Diketopyrrolopyrrole polymers as organic semiconductors

Abstract

The present invention relates to polymers comprising a repeating unit of the formula (I) and their use as organic semiconductor in organic devices, especially a diode, an organic field effect transistor and/or a solar cell, or a device containing a diode and/or an organic field effect transistor, and/or a solar cell. The polymers according to the invention have excellent solubility in organic solvents and excellent film-forming properties. In addition, high efficiency of energy conversion, excellent field-effect mobility, good on/off current ratios and/or excellent stability can be observed, when the polymers according to the invention are used in semiconductor devices or organic photovoltaic (PV) devices (solar cells).

1 . A polymer comprising repeating unit(s) of the formula 
       
         
           
           
               
               
           
         
       
       wherein
 a, b, c, d, e and f are 0 to 200; 
 Ar 1  and Ar 1′  are independently of each other a group of formula 
 
       
         
           
           
               
               
           
         
         Ar 2 , Ar 2′ , Ar 3 , Ar 3′ , Ar 4  and Ar 4′  are independently of each other a group of formula 
       
       
         
           
           
               
               
           
         
         p is 0, 1, 2, 3 or 4, if possible, 
         R 1  and R 2  may be the same or different and are selected from hydrogen, a C 1 -C 25 alkyl group, an alkenyl group, an alkynyl group, which may optionally be substituted by E and/or interrupted by D, an allyl group, which can be substituted one to three times with C 1 -C 4 alkyl; a cycloalkyl group, which can be substituted one to three times with C 1 -C 8 alkyl, C 1 -C 8 thioalkoxy, or C 1 -C 8 alkoxy, or a cycloalkyl group, which can be condensed one or two times by phenyl, which can be substituted one to three times with C 1 -C 4 -alkyl, halogen, nitro or cyano; a cycloalkenyl group, a ketone or aldehyde group, an ester group, a carbamoyl group, a silyl group, a siloxanyl group, Ar 10  or —CR 5 R 6 —(CH 2 ) 9 —Ar 10 , wherein 
         R 5  and R 6  independently from each other are hydrogen, fluorine, cyano or C 1 -C 4 alkyl, which can be substituted by fluorine, chlorine or bromine, or phenyl, which can be substituted one to three times with C 1 -C 4 alkyl, 
         Ar 10  is aryl or heteroaryl, which may optionally be substituted by G, in particular phenyl or 1- or 2-naphthyl which can be substituted one to three times with C 1 -C 8 alkyl, C 1 -C 8 thioalkoxy, and/or C 1 -C 8 alkoxy, and g is 0, 1, 2, 3 or 4, 
         R 3  may be the same or different within one group and is selected from C 1 -C 25 alkyl, which may optionally be substituted by E and/or interrupted by D, C 6 -C 24 aryl, which may optionally be substituted by G, C 2 -C 20 heteroaryl, which may optionally be substituted by G, C 1 -C 18 alkoxy, which may optionally be substituted by E and/or interrupted by D, C 7 -C 25 aralkyl, wherein ar (=aryl) of aralkyl may optionally be substituted by G, or —CO—R 28 , or two or more groups R 3  which are adjacent to each other, form a ring; 
         R 4 , R 4′ , R 7  and R 7′  independently from each other are hydrogen, C 1 -C 25 alkyl, which may optionally be substituted by E and/or interrupted by D, C 6 -C 24 aryl, which may optionally be substituted by G, C 2 -C 20 heteroaryl, which may optionally be substituted by G, C 1 -C 18 alkoxy, which may optionally be substituted by E and/or interrupted by D, C 7 -C 25 aralkyl, wherein ar (=aryl) of aralkyl may optionally be substituted by G, or —CO—R 28 ; or R 4 and R 4′  form a ring; 
