Water-soluble distyrylbenzene chromophores for applications in optoelectronic technologies
View Patent ↗Two-photon or multi-photon chromophores having a conjugated pi-electron system with donating groups at each end of the pi-electron system providing charge-transfer properties, and having quaternary amine groups that can enhance the solubility of the chromophore in water. In a particular embodiment, the chromophore is based on a distyrylbenzene core, with donor or acceptor groups attached to the central benzene ring.
1. A chromophore having the following structural formula (I):
wherein Ar 1 , Ar 2 and Ar 3 are each independently a substituted or non-substituted aromatic hydrocarbon or aromatic heterocyclic ring; Ak 1 , Ak 2 , Ak 3 and Ak 4 are each independently a substituted or non-substituted alkyl or alkylene group; R 1 , R 2 and R 3 are each independently a substituted or non-substituted alkyl group; and X 1 is a counter anion.
2. The chromophore of claim 1 wherein Ar 1 , Ar 2 and Ar 3 are single aromatic rings.
3. The chromophore of claim 2 wherein Ar 1 , Ar 2 and Ar 3 are benzene rings.
4. The chromophore of claim 1 wherein Ar 2 includes a donor or acceptor group.
5. The chromophore of claim 1 wherein Ak 1 , Ak 2 , Ak 3 and Ak 4 are each (CH 2 ) n , where n is from 1 to 10, and R 1 , R 2 and R 3 are each (CH 2 ) m —H, where m is from 1 to 10.
6. A distyrylbenzene chromophore having the following structural formula (II):
wherein A 1 and A 2 are each independently a hydrogen, or a donor or acceptor group; and R is [(CH 2 ) n ] 6 —NR′ 3 X, where R′ is (CH 2 ) m —H, X is any anion, n is from 1 to 10 and m is from 1 to 10.
7. The chromophore of claim 6 in which the donor group is selected from the group consisting of I, Br, Cl, OC(O)R″, SH, OH, SR″, OR″, NHC(O)R″, NH 2 , NH″R, S − , and O − , where R″ refers to an alkyl group containing 1–50 carbon atoms.
8. The chromophore of claim 6 in which the acceptor group is selected from the group consisting of F, C(O)NR″ 2 , C(O)NHR″, C(O)NH 2 , C(O)OR″, C(O)OH, C(O)R″, C(O)H, CN, S(O 2 )R″, and NO 2 , and where R″ refers to an alkyl group containing 1–50 carbon atoms.
9. The chromophore of claim 6 in which A 1 and A 2 are each hydrogen and n=1.
10. A distyrylbenzene chromophore having the following structural formula (III):
wherein R is (CH 2 ) 6 —NR′ 3 X, R′ is CH 3 , and X is any anion.
11. A distyrylbenzene chromophore having the following structural formula (IV):
wherein R is (CH 2 ) 6 —NR′ 3 X, R′ is CH 3 and X is any anion.
12. A method of preparing a distyrylbenzene chromophore, comprising reacting a 1,4-dibenzylphosphonate with a haloalkylamino-benzaldehyde and adding a trialkylamine by condensation to said distyrylbenzene chromophore whereby to provide water solubility to said chromophore.
13. The method of claim 12 in which said haloalkylamino-benzaldehyde is a N,N-bis-(6-iodoalkyl)-4-amino-benzaldehyde where the alkyl group has from 1 to 10 carbon atoms.
14. The method of claim 13 in which said N,N-bis-(6-iodohexyl)-4-amino-benzaldehyde is prepared by reacting N,N-bis-(6-hydroxyhexyl)-benzaldehyde with phosphorous oxychloride.
15. The method of claim 14 in which said N,N-bis-(6-hydroxyhexyl)-benzaldehyde is prepared by reacting aniline and 6-chloro-1-hexanol with a carbonate.
16. A method of preparing a water-soluble two-photon absorbing distyrylbenzene chromophore, comprising the following steps:
a) reacting analine 6-chloro-1-hexanol and potassium carbonate to yield N,N-Bis-(6-hydroxyhexyl)-aniline of the formula:
b) reacting N,N-Bis-(6-hydroxyhexyl)-aniline and phosphorous oxychloride to yield N,N-Bis-(6-chlorohexyl)-4-amino)-benzaldehyde of the formula:
c) reacting N,N-Bis-(6-chlorohexyl)-4-amino)-benzaldehyde and sodium iodide to yield N,N-Bis-(6-iodohexyl)-4-amino-benzaldehyde of the formula:
d) reacting N,N-Bis-(6-iodohexyl)-4-amino-benzaldehyde and 1,4-dibenzylphosphonate of the formula
to yield a precursor chromophore of the formula:
e) reacting the precursor chromophore with trimethylamine to yield a distyrylbenzene chromophore of the formula: