preferred matrix materials are selected from the classes of oligoaryls (e.g., 2,2’,7,7’-tetraphenylspirobifluorene according to EP 676461 or dinaphthylanthracene), especially oligoaryls with fused aromatic groups, oligoarylenevinylenes (e.g. e.g. DPVBi or spiro-DPVBi according to EP 676461 ), the polypodal metal complexes (e.g. according to WO 2004 / 081017), the hole-conducting compounds (e.g. e.g. according to WO 2004 / 058911 ), the electron-conducting compounds, in particular ketones, phosphine oxides, sulfoxides, etc. (for example according to WO 2005 / 084081 and WO 2005 / 084082), the atropisomers (for example according to WO 2006 / 048268), the boronic acid derivatives (for example according to WO 2006 / 117052) or the benzanthracenes (for example according to WO 2008 / 145239). Particularly preferred matrix materials are selected from the classes of oligoarylenes with naphthalene, anthracene, benzanthracene and / or pyrene or atropisomers of these compounds, the oligoarylenevinylenes, the ketones, the phosphine oxides and the sulfoxides. Very particularly preferred matrix materials are selected from the classes of oligoarylene comprising anthracene, benzanthracene, benzophenanthrene and / or pyrene or atropisomers of these compounds. In the context of the present invention, an oligoarylene is to be understood as a compound in which at least three aryl or arylene groups are linked together. Further preferred are the anthracene derivatives disclosed in WO 2006 / 097208, WO 2006 / 131192, WO 2007 / 065550, WO 2007 / 110129, WO 2007 / 065678, WO 2008 / 145239, WO 2009 / 100925, WO 2011 / 054442 and EP 1553154, the anthracene derivatives disclosed in EP 1749809, EP 1905754 and US 2012 / 0187826, the pyrene compounds disclosed in WO 2015 / 158409, the benzanthracenylanthracene compounds disclosed in WO 2017 / 025165, and the phenanthrylanthracenes disclosed in WO 2017 / 036573.

[0061] Suitable phosphorescent emitting compounds (= triplet emitters) which can be employed as the organic compound to be deuterated are especially compounds which, when suitably excited, emit light, preferably in the visible region, and also contain at least one atom of atomic number greater than 20, preferably greater than 38, and less than 84, more preferably greater than 56 and less than 80. Preference is given to using, as phosphorescent emitting compounds, compounds containing copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold or europium, especially compounds containing iridium, platinum or copper. In the context of the present invention, all luminescent indium, platinum or copper complexes are considered to be phosphorescent emitting compounds.

[0062] Examples of the above-described emitting compounds, which may be premixed with matrix materials, can be found in applications WO 00 / 70655, WO 01 / 41512, WO 02 / 02714, WO 02 / 15645, EP 1191613, EP 1191612, EP 1191614, WO 05 / 033244, WO 05 / 019373 and US 2005 / 0258742. In general, all phosphorescent complexes as used for phosphorescent OLEDs according to the prior art and as known to those skilled in the art in the field of organic electroluminescent devices are suitable for being employed as the organic compound to be deuterated.

[0063] Examples of matrix materials for phosphorescent emitters which can be employed as the organic compound to be deuterated are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones, e.g. according to WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680, triarylamines, carbazole derivatives, e.g. CBP (N,N- biscarbazolylbiphenyl) or according to WO 2005 / 039246, US 2005 / 0069729, JP 2004 / 288381 , EP 1205527, WO 2008 / 086851 or WO 2013 / 041176, biscarbazoles, indolo_,carbazole derivatives, e.g. e.g. according to WO 2007 / 063754 or WO 2008 / 056746, indenocarbazole derivatives, e.g. according to WO 2010 / 136109, WO 2011 / 000455, WO 2013 / 041176 or WO 2013 / 056776, azacarbazole derivatives, e.g. according to EP 1617710, EP 1617711 , EP 1731584, J P 2005 / 347160, bipolar matrix materials, e.g. according to WO 2007 / 137725, silanes, e.g. according to WO 2005 / 111172, azaborols or boronic esters, e.g. according to WO 2006 / 117052, triazine derivatives, e.g. according to WO 2007 / 063754, WO 2008 / 056746, WO 2010 / 015306, WO 2011 / 057706, WO 2011 / 060859 or WO 2011 / 060877, zinc complexes, e.g. according to EP 652273 or WO 2009 / 062578, diazasilol or tetraazasilol derivatives, e.g. according to WO 2010 / 054729, diazaphosphole derivatives, e.g. according to WO 2010 / 054730, bridged carbazole derivatives, e.g. according to WO 2011 / 042107, WO 2011 / 060867, WO 2011 / 088877 and WO 2012 / 143080, triphenylene derivatives, e.g. according to WO 2012 / 048781 , lactams, e.g. according to WO 2011 / 116865 or WO 2011 / 137951 , or dibenzofuran derivatives, e.g. according to WO 2015 / 169412, WO 2016 / 015810, WO 2016 / 023608, WO 2017 / 148564 or WO 2017 / 148565. Likewise, another phosphorescent emitter, which emits shorter wavelengths than the actual emitter, can be present in the mixture as a cohost or a compound that does not participate or does not participate to a significant extent in charge transport, as described, for example, in WO 2010 / 108579.