         D is —CO—; —COO—; —S—; —SO—; —SO 2 —; —O—; —NR 25 —; —CR 23 ═CR 24 —; or —C—C—; and 
         E is —OR 29 ; —SR 29 ; —NR 25 R 26 ; —COR 28 ; —COOR 27 ; —CONR 25 R 26 ; —CN; or halogen; G is E, C 1 -C 18 alkyl, which may be interrupted by D, or C 1 -C 18 alkoxy which is substituted by E and/or interrupted by D, wherein 
         R 23 , R 24 , R 25  and R 26  are independently of each other H; C 6 -C 18 aryl; C 6 -C 18 aryl which is substituted by C 1 -C 18 alkyl, or C 1 -C 18 alkoxy; C 1 -C 18 alkyl; or C 1 -C 18 alkyl which is interrupted by —O—; 
         R 27  and R 28  are independently of each other H; C 6 -C 18 aryl; C 6 -C 18 aryl which is substituted by C 1 -C 18 alkyl, or C 1 -C 18 alkoxy; C 1 -C 18 alkyl; or C 1 -C 18 alkyl which is interrupted by —O—, 
         R 29  is H; C 6 -C 18 aryl; C 6 -C 18 aryl, which is substituted by C 1 -C 18 alkyl, or C 1 -C 18 alkoxy; C 1 -C 18 alkyl; or C 1 -C 18 alkyl which is interrupted by —O—, 
         R 109  and R 110  are independently of each other H, C 1 -C 18 alkyl, C 1 -C 18 alkyl which is substituted by E and/or interrupted by D, C 6 -C 24 aryl, C 6 -C 24 aryl which is substituted by G, C 2- C 20 heteroaryl, C 2 -C 20 heteroaryl which is substituted by G, C 2 -C 18 alkenyl, C 2 -C 18 alkynyl, C 1 -C 18 alkoxy, C 1 -C 18 alkoxy which is substituted by E and/or interrupted by D, or C 7 -C 25 aralkyl, or 
         R 109  and R 110  together form a group of formula ═CR 100 R 101 , wherein 
         R 100  and R 101  are independently of each other H, C 1 -C 18 alkyl, C 1 -C 18 alkyl which is substituted by E and/or interrupted by D, C 6 -C 24 aryl, C 6 -C 24 aryl which is substituted by G, or C 2 -C 20 heteroaryl, or C 2 -C 20 heteroaryl which is substituted by G, or 
         R 109  and R 110  together form a five or six membered ring, which optionally can be substituted by C 1 -C 18 alkyl, C 1 -C 18 alkyl which is substituted by E and/or interrupted by D, C 6 -C 24 aryl, C 6 -C 24 aryl which is substituted by G, C 2 -C 20 heteroaryl, C 2 -C 20 heteroaryl which is substituted by G, C 2 -C 18 alkenyl, C 2 -C 18 alkynyl, C 1 -C 18 alkoxy, C 1 -C 18 alkoxy which is substituted by E and/or interrupted by D, C 7 -C 25 aralkyl, or —C(═O)—R 18 , 
         R 111  is H, a C 1 -C 25 alkyl group, a C 4 -C 18 cycloalkyl group, a C 1 -C 25 alkoxy group, in which one or more carbon atoms which are not adjacent to each other could be replaced by —O—, —S—, or —C(═O)—O—, and/or wherein one or more hydrogen atoms can be replaced by F, a C 6 -C 24 aryl group, or a C 6 -C 24 aryloxy group, wherein one or more carbon atoms can be replaced by O, S, or N, and/or which can be substituted by one or more non-aromatic groups R 111 ; 
         m can be the same or different at each occurrence and is 0, 1, 2, or 3; 
         X 1  is a hydrogen atom, or a cyano group, 
         with the proviso that, if Ar 1  and Ar 1′  are a group of formula 
       
       
         
           
           
               
               
           
         
       
       and a and d are both 1 and Ar 2  and Ar 2′  are different from a group of formula 
       
         
           
           
               
               
           
         
       
       with the proviso that, if Ar 1  and Ar 1′  are a group of formula 
       
         
           
           
               
               
           
         
       
       a and d are not 0; and
 with the proviso, that a polymer of the formula 
 
       
         
           
           
               
               
           
         
       
       is excluded. 
     
