Systems and methods for production of artificial eumelanin

Abstract

“Black” photoactive materials that comprise synthetic eumelanin polymers are provided, as are methods of making and using the polymers. The synthetic eumelanin polymers are made from the plant oil vanillin, and exhibit defined structural and chemical characteristics (e.g. homogeneity, solubility, etc.) that make them suitable for use in devices that require photoactive materials, such as solar cells.

1 . An indole as depicted in Formula I: 
       
         
           
           
               
               
           
         
       
       where
 R1, R2, R3 and R4 vary independently and may be the same or different, and can be H, substituted or unsubstituted alkyl, substituted or unsubstituted alkylester, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy moiety, substituted or unsubstituted polyethylene glycol (PEG), a macroinitator, a polymer or a crosslinker; 
 A1 and A2 may be the same or different and are halogen, R 3 Sn, B(OR) 2 , OTf, SiR 3 , or Si(OR) 3 ; and 
 P is H or a protecting moiety. 
 
     
     
         2 . The indole of  claim 1 , wherein said protecting moiety is C1 to C20 branched or unbranched, substituted or unsubstituted alkyl; PEG, a carbamate, an acetamide, benzyl, or tosylamide. 
     
     
         3 . The indole of  claim 1 , wherein said indole is methyl 4,7-dibromo-5,6-dimethoxy-N-methyl-1H-indole-2-carboxylate (DBI) as depicted in Formula II 
       
         
           
           
               
               
           
         
       
     
     
         4 . A method of making methyl 4,7-dibromo-5,6-dimethoxy-N-methyl-1H-indole-2-carboxylate (DBI), comprising
 reacting vanillin   
       
         
           
           
               
               
           
         
       
       to form DBI 
       
         
           
           
               
               
           
         
       
     
     
         5 . A method of  claim 4 , wherein said step of reacting comprising the steps of:
 i) methylating vanillin   
       
         
           
           
               
               
           
         
       
       to yield compound 2, 
       
         
           
           
               
               
           
         
         ii) nitrating said compound 2 to yield compound 3 
       
       
         
           
           
               
               
           
         
         iii) brominating said compound 3 to yield compound 4; 
       
       
         
           
           
               
               
           
         
         iv) reacting said compound 4 using methyl bromoacetate in aqueous sodium bicarbonate to yield compound 5; 
       
       
         
           
           
               
               
           
         
         v) reacting said compound 5 by microwave-assisted or conventional Cadogan synthesis to yield compound 6; 
       
       
         
           
           
               
               
           
         
         vi) N-methylation of the compound 6 to yield compound 7, 4,7-dibromo-5,6-dimethoxy-N-methyl-1H-indole-2-carboxylate (DBI) 
       
       
         
           
           
               
               
           
         
       
     
     
         6 . A polymer of Formula III 
       
         
           
           
               
               
           
         
       
       where R1, R2, R3 and R4 vary independently and may be the same or different, and can be H; substituted or unsubstituted alkyl; substituted or unsubstituted alkylester; substituted or unsubstituted alkoxy; substituted or unsubstituted aryloxy; substituted or unsubstituted polyethylene glycol (PEG); a macroinitator; a polymer or a crosslinker;
 P is H or a protecting moiety; 
 UCP is present or absent and if present is an unsaturated carbon pair which is connected directly to a repeat unit of the polymer or is connected indirectly to a repeat unit of the polymer through a substituted or unsubstituted aromatic; and 
 n ranges from about 10 to about 1000. 
 
     
     
         7 . The polymer of  claim 6 , wherein said protecting moiety is methyl, ethyl, PEG, a carbamate, an acetamides, benzyl, or tosylamide. 
     
     
         8 . The polymer of  claim 6 , wherein one or more of R1-R4 is crosslinked to a second polymer of Formula III. 
     
     
         9 . The polymer of  claim 6 , wherein UCP is present and said polymer has a formula 
       
         
           
           
               
               
           
         
       
     
     
         10 . The polymer of  claim 9 , wherein said UCP is a triple bond which is connected directly to said repeat unit of the polymer and the polymer is 
       
         
           
           
               
               
           
         
       
     
     
         11 . The polymer of  claim 9 , wherein said UCP is connected indirectly to said repeat unit of the polymer and the polymer is 
       
         
           
           
               
               
           
         
       
       where Y1, Y2, Y3 and Y4 are the same or different and are selected from
 i) H or a saturated or unsaturated, branched or unbranched, substituted or unsubstituted alkyl with from about 1 to about 30 carbon atoms; or 
 ii) OR where R is H or a saturated or unsaturated, branched or unbranched, substituted or unsubstituted alkyl with from about 1 to about 30 carbon atoms. 
 
     
     
         12 . The polymer of  claim 11 , wherein said UCP is a double bond, Y1 and Y 4 are H and Y2 and Y3 are RO, where R is dodecyl. 
     
     
         13 . The polymer of  claim 11 , wherein said UCP is a triple bond, Y1 and Y 4 are H and Y2 and Y3 are RO, where R is dodecyl or 2-ethylhexyl. 
     
     
         14 . A method of forming a polymer comprising the step of reacting 4,7-dibromo-5,6-dimethoxy-N-methyl-1H-indole-2-carboxylate (DBI) 
       
         
           
           
               
               
           
         
       
       with a compound of formula X1-UCP-X2, wherein
 UCP is an unsaturated carbon pair and 
 X1 and X2 are the same or different and are chemical groups capable of displacing Br and forming a covalent bond at positions 4 and 7 of said DBI. 
 