[0064] Suitable charge transport materials, such as those that can be used in the hole injection or hole transport layer or in the electron barrier layer or in the electron transport layer of the electronic device, in addition to the deuterated compounds, are for example those mentioned in Y. Shirota et al, Chem. Rev. 2007, 107(4), 953-1010, or other materials as used in these layers according to the prior art.

[0065] Hole transporting materials that are preferably used in a hole transport layer, an electron blocker layer or a hole injection layer of an organic electroluminescent (EL) device, and which can be employed as the organic compound to be deuterated, include, in particular, indenofluorenamine derivatives (e.g., according to WO 06 / 122630 or WO 06 / 100896), the amine derivatives disclosed in EP 1661888, hexaazatriphenylene derivatives (e.g. according to WO 01 / 049806), amine derivatives with fused aromatics (for example according to US 5,061 ,569), the amine derivatives disclosed in WO 95 / 09147, monobenzoindenofluorenamines (for example according to WO 08 / 006449), dibenzoindenofluorenamines (for example according to WO 07 / 140847), Spirobifluorenamines (for example according to WO 2012 / 034627 or WO 2013 / 120577), Fluorenamines (for example according to WO 2014 / 015937, WO 2014 / 015938, WO 2014 / 015935 and WO 2015 / 082056), Spirodibenzopyranamines (for example according to WO 2013 / 083216), Dihydroacridine derivatives (for example according to WO 2012 / 150001 ), Spirodibenzofurans and Spirodibenzothiophenes (for example according to WO 2015 / 022051 , WO 2016 / 102048 and WO 2016 / 131521 ), Phenanthrendiarylamines (for example according to WO 2015 / 131976), Spirotribenzotropolones (for example according to WO 2016 / 087017), spirobifluorenes with meta-phenyldiamine groups (for example according to WO 2016 / 078738), spirobisacridines (for example according to WO 2015 / 158411 ), xanthenediarylamines (for example according to WO 2014 / 072017), and 9,10-dihydroanthracene spiro compounds with diarylamino groups according to WO 2015 / 086108.

[0066] Particularly preferred hole transport materials are spirobifluorenes substituted by diarylamino groups in the 4-position as hole-transporting compounds, in particular the use of those compounds claimed and disclosed in WO 2013 / 120577, and the use of spirobifluorenes substituted by diarylamino groups in the 2-position as hole-transporting compounds, in particular the use of those compounds claimed and disclosed in WO 2012 / 034627.

[0067] Electron transporting materials that are preferably used in an electron transport layer, a hole blocker layer or an electron injection layer of organic electroluminescent (EL), which can be employed as the organic compound to be deuterated, are all materials which are used as electron transport materials according to the state of the art. Particularly preferably are aluminium complexes, e.g. Alq3, zirconium complexes, e.g. Zrq4, lithium complexes, e.g. Liq, benzimidazole derivatives, triazine derivatives, pyrimidine derivatives, pyridine derivatives, pyrazine derivatives, quinoxaline derivatives, quinoline derivatives, oxadiazole derivatives, aromatic ketones, lactams, boranes, diazaphosphole derivatives and phosphine oxide derivatives. Other suitable materials include derivatives of the above compounds as disclosed in JP 2000 / 053957, WO 2003 / 060956, WO 2004 / 028217, WO 2004 / 080975, and WO 2010 / 072300.

[0068] As used herein, wide band gap materials will be understood to mean materials as disclosed in US 7,294,849, which are characterized in having a band gap of at least 3.5 eV. The term “band gap” denotes the distance between the energy level of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of a compound. Such systems exhibit especially advantageous performance data in electroluminescent devices. n-Dopants used according to the invention are preferably those organic electron donor compounds capable of reducing one or more of the other compounds in the mixture. Preferred examples of n-dopants which can be employed as the organic compound to be deuterated are W(hpp)4 und further electron-rich metal complexes according to WO 2005 / 086251 A2, P=N- compounds (e.g. WO 2012 / 175535 A1 , WO 2012 / 175219 A1 ), naphthylen- carbodiimides (e.g. WO 2012 / 168358 A1 ), fluorenes (e.g. WO 2012 / 031735 A1 ), radicals and biradicals (e.g. EP 1837926 A1 , WO 2007 / 107306 A1 ), pyridines (e.g. EP 2452946 A1 , EP 2463927 A1 ), N-heterocyclic compounds (e.g. WO 2009 / 000237 A1 ) and acridines and phenazines (e.g. US 2007 / 145355 A1 ). p-Dopants used according to the invention are preferably those organic electron acceptor compounds capable of oxidizing one or more of the other compounds in the mixture. Preferred examples of p-dopants which can be employed as the organic compound to be deuterated are F4-TCNQ, Fe-TNAP, NDP-2 (company Novaled), NDP-9 (company Novaled), quinones (e.g. EP 1538684 A1 , WO 2006 / 081780 A1 , WO 2009 / 003455 A1 , WO 2010 / 097433 A1 ), radialenes (e.g. EP 1988587 A1 , US 2010 / 102709 A1 , EP 2180029 A1 , WO 2011 / 131185 A1 , WO 2011134458 A1 , US 2012 / 223296 A1 ), S-containing transition metal complexes (e.g.