     
         2 . The polymer according to  claim 1 , wherein R 1  and R 2  are independently from each other hydrogen, C 1 -C 25 alkyl, which can optionally be interrupted by one or more oxygen atoms, C 5 -C 12 -cycloalkyl which can be substituted one to three times with C 1 -C 8 alkyl and/or C 1 -C 8 alkoxy, or C 5 -C 12 cycloalkyl, which can be condensed one or two times by phenyl, which can be substituted one to three times with C 1 -C 4 alkyl, halogen, nitro or cyano, phenyl or 1- or 2-naphthyl which can be substituted one to three times with C 1 -C 8 alkyl and/or C 1 -C 8 alkoxy, or —CR 5 R 6 —(CH 2 ) g —Ar 10  wherein R 5  and R 6  are hydrogen, Ar 10  is for phenyl or 1- or 2-naphthyl, which can be substituted one to three times with C 1 -C 8 alkyl and/or C 1 -C 8 alkoxy, and g stands for 0 or 1. 
     
     
         3 . The polymer according to  claim 1 , wherein Ar 1  and Ar 1′  are the same and are a group of formula 
       
         
           
           
               
               
           
         
       
       and
 Ar 2 , Ar 2′ , Ar 3 , Ar 3′ , Ar 4  and Ar 4′  are independently of each other a group of formula 
 
       
         
           
           
               
               
           
         
       
       wherein
 p stands for 0, 1, or 2, R 3  may be the same or different within one group and is selected from C 1 -C 25 alkyl, which may optionally be substituted by E and/or interrupted by D, or C 1 -C 18 alkoxy, which may optionally be substituted by E and/or interrupted by D; 
 R 4  is C 6 -C 25 alkyl, which may optionally be substituted by E and/or interrupted by D, C 6 -C 14 aryl which may optionally be substituted by G, C 1 -C 25 alkoxy, which may optionally be substituted by E and/or interrupted by D, or C 7 -C 15 aralkyl, wherein ar may optionally be substituted by G, 
 D is —CO—, —COO—, —S—, —SO—, —SO 2 —, —O—, —NR 25 —, wherein R 25  is C 1 -C 12 alkyl; 
 E is —OR 29 ; —SR 29 ; —NR 25 R 25 ; —COR 28 ; —COOR 27 ; —CONR 25 R 25 ; or —CN; wherein R 25 , R 27 , R 28  and R 29  are independently of each other C 1 -C 12 alkyl or C 6 -C 14  aryl, 
 G has the same preferences as E, or is C 1 -C 18 alkyl. 
 
     
     
         4 . The polymer according to  claim 3 , wherein 
       
         
           
           
               
               
           
         
       
       may be different or are the same and are a group of formula 
       
         
           
           
               
               
           
         
       
       indicates the bond to the diketopyrrolopyrrole skeleton, and R 4  is as defined in  claim 3  and R 4′  has the meaning of R 4 . 
     
     
         5 . The polymer according to  claim 1 , wherein the polymer comprises repeating units of the formula 
       
         
           
           
               
               
           
         
       
       wherein a, b, c, d, e, f, R 1 , R 2 , Ar 1 , Ar 1′ , A 2 , A 2′ , Ar 3 , Ar 3′ , Ar 4  and Ar 4′  are as defined in  claim 1 , h is 1, and
 Ar 5  is a group of formula 
 
       
         
           
           
               
               
           
         
       
       wherein R 7  and R 7′  are as defined in  claim 1 ; or
 the polymer has the structure of formula 
 
       
         
           
           
               
               
           
         
       
       wherein the First Repeating Unit is a repeating unit of formula I according to  claim 1 ,
 the Branching Unit is a unit having more than two linkage sites, and 
 q and t are integers. 
 
     
     
         6 . The polymer according to  claim 1 , comprising repeating units of the formula 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
       wherein
 R 1  and R 2′  are independently from each other C 1 -C 25 alkyl, and 
 R 3  and R 3′  are independently from each other C 6 -C 25 alkyl, which may optionally be interrupted by one or more oxygen atoms, 
 R 4  and R 4′  are independently from each other C 6 -C 25 alkyl, which may optionally be interrupted by one or more oxygen atoms, and 
 R 7 and R 7′  are independently from each other C 6 -C 25 alkyl, which may optionally be interrupted by one or more oxygen atoms. 
 
     
     
         7 . A semiconductor device, comprising a polymer of the formula I according to  claim 1 . 
     
     
         8 . A process for the preparation of an organic semiconductor device, wherein said process comprises applying a solution and/or dispersion of a polymer of the formula I according to  claim 1  in an organic solvent to a suitable substrate and removing the solvent. 
     
