Aminated lignin-derived compounds and uses thereof

1. An aminated and/or sulfonated and/or otherwise substituted low molecular weight aromatic compound corresponding in structure to Formula (1)-(3):

wherein each R 1 -R 4 in Formula (1), each of R 1 -R 6 in Formula (2) and each of R 1 -R 8 in Formula (3)

is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; ester; halogen; optionally substituted amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl; cyanided and sulfonyl (—SO 3 H), and/or

wherein any two of adjacent substituents R 1 and R 2 and/or R 3 and R 4 of Formula (1) or any two of adjacent substituents of R 1 and R 2 and/or R 3 to R 6 of formula (2) or any two of adjacent substituents of R 1 -R 4 and/or R 5 -R 8 of formula (3) form at least one optionally substituted cyclic ring system,

provided that at least one of R 1 -R 4 in Formula (1), at least one of R 1 -R 6 in Formula (2) and/or at least one of R 1 -R 8 in Formula (3) is selected from optionally substituted amine.

2. The low molecular weight aromatic compound of claim 1 , wherein one, two or three of R 1 -R 4 in Formula (1), of R 1 -R 6 in Formula (2) and/or of R 1 -R 8 in Formula (3) is or are independently selected from optionally substituted amine; sulfonyl; and optionally substituted C 1-6 alkyl optionally comprising at least one heteroatom selected from N, O and S.

3. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (1)(a) or (b) and wherein R 1 and R 4 are each independently selected from —H; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine.

4. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (1)(a) or (b) and wherein:

R 1 is selected from —H; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 2 is selected from —H; —OH; C 1-6 alkoxy; and optionally substituted amine;

R 3 is selected from —H; —OH and C 1-6 alkoxy; and

R 4 is selected from —H; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S.

5. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (1)(a) or (b) and wherein:

(a) R 4 is selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S;

(b) R 4 is selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 3 is methoxy;

(c) R 4 is selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 2 and R 3 are methoxy;

(d) R 1 and R 4 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

(e) R 1 and R 4 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine; R 3 is methoxy;

(f) R 1 and R 4 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 2 and R 3 are methoxy; or

(g) R 2 and R 4 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 3 is methoxy,

wherein each of the other of R 1 -R 4 is OH or H.

6. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (2)(a) or (b) and wherein at least one of R 1 -R 6 is each independently selected from —H; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine.

7. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (3)(a) or (b) and wherein at least one of R 1 -R 8 is each independently selected from —H; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine.

8. The low molecular weight aromatic compound of claim 7 , wherein the compound corresponds in structure to Formula (3)(a) or (b), wherein:

(a) R 1 is optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; or optionally substituted amine;

(b) R 2 is optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; or optionally substituted amine;

R 1 , R 3 and R 4 are preferably OH;

(c) R 6 is optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; or optionally substituted amine;

R 1 and R 4 or R 1 , R 2 and R 4 are OH;

(d) R 2 and R 6 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine; R 1 and R 4 or R 1 , R 3 and R 4 are OH;

(e) R 3 and R 6 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

R 1 , R 2 and R 4 are preferably OH;

(f) R 2 and R 7 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine; or

(g) R 1 and R 4 are each independently selected from optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine;

wherein each of the other of R 1 -R 8 is C 1-6 alkoxy or H.

9. The low molecular weight aromatic compound of claim 1 , wherein the amine is selected from a primary, a secondary, a tertiary or a quaternary amine characterized by the formula —NH 2 , —NHR, -NG a 2 , -NG a 3 + , respectively, wherein each G a is independently selected from —H, -Alkyl, -Aryl, —SO 3 H, —SO 3 − , —PO 3 H 2 , —OH, -OAlkyl, —OOH, -OOAlkyl, —SH, -SAlkyl, —NH 2 , -NHAlkyl, -NAlkyl 2 , -NAlkyl 3 + , -NHG b , -NG b 2 , -NG b 3 + , —CHO, —COOH, -COOAlkyl, —CN, —CONH 2 , -CONHAlkyl, -CONAlkyl 2 , -Heteroaryl, -Heterocycyl, -NOG b , -N+OAlkyl, —F, —Cl—, and —Br;

wherein each G b is independently selected from —H, -Alkyl, -Aryl, —SO 3 H, —SO 3 − , —PO 3 H 2 , —OH, -OAlkyl, —OOH, -OOAlkyl, —SH, -SAlkyl, —NH 2 , -NHAlkyl, -NAlkyl 2 , -NAlkyl 3 + , —CHO, —COOH, -COOAlkyl, —CN, —CONH 2 , -CONHAlkyl, -CONAlkyl 2 , -Heteroaryl, -Heterocycyl, -N + OAlkyl, —F, —Cl—, and —Br.

10. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (1)(a) or (b) and wherein R 1 and R 4 are each independently or both selected from —H or —SO 3 H, R 2 is selected from —H, —OH, and C 1-6 alkoxy, or —SO 3 H, and R 3 is selected from —H, —OH and C 1-6 alkoxy.

11. The sulfonated low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (1)(a) or (b) and wherein:

(a) R 4 is SO 3 H;

(b) R 4 is SO 3 H, R 3 is methoxy;

(c) R 4 is SO 3 H, R 2 and R 3 are methoxy;

(d) R 1 and R 4 are SO 3 H;

(e) R 1 and R 4 are SO 3 H, R 3 is methoxy;

(f) R 1 and R 4 are SO 3 H, R 2 and R 3 are methoxy; or

(g) R 2 and R 4 are SO 3 H, and R 3 is methoxy,

wherein each of the other of R 1 -R 4 is OH or H.

12. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (2)(a) or (b),

wherein R 1 and R 2 are independently selected from —H, —OH and C 1-6 alkoxy, and R 3 -R 6 are independently selected from —H and —SO 3 H.

13. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to Formula (3)(a) or (b),

wherein R 1 , R 2 and R 4 are independently selected from —H, —OH and C 1-6 alkoxy, and R 3 , R 5 -R 8 are independently selected from —H and —SO 3 H.

14. The low molecular weight aromatic compound of claim 1 , wherein the compound is characterized by Formula (3)(a) or (b),

wherein:

(a) R 1 is SO 3 H;

(b) R 2 is SO 3 H; R 1 , R 3 and R 4 are OH;

(c) R 6 is SO 3 H; R 1 and R 4 or R 1 , R 2 and R 4 are OH;

(d) R 2 and R 6 are SO 3 H; R 1 and R 4 or R 1 , R 3 and R 4 are preferably OH;

(e) R 3 and R 6 are SO 3 H; R 1 , R 2 and R 4 are OH;

(f) R 2 and R 7 are SO 3 H; or

(g) R 1 and R 4 are SO 3 H;

wherein each of the other of R 1 -R 8 is/are C 1-6 alkoxy or H, preferably H.

15. A low molecular weight aromatic compound corresponding in structure to Formula (14)-(17):

wherein

each G 19 -G 508 of Formula (14)-(17) is independently selected from

—H, —R, -Alkyl, -Aryl, —SO 3 H, —SO 3 − , —PO 3 H 2 , —OH, —OR, —SH, —NH 2 , —NHR, -NG a 2 , —NG a 3 + , —CHO, —COOH, -COOG, —CN, —CONH 2 , —CONHR, -CONG a 2 , -Heteroaryl, -Heterocycyl, —NOR, —N + OR, —F, —Cl—, and —Br, or are joined together to form a saturated or unsaturated carbocycle;

wherein the Alkyl is selected from linear, branched or cyclic —C n H 2n-o and —C n H 2n-o-m G m ;

wherein the Aryl is selected from —C 6 H 5 , —C 10 H 7 , C 13 H 8 , C 14 H 9 , —C 6 H 5-m G m , —C 10 H 7-m G m , C 13 H 8-m G m , C 14 H 9-m G m ;

wherein the Heteroaryl is selected from —C 5-p N p H 5-p-q G q , —C 6-p N p H 5-p-q G q , —C 7-p N p H 7-p-q G q , —C 8-p N p H 6-p-q G q , —C 9-p N p H 7-p-q G q , —C 10-p N p H 7-p-q G q , C 4 OH 3-q G q , —C 6 OH 5-q G q , —C 7 OH 4-q G q , —C 6 O 2 H 3-q G q , —C 8 OH 5-q G q , —C 4 SH 3-q G q , —C 6 SH 5-q G q , —C 7 SH 4-q G q , —C 6 S 2 H 3-q G q , —C 8 SH 5-q G q , —C 3 ON p H 3-p-q G q , —C 6 ON p H 5-p-q G q , —C 7 ON p H 4-p-q G q , —C 6 O 2 N p H 3-p-q G q , —C 8 ON p H 5-p-q G q , —C 3 SN p H 3-p-q G q , —C 6 SN p H 5-p-q G q , —C 7 SN p H 4-p-q G q , —C 6 S 2 N p H 3-p-q G q , —C 6 OSN p H 3-p-q G q , —C 8 SN p H 5-p-q G q , —C 5-p N p + H 6-p-q G q , —C 6-p N p + H 6-p-q G q , —C 7-p N p + H 8-p-q G q , —C 8-p N p + H 7-p-q G q , —C 9-p N p + H 8-p-q G q , —C 10-p N p + H 8-p-q G q , —C 3 ON p + H 4-p-q G q , —C 6 ON p + H 6-p-q G q , —C 7 ON p + H 5-p-q G q , —C 6 S 2 N p + H 4-p-q G q , —C 6 OSN p + H 4-p-q G q , —C 8 SN p + H 6-p-q G q ,