[0069] WO 2007 / 134873 A1 , WO 2008 / 061517 A2, WO 2008 / 061518 A2, DE 102008051737 A1 , WO 2009 / 089821 A1 , US 2010 / 096600 A1 ), bisimidazoles (e.g. WO 2008 / 138580 A1 ), phthalocyanines (e.g.

[0070] WO 2008 / 058525 A2), bora-tetraazapentalenes (e.g. WO 2007 / 115540 A1 ) fullerenes (e.g. DE 102010046040 A1 ) and main group halogenides (e.g. WO 2008 / 128519 A2).

[0071] All the materials mentioned above, which are all suitable as materials for organic electroluminescent (EL) devices such as OLEDs, can be employed as the organic compound to be deuterated by the method according to the invention.

[0072] According to a preferred embodiment of the present invention, the organic compound to be deuterated is not an organometallic compound. Particularly preferably, the organic compound to be deuterated is an aliphatic compound, a heteroaliphatic compound, an aromatic compound or a heteroaromatic compound. It is to be understood that the aliphatic compound, the heteroaliphatic compound, the aromatic compound and the heteroaromatic compound may be substituted by one or more substituents, like for example, halogens, alkyl groups, aryl groups, aromatic or heteroaromatic ring systems.

[0073] The aromatic compound is preferably a compound comprising an aromatic ring system, and more preferably is an aromatic ring system. The heteroaromatic compound is preferably a compound comprising a heteroaromatic ring system, and more preferably is a heteroaromatic ring system.

[0074] The following definitions of chemical groups apply for the purposes of the present application:

[0075] An aromatic ring system in the sense of this invention contains 6 to 60 aromatic C atoms in the ring system, preferably 6 to 40 C atoms, more preferably 6 to 20 C atoms. A heteroaromatic ring system in the sense of this invention contains 5 to 60 aromatic ring atoms, preferably 5 to 40 aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms are preferably selected from N, O and / or S. An aromatic or heteroaromatic ring system in the sense of this invention is intended to be taken to mean a system which does not necessarily contain only aryl or heteroaryl groups, but instead in which, in addition, a plurality of aryl or heteroaryl groups may be connected by a non-aromatic unit (preferably less than 10% of the atoms other than H), such as, for example, an sp3-hybridised C, Si, N or O atom, an sp2-hybridised C or N atom or an sp- hybridised C atom. Thus, for example, systems such as 9,9’-spirobifluorene, 9, 9’ -diarylfluorene, triarylamine, diaryl ether, stilbene, etc., are also intended to be taken to be aromatic ring systems in the sense of this invention, as are systems in which two or more aryl groups are connected, for example, by a linear or cyclic alkyl, alkenyl or alkynyl group or by a silyl group. Furthermore, systems in which two or more aryl or heteroaryl groups are linked to one another via single bonds are also taken to be aromatic or heteroaromatic ring systems in the sense of this invention, such as, for example, systems such as biphenyl, terphenyl or diphenyltriazine.

[0076] An aromatic or heteroaromatic ring system having 6 to 60, respectively 5 to 60, aromatic ring atoms, which may in each case also be substituted by radicals and which may be linked to the aromatic or heteroaromatic group via any desired positions, is taken to mean, in particular, groups derived from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene, truxene, isotruxene, spiro- truxene, spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo- 6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1 ,2-thiazole, 1 ,3- thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1 ,5-diazaanthracene, 2,7-diazapyrene, 2,3- diazapyrene, 1 ,6-diazapyrene, 1 ,8-diazapyrene, 4,5-diazapyrene, 4,5,9, 10-tetraazaperylene, pyrazine, phenazine, phenoxazine, phenothiazine, fluorubin, naphthyridine, azacarbazole, benzocarboline, phenanthroline,

[0077] 1 .2.3-triazole, 1 ,2,4-triazole, benzotriazole, 1 ,2,3-oxadiazole, 1 ,2,4- oxadiazole, 1 ,2,5-oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4- thiadiazole, 1 ,2,5-thiadiazole, 1 ,3,4-thiadiazole, 1 ,3,5-triazine, 1 ,2,4-triazine,

[0078] 1 .2.3-triazine, tetrazole, 1 ,2,4,5-tetrazine, 1 ,2,3,4-tetrazine, 1 ,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole, or combinations of these groups.

