Photo-crosslinkable emissive molecular materials
For applications in the fields of organic electronics and photonics, disclosed are fluorescent charge-transfer compounds emitting in the visible spectral range from blue to red, including a triarylamine moiety, an electron-withdrawing group and at least two photopolymerizable groups. Also disclosed is a method for manufacturing a film-forming and photo-crosslinkable composition including at least one compound of the invention and its use as a precursor of a photocrosslinked emissive layer.
1. A photopolymerizable emissive compound of general formula (I):
wherein X and Y each independently represent an aryl or heteroaryl;
A and B each independently represent a chiral center;
L 1 and L 2 each independently represent an alkyl group comprising 1 to 10 carbon atoms, linear or branched, that may be interrupted by one or several atoms —O—, —N— or —S—; said group being optionally substituted with at least one alkyl, alkene, alkyne, oxo, amine, amide, cyano, hydroxyl, carboxy group;
T 1 and T 2 each independently represent a photopolymerizable group selected from at least one acryloyl, alkylacryloyl, oxetane, alkyloxetane, styryl, allyl, acrylamide, methacrylamide or cinnamate;
Z represents an electron-withdrawing group.
2. A photo-crosslinkable emissive compound of general formula (II-a), (II-b), (II-c) or (II-d) according to claim 1 :
3. An intermediate compound of general formula:
wherein X and Y each independently represent an aryl or heteroaryl;
R represents a —OH or —OTBDMS group;
A and Beach independently represent a chiral center; and
Z represents an electron-withdrawing group.
4. A composition comprising at least one compound according to claim 1 , an initiator and an organic solvent.
5. A kit comprising a first compartment comprising at least one compound according to claim 1 , and an organic solvent, and a second compartment comprising the photoinitiator.
6. A method for manufacturing a compound according to claim 1 , comprising:
(i) synthesizing an intermediate compound of general formula (III-2) comprising an aldehyde group:
wherein A, B, X and Y are defined as in claim 1 ,
obtained by the reaction of the 4-di(4-bromophenyl)aminobenzaldehyde with the compound of formula (III-1):
also noted as
wherein A represents a chiral center; and X represents an aryl or heteroaryl;
(ii) a deprotection reaction;
(iii) in the case where Z of the compound according to claim 1 is not an aldehyde group, modifying the aldehyde group of the intermediate compound (III-2) into another electron-withdrawing group Z allowing the provision of intermediate compound of formula (III-3bis):
wherein A, B, X and Y are defined as in claim 1 , and Z represents an electron-withdrawing group;
(iv) and, modifying the compound obtained in (ii) in the case where Z of the compound according to claim 1 is an aldehyde group, or in (iii) in the case where Z of the compound according to claim 1 is not an aldehyde group, allowing for the introduction of spacers L comprising at least one photopolymerizable group T.
7. A method for manufacturing a substrate coated with a thin, amorphous, emissive, photo-crosslinkable and non-doped small molecule-based film, comprising the following steps:
a) providing a composition comprising at least one compound of general formula according to claim 1 , a solvent and a photoinitiator;
b) depositing the composition obtained in a) onto a substrate.
8. A method for manufacturing a photo-crosslinked emissive organic layer or a photo-crosslinked emissive multilayer system comprising the following steps:
a′) implementing the method of manufacturing a substrate coated with a photo-crosslinkable emissive film according to claim 7 ; then b′) the photopolymerization of said film;
c′) optionally, repeating steps a′) and b′) resulting in an insoluble emissive multilayer device.
9. A composition comprising at least one compound according to claim 2 , an initiator and an organic solvent.
10. A kit comprising a first compartment comprising at least one compound according to claim 2 , and an organic solvent, and a second compartment comprising the photoinitiator.
11. A method for manufacturing a substrate coated with a thin, amorphous, emissive, photo-crosslinkable and non-doped small molecule-based film, comprising the following steps:
a) providing a composition comprising at least one compound of general formula according to claim 2 , a solvent and a photoinitiator;
b)depositing the composition obtained in a) onto a substrate.
12. The photopolymerizable emissive compound of general formula (I) according to claim 1 , wherein X and Y each independently represent a phenyl group.
13. The photopolymerizable emissive compound of general formula (I) according to claim 1 , wherein A and Beach independently represent a —CHMe— group.
14. The photopolymerizable emissive compound of general formula (I) according to claim 1 , wherein L 1 and L 2 each independently represent an alkyl group comprising 3 to 10 carbon atoms, linear or branched, that may be interrupted by one or several atoms —O—, —N— or —S—; said group being optionally substituted with at least one alkyl, alkene, alkyne, oxo, amine, amide, cyano, hydroxyl, carboxy group.
15. The photopolymerizable emissive compound of general formula (I) according to claim 1 , wherein T 1 and T 2 simultaneously represent an acryloyl group or an alkyloxetane group.
16. The photopolymerizable emissive compound of general formula (I) according to claim 1 , wherein Z represents an aldehyde, dicyanovinylidene, cyanovinylidene, benzothiadiazole group or an alkyl ester group comprising at least one photopolymerizable group selected from at least one acryloyl, alkylacryloyl, oxetane, alkyloxetane, styryl, allyl, acrylamide, methacrylamide or cinnamate.
17. The intermediate compound according to claim 3 , wherein X and Y each independently represent a phenyl group.
18. The intermediate compound according to claim 3 , wherein A and B each independently represent a —CHMe— group.
19. The intermediate compound according to claim 3 , wherein Z represents an aldehyde, dicyanovinylidene, cyanovinylidene, benzothiadiazole group or an alkyl ester group comprising at least one photopolymerizable group selected from at least one acryloyl, alkylacryloyl, oxetane, alkyloxetane, styryl, allyl, acrylamide, methacrylamide or cinnamate.