     
         9 . A monomer of the formula 
       
         
           
           
               
               
           
         
       
       wherein
 B and C are independently of each other an optionally condensed aromatic, or heteroaromatic ring, 
 a, b, c, d, e, f, R 1 , R 2 , Ar 1 , Ar 1′ , Ar 2 , Ar 2′ , Ar 3 , Ar 3′ , Ar 4  and Ar 4′  are as defined in  claim 1  and X is ZnX 12 , —SnR 207 R 208 R 209 , wherein R 207 , R 208  and R 209  are identical or different and are H or C 1 -C 6 alkyl, wherein two radicals optionally form a common ring and these radicals are optionally branched or unbranched and X 12  is a halogen atom or —OS(O) 2 CF 3 , —OS(O) 2 -aryl, 
 
       
         
           
           
               
               
           
         
       
       —OS(O) 2 CH 3 , —B(OH) 2 , —B(OY 1 ) 2 , 
       
         
           
           
               
               
           
         
       
       BF 4 Na, or —BF 4 K, wherein Y 1  is independently in each occurrence a C 1 -C 10 alkyl group and Y 2  is independently in each occurrence a C 2 -C 10 alkylene group, such as —CY 3 Y 4 —CY 5 Y 6 —, or —CY 7 Y 8 —CY 9 Y 10 —CY 11 Y 12 —, wherein Y 3 , Y 4 , Y 5 , Y 6 , Y 7 , Y 8 , Y 9 , Y 10 , Y 11  and Y 12  are independently of each other hydrogen, a C 1 -C 10 alkyl group, —C(CH 3 ) 2 C(CH 3 ) 2 —, or —C(CH 3 ) 2 CH 2 C(CH 3 ) 2 —, with the proviso that, if Ar 1  and Ar 1′  are a group of formula 
       
         
           
           
               
               
           
         
       
       a and d are not 0 and Ar 2  and Ar 2′  are different from a group of formula 
       
         
           
           
               
               
           
         
       
       with the further proviso that, if Ar 1  and Ar 1′  are a group of formula 
       
         
           
           
               
               
           
         
       
       a and d are not 0. 
     
     
         10 . A method for the manufacture of a semiconductor device containing a semiconductor layer wherein said method comprises incorporating into said semiconductor layer an effective amount of the polymer of formula I according to  claim 1 . 
     
     
         11 . A polymer according to  claim 1  wherein a, b, c, d, e and f are 0, 1, 2, or 3. 
     
     
         12 . A polymer according to  claim 1  wherein m is 0, 1, or 2. 
     
     
         13 . A polymer according to  claim 12  wherein m is 0 or 1. 
     
     
         14 . The polymer according to  claim 3 , wherein R 4  is phenyl, naphthyl, or biphenylyl. 
     
     
         15 . The polymer according to  claim 3 , wherein R 25 , R 27 , R 28  and R 29  are independently of each other methyl, ethyl, n-propyl, iso-propyl, n-butyl, isobutyl, sec-butyl, hexyl, octyl, 2-ethyl-hexyl, phenyl, naphthyl, or biphenylyl. 
     
     
         16 . The polymer according to  claim 3 , wherein G is methyl, ethyl, n-propyl, iso-propyl, n-butyl, isobutyl, sec-butyl, hexyl, octyl, or 2-ethyl-hexyl. 
     
     
         17 . The semiconductor device according to  claim 7  wherein said semiconductor device is selected from the group consisting of diode, photodiode, organic field effect transistor, solar cell, and a device containing a diode and/or a photodiode and/or an organic field effect transistor, and/or a solar cell. 
     
     
         18 . The method according to  claim 10  wherein said semiconductor device or semiconductor layer is selected from the group consisting of charge-transport material, electrical conducting material, photoconducting material, light emitting material, surface-modifying material, electrode materials in batteries, alignment layers, organic field effect transistors, intergrated circuits, thin-film transistors, displays, RFITD tags, electroluminescent devices, photoluminescent devices, backlights of displays, photovoltaic devices, sensor devices, charge injection layers, Schottky diodes, memory devices, FeFET devices, planarising layers, antistatics, conductive substrates or patterns, photoconductors, and electrophotographic applications.