[0079] An aryl group in the sense of this invention contains 6 to 60 aromatic ring atoms, preferably 6 to 40 aromatic ring atoms, more preferably 6 to 20 aromatic ring atoms; a heteroaryl group in the sense of this invention contains 5 to 60 aromatic ring atoms, preferably 5 to 40 aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms are preferably selected from N, O and S. An aryl group or heteroaryl group here is taken to mean either a simple aromatic ring, i.e. benzene, or a simple heteroaromatic ring, for example pyridine, pyrimidine or thiophene, or a condensed (annellated) aromatic or heteroaromatic polycycle, for example naphthalene, phenanthrene, quinoline or carbazole. A condensed (annellated) aromatic or heteroaromatic polycycle in the sense of the present application consists of two or more simple aromatic or heteroaromatic rings condensed with one another.

[0080] An aryl or heteroaryl group, which may in each case be substituted by the above-mentioned substituents and which may be linked to the aromatic or heteroaromatic ring system at any desired positions, is taken to mean, in particular, groups derived from benzene, naphthalene, anthracene, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, fluoranthene, benzanthracene, benzophenanthrene, tetracene, pentacene, benzopyrene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6- quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1 ,2-thiazole, 1 ,3-thiazole, benzothiazole, pyridazine, benzo- pyridazine, pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine, naphthyridine, azacarbazole, benzocarboline, phenanthroline, 1 ,2,3-triazole, 1 ,2,4-triazole, benzotriazole, 1 ,2,3-oxadiazole, 1 ,2,4-oxadiazole, 1 ,2,5- oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4-thiadiazole, 1 ,2,5- thiadiazole, 1 ,3,4-thiadiazole, 1 ,3,5-triazine, 1 ,2,4-triazine, 1 ,2,3-triazine, tetrazole, 1 ,2,4,5-tetrazine, 1 ,2,3,4-tetrazine, 1 ,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole.

[0081] An aryloxy group in accordance with the definition of the present invention is taken to mean an aryl group, as defined above, which is bonded via an oxygen atom. An analogous definition applies to heteroaryloxy groups. An aliphatic compound in the sense of this invention is a straight-chain alkyl group having 1 to 40 C atoms or a branched or cyclic alkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, and a heteroaliphatic compound in the sense of this invention is a straight-chain alkyl group having 2 to 40 C atoms or a branched or cyclic alkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 3 to 40 C atoms, at least one of which is a heteroatom. The heteroatoms are preferably selected from N, O and S. Preferably, the (hetero)aliphatic compounds are taken to mean the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl or octynyl. An alkoxy or thioalkyl group having 1 to 40 C atoms is preferably taken to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio, i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio, n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio, trifluoromethylthio, pentafluoroethylthio, 2,2,2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio, pentenylthio, cyclopentenylthio, hexenylthio, cyclohexenylthio, heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio, heptynylthio or octynylthio.

[0082] The formulation that two radicals may form a ring with one another is, for the purposes of the present application, intended to be taken to mean, inter alia, that the two radicals are linked to one another by a chemical bond. This is illustrated by the following schemes:

[0083] Furthermore, however, the above-mentioned formulation is also intended to be taken to mean that, in the case where one of the two radicals represents hydrogen, the second radical is bonded at the position to which the hydrogen atom was bonded, with formation of a ring. This is illustrated by the following scheme:

[0084] Ri f i

[0085] When two radicals form a ring with one another, then it is preferred that the two radicals are adjacent radicals. Adjacent radicals in the sense of the present invention are radicals which are bonded to atoms which are linked directly to one another or which are bonded to the same atom.

[0086] In accordance with a further preferred embodiment, the organic compound to be deuterated is an aromatic ring system having 6 to 60 aromatic ring atoms, which may be substituted by one or more radicals RR. Preferred aromatic ring systems are selected from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, pery- lene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans- indenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, and combinations of these groups, which may be substituted by one or more radicals RR, where RRstands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CHO, CN, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)2Ar, N(R')2, N(Ar)2, NO2, Si(R )3, B(OR')2, OSO2R , a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , where in each case one or more non-adjacent CH2groups may be replaced by R C=CR , C=C, Si(R')2, Ge(R')2, Sn(R')2, C=O, C=S, C=Se, P(=O)(R ), SO, SO2, O, S or CONR and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R , or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ; where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R ;

[0087] Ar is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case also be substituted by one or more radicals R ;

[0088] R stands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, where in each case one or more non-adjacent CH2groups may be replaced by SO, SO2, O, S and where one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms.

[0089] In accordance with another further preferred embodiment, the organic compound to be deuterated is a heteroaromatic ring system having 5— 60 aromatic ring atoms, which may be substituted by one or more radicals RR, where RRis as defined above. Preferred heteroaromatic ring systems are selected from furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quino- line, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimi- dazole, pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1 ,2-thiazole, 1 ,3- thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1 ,5-diazaanthracene, 2,7-diazapyrene, 2,3- diazapyrene, 1 ,6-diazapyrene, 1 ,8-diazapyrene, 4,5-diazapyrene, 4,5,9, 10-tetraazaperylene, pyrazine, phenazine, phenoxazine, phenothiazine, fluorubin, naphthyridine, azacarbazole, benzocarboline, phenanthroline,