C 5-p N p H 8-o-p-q G q , —C 6-p N p H 10-o-p-q G q , —C 7-p N p H 12-o-p-q G q , —C 8-p N p H 14-o-p-q G q , —C 9-p N p H 16-o-p-q G q , —C 10-p N p H 18-o-p-q G q , —C 5-p O p H 8-o-2p-q G q , —C 6-p O p H 10-o-2p-q G q , —C 7-p O p H 12-o-2p-q G q , —C 8-p O p H 14-o-2p-q G q , —C 9-p O p H 16-o-2p-q G q , —C 10-p O p H 18-o-2p-q G q , —C 5-p S p H 8-o-2p-q G q , —C 6-p S p H 10-o-2p-q G q , —C 7-p S p H 12-o-2p-q G q , —C 8-p S p H 14-o-2p- q G q , —C 9-p S p H 16-o-2p-q G q , —C 10-p S p H 18-o-2p-q G q , —C 5-p O l N p H 8-o-p-2l-q G q , —C 6-p O l N p H 10-o-p-2l- q G q , —C 7-p O l N p H 12-o-p-2l-q G q , —C 8-p O l N p H 14-o-p-2l-q G q , —C 9-p O l N p H 16-o-p-2l-q G q , —C 10-p O l N p H 18-o-p-2l- q G q , —C 5-p S l N p H 8-o-p-2l-q G q , —C 6-p S l N p H 10-o-p-2l-q G q , —C 7-p S l N p H 12-o-p-2l-q G q , —C 8-p S l N p H 14-o-p-2l-q G q , —C 9-p S l N p H 16-o-p-2l-q G q , —C 10-p S l N p H 18-o-p-2l-q G q ;

wherein

l=1,2,3, or 4

n=1, 2, 3, 4, 5, 6, 7, 8, 9, or 10

m=1, 2, 3, 4, 5, 6, 7, 8, 9, or 10

o=−1, 2, 3, 5, 7, or 9

p=1, 2, 3, 4, 5, or 6

q=1, 2, 3, 4, or 5;

wherein each G a is independently selected from

—H, -Alkyl, -Aryl, —SO 3 H, —SO 3 − , —PO 3 H 2 , —OH, -OAlkyl, —OOH, -OOAlkyl, —SH, -SAlkyl, —NH 2 , -NHAlkyl, -NAlkyl 2 , -NAlkyl 3 + , -NG b 2 , -NG b 3 + , —CHO, —COOH, -COOAlkyl, —CN, —CONH 2 , -CONHAlkyl, -CONAlkyl 2 , -Heteroaryl, -Heterocycyl, -NOG b , -N + OAlkyl, —F, —Cl—, and —Br;

wherein each G b is independently selected from

—H, -Alkyl, -Aryl, —SO 3 H, —SO 3 − , —PO 3 H 2 , —OH, -OAlkyl, —OOH, -OOAlkyl, —SH, -SAlkyl, —NH 2 , -NHAlkyl, -NAlkyl 2 , -NAlkyl 3 + , —CHO, —COOH, -COOAlkyl, —CN, —CONH 2 , -CONHAlkyl, -CONAlkyl 2 , -Heteroaryl, =Heterocycyl, -N + OAlkyl, —F, —Cl—, and —Br.

16. The low molecular weight aromatic compound of claim 1 , wherein the compound corresponds in structure to one of Formulas (1.1)-(1.10):

or a quinone form thereof.

17. A composition comprising at least two substituted low molecular weight aromatic compounds according to claim 1 .

18. The composition of claim 17 , wherein the at least two substituted low molecular weight aromatic compounds are characterized by the following:

(a) at least one compound according to Formula (1);

(b) at least one compound according to Formula (2); and/or

(c) at least one compound according to Formula (3).

19. The composition of claim 18 , wherein the at least two compounds are distinctly substituted.

20. The composition of claim 18 , wherein each of the at least two compounds comprises at least two, groups selected from sulfonyl; optionally substituted C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; and optionally substituted amine.

21. A method for preparing a substituted low molecular weight aromatic compound of claim 1 , comprising the steps of:

(1) providing a starting material;

(2) subjecting the starting material to a process suitable to obtain at least one low molecular weight precursor compound;

(3) isolating and optionally modifying the at least one low molecular weight precursor compound; thereby obtaining at least one low molecular weight aromatic precursor compound;

(4) subjecting the at least one low molecular weight precursor compound to a sulfonation reaction, wherein one or more substituents are introduced into the at least one low molecular weight aromatic precursor compound; thereby obtaining the at least one substituted low molecular weight aromatic compound;

wherein the starting material is selected from lignocellulosic material, crude oil, coal or pure organic substances.