     
     
         15 . The method of  claim 14 , wherein X1 and X2 are Bu 3 Sn. 
     
     
         16 . A method of forming a polymer comprising the step of reacting 4,7-dibromo-5,6-dimethoxy-N-methyl-1H-indole-2-carboxylate (DBI) 
       
         
           
           
               
               
           
         
       
       with a compound of formula 
       
         
           
           
               
               
           
         
       
       wherein UCP is an unsaturated carbon pair 
       and wherein Y1, Y2, Y3 and Y4 are the same or different and are selected from
 i) H or a saturated or unsaturated, branched or unbranched, substituted or unsubstituted alkyl with from about 1 to about 30 carbon atoms; or 
 ii) OR where R is H or a saturated or unsaturated, branched or unbranched, substituted or unsubstituted alkyl with from about 1 to about 30 carbon atoms. 
 
     
     
         17 . The method of  claim 16 , wherein said UCP is a double bond, Y1 and Y 4 are H and Y2 and Y3 are RO, where R is dodecyl. 
     
     
         18 . The method of  claim 16 , wherein said UCP is a triple bond, Y1 and Y 4 are H and Y2 and Y3 are RO, where R is dodecyl or 2-ethylhexyl. 
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . A solution comprising
 a plurality of polymers of  claim 6  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         29 . The solution of  claim 28 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         30 . A solution comprising
 a plurality of polymers of  claim 7  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         31 . The solution of  claim 30 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         32 . A solution comprising
 a plurality of polymers of  claim 8  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         33 . The solution of  claim 32 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         34 . A solution comprising
 a plurality of polymers of  claim 9  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         35 . The solution of  claim 34 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         36 . A solution comprising
 a plurality of polymers of  claim 10  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         37 . The solution of  claim 36 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         38 . A solution comprising
 a plurality of polymers of  claim 11  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         39 . The solution of  claim 38 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         40 . A solution comprising
 a plurality of polymers of  claim 12  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         41 . The solution of  claim 40 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         42 . A solution comprising
 a plurality of polymers of  claim 13  and/or a plurality of unpolymerized or partially polymerized repeat units thereof; and   a solvent.   
     
     
         43 . The solution of  claim 42 , wherein said solvent is selected from the group consisting of: dichloromethane, (DCM), tetrahydrofuran (THF), chloroform (CHCl 3 ), toluene, xylene, dimethylformamide (DMF), chlorobenzene, o-dichlorobenzene, and trichlorobenzene, dimethylsulfoxide (DMSO), methanol (MeOH) and ethanol (EtOH) and water. 
     
     
         44 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 6 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         45 . The method of  claim 44  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         46 . A polymer thin film formed by the method of  claim 44 . 
     
     
         47 . A device comprising a polymer thin film of  claim 46 . 
     
     
         48 . The device of  claim 47 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         49 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 7 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         50 . The method of  claim 49  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         51 . A polymer thin film formed by the method of  claim 49 . 
     
     
         52 . A device comprising a polymer thin film of  claim 51 . 
     
     
         53 . The device of  claim 52 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         54 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 8  and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         55 . The method of  claim 54  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         56 . A polymer thin film formed by the method of  claim 54 . 
     
     
         57 . A device comprising a polymer thin film of  claim 56 . 
     
     
         58 . The device of  claim 57 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         59 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 9 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         60 . The method of  claim 59  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         61 . A polymer thin film formed by the method of  claim 59 . 
     
     
         62 . A device comprising a polymer thin film of  claim 60 . 
     
     
         63 . The device of  claim 62 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         64 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 10 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         65 . The method of  claim 64  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         66 . A polymer thin film formed by the method of  claim 64 . 
     
     
         67 . A device comprising a polymer thin film of  claim 66 . 
     
     
         68 . The device of  claim 67 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         69 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 11  and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         70 . The method of  claim 69  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         71 . A polymer thin film formed by the method of  claim 69 . 
     
     
         72 . A device comprising a polymer thin film of  claim 70 . 
     
     
         73 . The device of  claim 72 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         74 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 12 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         75 . The method of  claim 74  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         76 . A polymer thin film formed by the method of  claim 74 . 
     
     
         77 . A device comprising a polymer thin film of  claim 75 . 
     
     
         78 . The device of  claim 77 , wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen. 
     
     
         79 . A method of making a photoactive semi-conducive material comprising
 i) applying to a substrate, a solution comprising
 a plurality of polymers of  claim 13 , and/or a plurality of unpolymerized and/or partially polymerized repeat units thereof; and 
 a solvent; 
   
       and
 ii) allowing said solvent to evaporate from said substrate, thereby forming a photoactive semi-conducive material on said substrate. 
 
     
     
         80 . The method of  claim 79  wherein said photoactive semi-conducive material is a polymer thin film. 
     
     
         81 . A polymer thin film formed by the method of  claim 79 . 
     
     
         82 . A device comprising a polymer thin film of  claim 80 . 
     
     
         83 . The device of  claim 82  wherein said device is selected from the group consisting of: a solar cell, a transistor, a fuel cell, a lighting device, and a display screen.