[0090] 1 .2.3-triazole, 1 ,2,4-triazole, benzotriazole, 1 ,2,3-oxadiazole, 1 ,2,4- oxadiazole, 1 ,2,5-oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4- thiadiazole, 1 ,2,5-thiadiazole, 1 ,3,4-thiadiazole, 1 ,3,5-triazine, 1 ,2,4-triazine,

[0091] 1 .2.3-triazine, tetrazole, 1 ,2,4,5-tetrazine, 1 ,2,3,4-tetrazine, 1 ,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole, or combinations of these groups, which may be substituted by one or more radicals RR, where RRis as defined above. Particularly preferred heteroaromatic ring systems are selected from dibenzofuran, dibenzothiophene, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzoquinoline, phenothiazine, phenoxazine, pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine, phenoxazine, phenothiazine and combinations of these groups, which may be substituted by one or more radicals RR, where RRis as defined above.

[0092] Further preferably, RRstands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CHO, CN, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)2Ar, N(R')2, N(Ar)2, NO2, Si(R )3, B(OR')2, OSO2R , a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , and wherein in each case one or more non-adjacent CH2groups may be replaced by R C=CR , C=C, Si(R )2, Ge(R')2, Sn(R')2, C=O, C=S, C=Se, P(=O)(R ), SO, SO2, O, S or CONR and wherein one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R , or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ; where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R .

[0093] More preferably, RRstands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CHO, CN, N(R')2, N(Ar)2, B(OR')2, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , and wherein one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R , or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ; where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R .

[0094] Even more preferably, RRstands on each occurrence, identically or differently, for H, D, F, CN, N(R')2, N(Ar)2, a straight-chain alkyl group having 1 to 40 C atoms or branched or a cyclic alkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , and wherein one or more H atoms may be replaced by D, F or CN, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R , where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R .

[0095] Still more preferably, RRstands on each occurrence, identically or differently, for H, D, a straight-chain alkyl group having 1 to 40 C atoms or branched or a cyclic alkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R , where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R .

[0096] Still more preferably, RRstands on each occurrence, identically or differently, for H, D, a straight-chain alkyl group having 1 to 40 C atoms or branched or a cyclic alkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may be substituted by one or more radicals R ;

[0097] Further preferably, R stands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, wherein in each of the aforementioned straight-chain or branched groups one or more non-adjacent CH2 groups may be replaced by SO, SO2, O, S and wherein one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms.

[0098] Further preferably, R stands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, wherein in each of the aforementioned straight-chain or branched groups one or more non-adjacent CH2 groups may be replaced by SO, SO2, O, S and wherein one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms.

[0099] More preferably, R stands on each occurrence, identically or differently, for H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or branched or cyclic alkyl group having 3 to 20 C atoms, wherein in each of the aforementioned straight-chain or branched groups one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms. The invention is also directed to deuterated compounds which are obtained by a deuteration method as described above.

[0100] All the organic functional materials mentioned above, which are all suitable as materials for organic electroluminescent (EL) devices such as OLEDs, can be deuterated by a method according to the present invention.

[0101] The deuterated materials can be used alone in a layer or be combined with one or more deuterated or non-deuterated material(s). Therefore, another aspect of the invention is a composition comprising a deuterated compound obtained by a method as defined above and at least one further compound.

[0102] The deuterated compounds according to the invention are suitable for use in an electronic device, in particular in an organic electroluminescent (EL) device such as an OLED. Depending on the substitution, the compounds can be used in different functions and layers.

[0103] Therefore, the invention is further directed to an electronic device comprising a deuterated compound obtained by a deuteration method as described above.

[0104] The electronic device is preferably an organic electroluminescent device comprising cathode, anode and at least one emitting layer, wherein at least one organic layer, which may be an emitting layer, hole transport layer, electron transport layer, hole blocking layer, electron blocking layer or another functional layer, comprises at least one deuterated compound according to the invention.

[0105] Apart from cathode, anode and emitting layer, organic electroluminescent devices may comprise further functional layers selected from, for example, in each case one or more hole injection layers (HIL), hole transport layers (HTL), hole blocker layers (HBL), electron transport layers (ETL), electron injection layers (EIL), electron blocker layers, exciton blocker layers (EBL), interlayers, charge generation layers (IDMC 2003, Taiwan; Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic EL Device Having Charge Generation Layer) and / or organic or inorganic p / n junctions. It should be noted, however, that not all of these layers necessarily have to be present. The organic electroluminescent device may contain one emitting layer, or it may contain several emitting layers. If several emitting layers are present, these preferably have a total of several emission maxima between 380 nm and 750 nm, so that white emission results overall, i.e. different emitting compounds that can fluoresce or phosphoresce are used in the emitting layers. In particular, systems with three emitting layers are preferred, with the three layers showing blue, green and orange or red emission (the principle structure is described, for example, in WO 2005 / 011013). The organic electroluminescent device according to the invention can also be a tandem OLED, in particular for white-emitting OLEDs.

[0106] A hole transport layer according to the present application is a layer having a hole-transporting function between the anode and emitting layer.

