Process for preparing substituted pentacenes
The invention relates to a process of preparing substituted pentacenes, to novel pentacenes prepared by this process, to the use of the novel pentacenes as semiconductors or charge transport materials in optical, electrooptical or electronic devices including field effect transistors (FETs), electroluminescent, photovoltaic and sensor devices, and to FETs and other semiconducting components or materials comprising the novel pentacenes.
1. A compound of formula Ia:
wherein
R 1-4 are identical or different groups selected from straight chain or branched C 1-12 alkyl, fluoroalkyl or alkoxy, or F, Cl or cyano,
R 5-7 are identical or different carbyl or hydrocarbyl groups.
2. A formulation comprising one or more compounds of claim 1 and one or more solvents.
3. A formulation comprising one or more compounds of claim 1 and one or more organic binders, or precursors thereof, and optionally one or more solvents.
4. A charge transport, semiconducting, electrically conducting, photoconducting or light emitting material or component comprising one or more compounds according to claim 1 .
5. An optical, electrooptical, electronic, electroluminescent or photoluminescent component or device comprising one or more compounds according to claim 1 .
6. A component or device according to claim 5 , which is selected from the group consisting of electrooptical displays, LCDs, optical films, retarders, compensators, polarisers, beam splitters, reflective films, alignment layers, colour filters, holographic elements, hot stamping foils, coloured images, decorative or security markings, LC pigments, adhesives, non-linear optic (NLO) devices, optical information storage devices, electronic devices, organic semiconductors, organic field effect transistors (OFET), integrated circuits (IC), thin film transistors (TFT), Radio Frequency Identification (RFID) tags, organic light emitting diodes (OLED), organic light emitting transistors (OLET), electroluminescent displays, organic photovoltaic (OPV) devices, organic solar cells (O-SC), organic laser diodes (O-laser), organic integrated circuits (O-IC), lighting devices, sensor devices, electrode materials, photoconductors, photodetectors, electrophotographic recording devices, capacitors, charge injection layers, Schottky diodes, planarising layers, antistatic films, conducting substrates, conducting patterns, photoconductors, electrophotographic applications, electrophotographic recording, organic memory devices, biosensors, and biochips.
7. A compound according to claim 1 , wherein the carbyl or hydrocarbyl groups for R 5 -R 7 are independently selected from: a C 1 -C 40 alkyl group, a C 2 -C 40 alkenyl group, a C 2 -C 40 alkynyl group, a C 3 -C 40 allyl group, a C 4 -C 40 alkyldienyl group, a C 4 -C 40 polyenyl group, a C 6 -C 18 aryl group, a C 6 -C 40 alkylaryl group, a C 6 -C 40 arylalkyl group, a C 4 -C 40 cycloalkyl group or a C 4 -C 40 cycloalkenyl group.
8. A compound according to claim 1 , wherein the carbyl or hydrocarbyl groups for R 5 -R 7 are independently selected from:
a mono-, bi- or tricyclic aromatic or heteroaromatic group with up to 25 C-atoms that may also comprise condensed rings and is optionally substituted with one or more groups L, wherein L is F, Cl, Br, I or an alkyl, alkoxy, alkylcarbonyl or alkoxycarbonyl group with 1 to 12 C-atoms, wherein one or more H atoms may optionally be replaced by F or Cl, or
a straight chain, branched or cyclic alkyl with 1 to 20 C-atoms, which is unsubstituted or mono- or polysubstituted by F, Cl, Br or I, and wherein one or more non-adjacent CH 2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR 0 —, —SiR 0 R 00 —, —CY 1 ═CY 2 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another, wherein:
R 0 and R 00 are independently of each other H or alkyl with 1 to 12 C-atoms, and
Y 1 and Y 2 are independently of each other H, F, Cl or CN.
9. A compound according to claim 1 , wherein the carbyl or hydrocarbyl groups for R 5-7 are identical optionally substituted alkyl groups.
10. A compound according to claim 9 , wherein R 1-4 are identical straight chain C 1-12 alkyl groups.
11. A compound according to claim 1 , wherein R 1-4 are identical straight chain C 1-12 alkyl groups.
12. A compound of formula Ia:
wherein
R 1-4 are identical or different groups selected from straight chain or branched C 1-12 alkyl, fluoroalkyl or alkoxy, or F, Cl or cyano,
R 5-7 are identical or different carbyl or hydrocarbyl groups,
which is obtained by a process comprising the following steps:
a1) reducing a 4,7-disubstituted isobenzofuran-1,3-dione (2) in the presence of a reducing agent to form the 4,7-disubstituted 3H-isobenzofuran-1-one (4),
or
a2) oxidizing a 1,2-bis(hydroxymethyl)-3,6-disubstituted benzene (3) in the presence of an oxidizing agent to form a 4,7-disubstituted 3H-isobenzofuran-1-one (4),
or
a3) oxidizing a 1,2-bis(hydroxymethyl)-3,6-disubstituted benzene (3) in the presence of an oxidizing agent to form a 4,7-disubstituted 1-hydroxy-1,3-dihydro-isobenzofuran (5a),
and, in case of step a1) or step a2),
b) reducing the product (4) of step a1) or a2) in the presence of a reducing agent to form a 4,7-disubstituted 1-hydroxy-1,3-dihydro-isobenzofuran (5a),
and
c) methylating the product (5a) of step a3) or b) to form a 4,7-disubstituted 1-methoxy-1,3-dihydro-isobenzofuran (5b),
d) eliminating the product (5b) of step c) in the presence of a base to form a 4,7-disubstituted isobenzofuran (6),
e) reacting the product (6) of step d) with p-benzoquinone by Diels-Alder cycloaddition to form a bis-cycloadduct (7),
f) dehydrating the product (7) of step e) in the presence of a base to form a 1,4,8,11-tetrasubstituted 6,13-pentacenequinone (8), and
g) alkynating the product (8) of step f) with a monosubstituted metal acetylide to form a 1,4,8,11-tetrasubstituted 6,13-bis(1-substituted ethynyl) pentacene (9).