22. The method of claim 21 , wherein the starting material is lignocellulosic material and the method comprises the followings steps:

(1) subjecting the lignocellulosic material to a pulping process; thereby obtaining modified lignin-derived components;

(2)isolating the modified lignin-derived components;

(3) subjecting the modified lignin-derived components to a chemical decomposition step; thereby obtaining the at least one low molecular weight precursor compound;

(4)isolating and optionally modifying the at least one low molecular weight precursor compound; thereby obtaining the at least one low molecular weight aromatic precursor compound; and

(5) subjecting the at least one low molecular weight aromatic precursor compound to a substitution reaction, wherein one or more substituents are introduced into the at least one low molecular weight aromatic precursor compound; thereby obtaining the at least one substituted low molecular weight aromatic compound.

23. The method of claim 22 , wherein step (1) further comprises the sub-steps of:

(1.1) providing a lignocellulosic material;

(1.2) subjecting the lignocellulosic material to (a) a Kraft process or (b) a sulfite process; and

(1.3) optionally separating the pulp from the process stream obtainable from the pulping process in sub-step (1.2).

24. The method of claim 22 , wherein step (3) comprises:

(a) oxidative cracking (cracking and oxidizing) of the modified lignin-derived components in the presence of a heterogeneous or homogeneous catalyst comprising a metal ion or a metalloid component; or

(b) reductive cracking (cracking and reducing) of the modified lignin-derived components in the presence of a heterogeneous or homogeneous catalyst comprising a metal ion or metalloid component; or

(c) subjecting the modified lignin-derived components to electro-oxidation in alkaline or acidic solution.

25. An aminated and/or sulfonated and/or otherwise substituted and optionally further derivatized low molecular weight aromatic compound prepared by the method of claim 21 , wherein the aminated and/or sulfonated and/or otherwise substituted low molecular weight aromatic compound corresponds in structure to Formula (1)-(3):

wherein each R 1 -R 4 in Formula (1), each of R 1 -R 6 in Formula (2) and each of R 1 -R 8 in Formula (3)

is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl, optionally comprising at least one heteroatom selected from N, O and S; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; halogen; optionally substituted amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl; cyanide and sulfonyl (—SO 3 H), and/or

wherein any two of adjacent substituents R 1 and R 2 and/or R 3 and R 4 of Formula (1) or any two of adjacent substituents of R 1 and R 2 and/or R 3 to R 6 of formula (2) or any two of adjacent substituents of R 1 -R 4 and/or R 5 -R 8 of formula (3) form at least one optionally substituted cyclic ring system,

provided that at least one of R 1 -R 4 in Formula (1), at least one of R 1 -R 6 in Formula (2) and/or at least one of R 1 -R 84 in Formula (3) is selected from optionally substituted amine; sulfonyl; and optionally substituted C 1-6 alkyl optionally comprising at least one heteroatom selected from N, O and S.

26. A redox flow battery electrolyte solution; comprising the substituted and optionally further derivatized low molecular weight aromatic compound of claim 1 dissolved or suspended in a suitable solvent.

27. A redox flow battery; comprising at least one substituted and optionally further derivatized low molecular weight aromatic compound of claim 1 .

28. The redox flow battery of claim 27 , wherein the redox flow battery comprises a first optionally aqueous electrolyte solution comprising a first redox active electrolyte; a first electrode in contact with the first optionally aqueous electrolyte solution; a second optionally aqueous electrolyte solution comprising a second redox active electrolyte; a second electrode in contact with the second optionally aqueous electrolyte solution; wherein the first redox active electrolyte comprises the at least one substituted and optionally further derivatized low molecular weight aromatic compound.

29. The redox flow battery of claim 27 , wherein the redox flow battery comprises (a) a first half-cell comprising a first electrode in contact with a first optionally aqueous electrolyte solution; and (b) a second half-cell comprising a second electrode in contact with a second optionally aqueous electrolyte solution comprising a second redox active electrolyte; wherein the second redox active electrolyte comprises either (i) an inorganic redox-active compound or inorganic redox-active compound couple as an electrolyte or (ii) the at least one substituted and optionally further derivatized low molecular weight aromatic compound.

30. The redox flow battery of claim 27 , wherein the redox flow battery comprises (a) a first half-cell comprising a first electrode in contact with a first optionally aqueous electrolyte solution; and (b) a second half-cell comprising a second electrode in contact with a second optionally aqueous electrolyte solution comprising a second redox active electrolyte; wherein the second redox active electrolyte comprises the at least one substituted and optionally further derivatized low molecular weight aromatic compound.