[0107] Hole injection layers and electron blocker layers are understood in the context of the present application to be specific embodiments of hole transport layers. A hole injection layer, in the case of a plurality of hole transport layers between the anode and emitting layer, is a hole transport layer which directly adjoins the anode or is separated therefrom only by a single coating of the anode. An electron blocker layer, in the case of a plurality of hole transport layers between the anode and emitting layer, is that hole transport layer which directly adjoins the emitting layer on the anode side.

[0108] An electron transport layer according to the present application is a layer having an electron-transporting function between the cathode and the emitting layer.

[0109] In accordance with a preferred embodiment, the organic electroluminescent device contains one hole transport layer comprising at least one deuterated hole-transport material obtained by a method according to the present invention. In accordance with a preferred embodiment, the organic electroluminescent device contains an organic layer, preferably one emitting layer, comprising at least one host or matrix material selected from deuterated aromatic or heteroaromatic compounds obtained by a method according to the present invention.

[0110] In accordance with a preferred embodiment, the organic electroluminescent device contains one emitting layer comprising at least one deuterated phosphorescent emitter obtained by a method according to the present invention.

[0111] In accordance with a preferred embodiment, the organic electroluminescent device contains one emitting layer comprising at least one deuterated fluorescent emitter obtained by a method according to the present invention.

[0112] Furthermore, the deuterated compound according to the invention can also be used in an electron transport layer and / or in a hole blocking layer and / or in a hole transport layer and / or in an exciton blocking layer.

[0113] Preferred cathodes of the organic electroluminescent device are metals with low work function, metal alloys or multilayer structures of different metals, e.g. alkaline earth metals, alkali metals, main group metals or lanthanides (e.g. Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Additionally suitable are alloys of an alkali or alkaline earth metal and silver, e.g. an alloy of magnesium and silver. In multilayer structures, other metals with a relatively high work function can be used in addition to the metals mentioned, e.g. Ag or Al, with combinations of the metals such as Ca / Ag, Mg / Ag or Ba / Ag usually being used. It may also be advantageous to introduce a thin interlayer of a material with a high dielectric constant between a metallic cathode and the organic semiconductor. Examples of suitable materials are alkali or alkaline earth metal fluorides, but also the corresponding oxides or carbonates (e.g. LiF, Li2O, BaF2, MgO, NaF, CsF, Cs2CO3, etc.). It is also possible to use lithium quinolinate (LiQ) for this purpose. The thickness of this layer is preferably between 0.5 and 5 nm. Preferred anodes of the organic electroluminescent device are materials with a high work function. Preferably, the anode has a work function of more than 4.5 eV against vacuum. Firstly, metals with a high redox potential, e.g. Ag, Pt or Au, are suitable for this purpose. Secondly, metal / metal oxide electrodes (e.g. AI / Ni / NiOx, Al / PtOx) may also be preferred. For some applications, at least one of the electrodes must be transparent or partially transparent to allow irradiation of the organic material (organic solar cell) or emission of light (OLED, O-laser). Preferred anode materials here are conductive mixed metal oxides. Indium tin oxide (ITO) or indium zinc oxide (IZO) are particularly preferred. Further preferred are conductively doped organic materials, in particular conductively doped polymers. In addition, the anode can also consist of two or more layers, for example an inner layer of ITO and an outer layer of a metal oxide, preferably tungsten oxide, molybdenum oxide or vanadium oxide.

[0114] Further preferably, the electronic device is an organic electroluminescent (EL) device selected from organic light emitting diodes (OLEDs), organic integrated circuits (OlCs), organic field-effect transistors (OFETs), organic thin-film transistors (OTFTs), organic light-emitting transistors (OLETs), organic solar cells (OSCs), dye-sensitized organic solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs), organic laser diodes (O-lasers) and organic plasmon emitting devices, but more preferably from organic light emitting diodes (OLEDs).

[0115] The device is structured, contacted and finally sealed to exclude harmful influences from water and air.

[0116] In the further layers of the organic electroluminescent device, all materials can be used as they are usually used according to the prior art. The skilled person can therefore use all materials known for organic electroluminescent devices in combination with the deuterated compounds as the aforementioned further compound without any inventive intervention. Also, the aforementioned compounds, in particular the aromatic or heteroaromatic compounds can be deuterated by the process according to the invention, in particular to improve their lifetime. Preferably, the organic electroluminescent device comprises one or more layers, which are deposited by a sublimation process. In this process, the materials are vapor-deposited in vacuum sublimation systems at an initial pressure of less than 10’5mbar, preferably less than 10’6mbar. However, it is also possible for the initial pressure to be even lower, for example less than 10’7mbar.

[0117] An organic electroluminescent device is also preferred, characterized in that one or more layers are coated using the OVPD (organic vapor phase deposition) process or with the aid of carrier gas sublimation. In this process, the materials are applied at a pressure between 10’5mbar and 1 bar. A special case of this process is the OVJP (Organic Vapour Jet Printing) process, in which the materials are applied directly through a nozzle and thus structured.

[0118] Further preferred is an organic electroluminescent device comprising one or more layers, which are produced from solution, such as by spin coating, or by any printing process, such as screen printing, flexographic printing, offset printing, LITI (Light Induced Thermal Imaging, thermal transfer printing), inkjet printing (inkjet printing) or nozzle printing. Soluble compounds are required for this, which can be obtained by suitable substitution, for example.

[0119] Hybrid processes are also possible, in which, for example, one or more layers of solution are applied and one or more further layers are vapor-deposited.

[0120] These processes are generally known to those skilled in the art and can be applied by them to organic electroluminescent devices containing the compounds of the invention without any inventive intervention.

[0121] The invention is described in more detail below with the help of examples which are not to be considered as limiting the scope of the invention. Examples:

[0122] Example 1 : Deuteration of biphenyl utilizing a ball-mill

[0123] Biphenyl (250 mg, 1 .6 mmol), catalyst wetted with 50% D2O (250 mg dry basis), optionally additional D2O, and optionally iPrOH are placed in a PFA- made cup that is mounted in a ball mill (Retsch MM500 ball mill). The catalysts and amounts of D2O and iPrOH applied in Samples 1-7 are listed in Table 1 below, such that the total amount of liquid stays constant.

[0124] Mechanochemical treatment is conducted for 60 min at room temperature applying a frequency of 35 Hz. Each sample mixture is then extracted from the cup with 10 mL THF, filtered, and evaporated to dryness, leaving 229 mg of biphenyl with a deuteration degree (“%D”) as listed in Table 1 . The deuteration degree in Example 1 and Examples 2 and 3 below is determined by GC-MS. The %D-value is elucidated by simulation of the isotope pattern of the M+-signal with an approximate error of ±5%. Example 2: Deuteration of biphenyl utilizing a resonance acoustic mixer

[0125] Biphenyl (1000 mg, 6.4 mmol), catalyst 5% Pt / C (1000 mg dry basis), 1000 pL D2O, and 300 pL iPrOH are placed in a PFA-made cup that is mounted in a resonance acoustic mixer (LabRAM II, Resodyn). Mechanochemical treatment is conducted for 60 min at room temperature applying 50g of accelerative force. The mixture is then extracted from the cup with 10 mL THF, filtered, and evaporated to dryness, leaving 957 mg of biphenyl with a deuteration degree of 50% adjudicated by GC-MS.

[0126] Example 3: Deuteration of 9-Phenylcarbazole utilizing a ball mill

[0127] 9-Phenylcarbazole (1000 mg, 4.11 mmol), catalyst 10% Pt / C (1000 mg dry basis), 1000 pL D2O, and 300 pL iPrOH are placed in a PFA-made cup that is mounted in a ball mill (Retsch MM500 ball mill). Mechanochemical treatment is conducted for 60 min at room temperature applying a frequency of 35 Hz. The mixture is then extracted from the cup with 10 mL THF, filtered, and evaporated to dryness, leaving 915 mg of 9-Ph-carbazole with a deuteration degree of 30% adjudicated by GC-MS.

Claims

Claims1 . A method for deuterating an organic compound, the method comprising: a) providing a composition comprising the organic compound to be deuterated and a deuterium source; and b) subjecting the composition to a mechanochemical treatment in the presence of a catalyst.

2. The method of claim 1 , characterised in that the deuterium source is selected from deuterated hydrocarbons, deuterated ethers, deuterated chlorocarbons, deuterated aprotic compounds, and deuterated protic compounds, and preferably is selected from deuterium oxide (D2O), deuterated benzenes (benzene-dn), deuterated toluenes (toluene-dn), deuterated xylenes (xylene-dn), deuterated dimethyl sulfoxide (DMSO-dn), deuterated acetones (acetone-dn), deuterated alcohols and CDCI3, and mixtures thereof.

3. The method according to claim 1 or 2, characterised in that the deuterium source has a deuterium enrichment of more than 10 mol%, preferably more than 50 mol%, more preferably more than 70 mol%, and most preferably more than 90 mol%.

4. The method according to one or more of claims 1 to 3, characterised in that the mechanochemical treatment comprises milling, in particular ball-milling, grinding, extruding, or mixing, in particular acoustic mixing or vibrational mixing, or a combination of one or more thereof, of the composition.

5. The method according to one or more of claims 1 to 4, characterised in that the mechanochemical treatment is carried out for at least 30 minutes.

6. The method according to one or more of claims 1 to 5, characterised in that the mechanochemical treatment is carried out under a controlled temperature in the range of 20°C to 120°C, and / or under a condition of pressure of 1 bar or more..

7. The method according to one or more of claims 1 to 6, characterised in that the catalyst is a metal catalyst, and preferably comprises platinum, palladium, rhodium, ruthenium, iridium, nickel, cobalt, oxides thereof, complexes thereof, or a combination of one or more thereof.

8. The method according to one or more of claims 1 to 7, characterised in that the composition further comprises at least one additive selected from hydrogen (H2, D2 and / or HD) , alcohols, metal salts, and metal hydride salts.

