Amino catalyzed production of hydrogen from silylated derivatives as hydrogen carrier

1. A method for producing hydrogen comprising the steps of:

i) contacting a compound (C) comprising one or more groups Si—H with an amine based catalyst in a solvent selected from an alcohol or an aqueous solution, thereby forming hydrogen and a by-product (C1);

wherein said amine based catalyst is selected from:

(a)—a compound of formula R a R b R c N wherein:

R a and R b are each, independently selected from the group consisting of H, C 1 -C 6 alkyl, C 6 -C 10 aryl, aralkyl, 5 to 7 membered heteroaryl,and 5 to 7 membered heterocyclyl;

wherein said alkyl or aryl groups are optionally substituted by one to three R d ;

R d is selected from the group consisting of Cl, Br, I, F, OH, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 6 -C 10 aryl, aralkyl, NO 2 , NH 2 , CN, COOH;

R c is aralkyl; or

(b)—a polymer-supported catalyst bearing one or more groups selected from the group consisiting of NR a R b , and R a R b wherein:

R a and R b are each, independently selected from the group consisting of H, C 1 -C 6 alkyl, C 6 -C 10 aryl, aralkyl, 5 to 7 membered heteroaryl and 5 to 7 membered heterocyclyl;

wherein said alkyl or aryl groups are optionally substituted by one or three R d ;

R d is selected from the group consisting of Cl, Br, I, F, OH, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 6 -C 10 aryl,aralkyl, NO 2 , NH 2 , CN and COOH;

ii) recovering the obtained hydrogen.

2. The method of claim 1 , wherein R a is H.

3. The method of claim 2 , wherein R b is H.

4. The method of claim 1 , wherein the amine based catalyst is a benzylamine optionally substituted by one to three R d .

5. The method of claim 1 , wherein the amine based catalyst is benzylamine.

6. The method of claim 1 , wherein the polymer supported catalyst is (Aminomethyl)polystyrene.

7. The method of claim 1 , wherein the molar ratio of the amine based catalyst relative to compound (C) ranges from 0.01 to 0.1 equivalents.

8. The method of claim 1 , wherein the alcohol is methanol.

9. The method of claim 1 , wherein the aqueous solution is a solution of alkaline or alkaline-earth metal hydroxide.

10. The method of claim 9 , wherein the aqueous solution is a potassium hydroxide solution.

11. The method of claim 1 , wherein the aqueous solution is a solution of mineral acid.

12. The method of claim 11 , wherein the mineral acid is HCl.

13. The method of claim 1 , wherein the aqueous solution is water.

14. The method of claim 1 , wherein the compound (C) comprises one or more monomer units of formula (A):

wherein:

R is selected from the group consisting of a bond, C 1 -C 6 alkylene and (C 1 -C 4 alkylene) m -Z—(C 1 -C 4 alkylene) q ;

Z is selected from the group consisting of O, NR 10 , S(O) y , CR 10 ═CR 10 , C≡C, C 6 -C 10 arylene, 5-10 membered heteroarylene and C 3 -C 6 cycloalkylene;

R 1 , R 2 are each independently selected from the group consisting of H, halogen, C 1 -C 10 alkyl, C 3 -C 10 cycloalkyl, C 6 -C 12 aryl, aralkyl, 5 to 10-membered heteroaryl, OR 3 and NR 4 R 5 , SiR 6 R 7 R 8 , wherein said aryl groups are optionally substituted by one to three R 9 groups;

R 3 is selected from the group consisting of H, C 1 -C 6 alkyl, C 6 -C 10 aryl and aralkyl;

R 4 , R 5 are each independently selected from the group consisting of H, C 1 -C 6 alkyl, C 6 -C 10 aryl and aralkyl;

R 6 , R 7 , R 8 are each independently selected from the group consisting of H, OR 3 , C 1 -C 6 alkyl, C 6 -C 10 aryl and aralkyl;

R 9 is selected from the group consisting of halogen, C 1 -C 10 alkyl, OR 10 , NO 2 , NR 11 R 12 , CN, C(═O)R 10 , C(═O)OR 10 and S(═O)CH 3 , wherein said alkyl group is optionally substituted by one or more halogen;

R 10 is H or C 1 -C 3 alkyl;

R 11 , R 12 are each independently selected from the group consisting of H and C 1 -C 10 alkyl;

m, q are 0 or 1;

y is 0, 1 or 2;

n, p are intengers each representing the number of repeating units, with

n being superior or equal than 1, and

p being 0 or 1;

r is 0 or 1 provided that p+r is 0 or 1, it being understood that when the solvent is an alcohol r is 0.

15. The method of claim 14 , wherein p is 0.

16. The method of claim 15 , wherein r is 1.

17. The method of claim 16 , wherein the monomer unit is of formula (Ia):

18. The method of claim 17 , wherein the compound (C) is polymethylhydrosiloxane (PHMS).

19. The method of claim 15 , wherein r is 0.

20. The method of claim 19 , wherein the monomer unit is of formula (Ib):

21. The method of claim 1 , wherein the compound (C) is PhSiH 3 .

22. The method of claim 20 , wherein the compound (C) comprising a monomer unit of formula (Ib) is C(SiH 3 ) 4 .

23. The method of claim 14 , wherein p is 1 and r is 0.

24. The method of claim 23 , wherein the monomer unit is of formula (Ic):

wherein R is C 1 -C 6 alkylene.

25. The method of claim 24 , wherein the compound (C) comprising a monomer unit of formula (Ic) is H 3 Si(CH 2 ) 2 SiH 3 .

26. The method of claim 20 , wherein the solvent is an aqueous solution and the amine based catalyst is a benzylamine of formula (B):

wherein x is 0, 1, 2 or 3 and R d is as defined in claim 1 .

27. The method of claim 26 , further comprising the following subsequent recycling steps:

iii) contacting the by-product (C1) with an acyl halide;

iv) contacting the obtained product with a metal hydride, thereby regenerating compound (C).

28. A composition comprising a compound (C), as defined in claim 1 , the amine based catalyst as defined in claim 1 and the solvent as defined in claim 1 .

29. A use of a composition of claim 28 for producing hydrogen comprising the step of contacting the compound (C), the amine based catalyst and the solvent.

30. A device for producing hydrogen according to claim 1 , said device comprising a reaction chamber comprising:

a compound (C)/solvent mixture inlet;

an hydrogen outlet;

a by-product collector; and

a surface intended to be in contact with the compound (C)/solvent mixture, as defined in claim 1 , coated with a polymer supported catalyst as defined in claim 1 .

31. The device of claim 30 , further comprising a mixing chamber for mixing the compound (C) with the solvent, wherein the mixing chamber is connected to the reaction chamber.

32. The device of claim 30 , further comprising a by-product collection chamber, wherein the collection chamber is connected to the reaction chamber.

33. The device of claim 30 , further comprising a second chamber comprising:

an outer envelope;

an internal wall separating said chamber into two distinct compartments, namely:

a first compartment containing the compound (C)/solvent mixture to be introduced in the reaction chamber; and

a second compartment containing the by-product (C1) collected from the reaction chamber;

the first and second compartment being each connected to the reaction chamber; and

means for moving the internal wall relative to the outer envelope, so as to make the respective volumes of each compartment to vary.