9. The method according to one or more of claims 1 to 8, characterised in that the composition further comprises a solvent, which preferably is selected from aromatic solvents, ethers, alcohols, alkanes, cycloalkanes, amides, esters, and mixtures thereof.

10. The method according to one or more of claims 1 to 9, characterised in that the composition further comprises a grinding aid, which is preferably selected from carbons, in particular activated carbon or carbon black, aluminium oxides, titanium oxides, silicon oxides, silicates, and combinations thereof.11 . The method according to claim 10, characterised in that grinding aid is added to the composition in a weight not exceeding a sum of the weight of the organic compound, the deuterium source and the catalyst, preferably in a weight less than 50% of said sum, more preferably in a weight less than 30% of said sum.

12. The method according to one or more of claims 1 to 11 , characterised in that the organic compound to be deuterated is an organic functional material, which preferably is selected from fluorescentemitters, phosphorescent emitters, host or matrix materials, electron injection materials, electron transport materials, electron blocking materials, wide band gap materials, hole injection materials, hole transport materials, hole blocking materials, exciton blocking materials, n-dopants and p-dopants.

13. The method according to one or more of claims 1 to 12, characterised in that the organic compound to be deuterated is selected from an aliphatic compound, a heteroaliphatic compound, an aromatic compound and a heteroaromatic compound.

14. The method according to one or more of claims 1 to 13, characterised in that the organic compound to be deuterated comprises an aromatic ring system preferably having 6 to 60 aromatic ring atoms, or an heteroaromatic ring system preferably having 5 to 60 aromatic ring atoms.

15. The method according to one or more of claims 1 to 14, characterised in that the organic compound to be deuterated is an aromatic compound selected from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, and combinations of these groups, which may be substituted by one or more radicals RR, whereRRstands on each occurrence, identically or differently, for H, D,F, Cl, Br, I, CHO, CN, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)2Ar, N(R')2, N(Ar)2, NO2, Si(R')3, B(OR')2, OSO2R , a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, wherein each of the aforementioned straight-chain or branched groups may be substituted by one or more radicals R , and wherein in each case one or more non-adjacent CH2groups may be replaced by R C=CR , C=C,Si(R')2, Ge(R')2, Sn(R')2, C=O, C=S, C=Se, P(=O)(R ), SO, SO2, 0, S or CONR and wherein one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R , or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R ; where two radicals RRmay form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R ;Ar is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case also be substituted by one or more radicals R ;R stands on each occurrence, identically or differently, for H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, wherein in each of the aforementioned straight-chain or branched groups one or more non-adjacent CH2 groups may be replaced by SO, SO2, O, S and wherein one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms16. The method according to one or more of claims 1 to 14, characterised in that the organic compound to be deuterated is a heteroaromatic compound selected from furans, benzofurans, isobenzofurans, dibenzofurans, thiophenes, benzothiophenes, isobenzothiophenes, dibenzothiophenes, pyrroles, indoles, isoindoles, carbazoles, indolocarbazoles, indenocarbazoles, pyridines, quinolines, isoquinolines, acridines, phenanthridines, benzo-5,6-quinolines, benzo- 6,7-quinolines, benzo-7,8-quinolines, phenothiazines, phenoxazines, pyrazoles, indazoles, imidazoles, benzimidazoles, naphthimidazoles, phenanthrimidazoles, pyridimidazoles, pyrazinimidazoles, quinoxalin- imidazoles, oxazoles, benzoxazoles, naphthoxazoles, anthroxazoles,phenanthroxazoles, isoxazoles, 1 ,2-thiazoles, 1 ,3-thiazoles, benzothiazoles, pyridazines, benzopyridazines, pyrimidines, benzopyrimidines, quinoxalines, 1 ,5-diazaanthracenes, 2,7-diazapyrenes,2.3-diazapyrenes, 1 ,6-diazapyrenes, 1 ,8-diazapyrenes, 4,5-diaza- pyrenes, 4,5,9, 10-tetraazaperylenes, pyrazines, phenazines, phenoxazines, phenothiazines, fluorubins, naphthyridines, azacarbazoles, benzocarbolines, phenanthrolines, 1 ,2,3-triazoles, 1 ,2,4-triazoles, benzotriazoles, 1 ,2,3-oxadiazoles, 1 ,2,4-oxadiazoles, 1 ,2,5-oxa- diazoles, 1 ,3,4-oxadiazoles, 1 ,2,3-thiadiazoles, 1 ,2,4-thiadiazoles,1 .2.5-thiadiazoles, 1 ,3,4-thiadiazoles, 1 ,3,5-triazines, 1 ,2,4-triazines,1 .2.3-triazines, tetrazoles, 1 ,2,4,5-tetrazines, 1 ,2,3,4-tetrazines,1 .2.3.5-tetrazines, purines, pteridines, indolizines and benzothiadiazoles, and combinations of these groups, which may be substituted by one or more radicals RR, where RRhas the same definition as in claim 15.

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