PROCESS FOR CONVERTING AMIDE TO AMINE
The present invention relates to a process for converting an amide into an amine comprising hydrogenation of the amide at a temperature not higher than 130° C. and a hydrogen pressure not higher than 50 bar in the presence of a supported heterogeneous catalyst preparable by a method comprising depositing vanadium on a supported noble metal catalyst by impregnation.
1 . A process for converting an amide into an amine comprising hydrogenation of the amide at a temperature not higher than 130° C. and a hydrogen pressure not higher than 50 bar in the presence of a supported heterogeneous catalyst preparable by a method comprising depositing vanadium on a supported noble metal catalyst by impregnation.
2 . The process according to claim 1 , wherein the amide is of formula (I) and the amine is of formula (II),
wherein
R 1 is a group selected from linear or branched C1-C20 alkyl, and phenyl which is optionally substituted by a linear or branched C1-C4 alkyl,
R′ 1 is identical to R1 when R1 is a linear or branched C1-C20 alkyl and R′1 is cyclohexyl which is optionally substituted by a linear or branched C1-C4 alkyl when R1 is phenyl which is optionally substituted by a linear or branched C1-C4 alkyl,
R 2 and R 3 , independently from each other, are hydrogen, or linear or branched C1-C4 alkyl, or
R 2 and R 3 together with the nitrogen atom they attached to form a piperidine ring which is optionally substituted by a linear or branched C1-C4 alkyl.
3 . (canceled)
4 . (canceled)
5 . The process according to claim 1 , wherein the noble metal is selected from the group consisting of rhodium(Rh), platinum (Pt), ruthenium (Ru), and iridium (Ir).
6 . The process according to claim 1 , wherein the noble metal is present in amount from 1 wt. % to 10 wt. % in the supported heterogeneous catalyst, relative to the total weight of the supported heterogeneous catalyst.
7 . The process according to claim 1 , wherein vanadium is present in amount from 0.5 wt. % to 10 wt. % in the supported heterogeneous catalyst, relative to the total weight of the supported heterogeneous catalyst.
8 . The process according to claim 1 , wherein the molar ratio of the noble metal to vanadium is from 0.5 to 10.
9 . The process according to claim 1 , wherein the support for the supported heterogeneous catalyst is selected from alumina, silica and activated carbon.
10 . The process according to claim 1 , wherein the hydrogenation is carried out with the molar ratio of the noble metal in the supported heterogeneous catalyst to the amide from 0.5% to 35%.
11 . A process for converting an amide into an amine comprising:
(i) preparing a supported heterogeneous catalyst by a method comprising depositing vanadium on a supported noble metal catalyst by impregnation, and
(ii) causing hydrogenation of the amide at a temperature not higher than 130° C. and a hydrogen pressure not higher than 50 bar in the presence of the so-prepared supported heterogeneous catalyst to obtain the amine.
12 . The process according to claim 3 , wherein the amide is of formula (I) and the amine is of formula (II),
wherein
R 1 is a group selected from linear or branched C1-C20 alkyl, and phenyl which is optionally substituted by a linear or branched C1-C4 alkyl,
R′ 1 is identical to R 1 when R 1 is a linear or branched C1-C20 alkyl and R′ 1 is cyclohexyl which is optionally substituted by a linear or branched C1-C4 alkyl when R1 is phenyl which is optionally substituted by a linear or branched C1-C4 alkyl,
R 2 and R 3 , independently from each other, are hydrogen, or linear or branched C1-C4 alkyl, or
R 2 and R 3 together with the nitrogen atom they attached to form a piperidine ring which is optionally substituted by a linear or branched C1-C4 alkyl.
13 . The process according to claim 11 , wherein depositing vanadium on the supported noble metal catalyst comprises depositing a vanadium precursor on the supported noble metal catalyst by impregnation.
14 . The process according to claim 13 , wherein the vanadium precursor is selected from the group consisting of Vanadyl (IV) acetylacetonate and ammonium metavanadate.
15 . The process according to claim 11 , wherein depositing vanadium on a supported noble metal catalyst is carried out as follows:
i) dissolving a vanadium precursor in a solvent to obtain a vanadium-containing solution,
ii) adding the supported noble metal catalyst to the vanadium-containing solution to form an uniform mixture;
iii) evaporating the solvent to yield a powder;
iv) drying and calcining the powder to obtain the supported heterogeneous catalyst.
16 . The process according to claim 15 , wherein the solvent is selected from the group consisting of acetone, water, and ethanol.
17 . (canceled)
18 . (canceled)
19 . (canceled)
20 . (canceled)
21 . (canceled)
22 . (canceled)
23 . (canceled)
24 . (canceled)
25 . (canceled)
26 . A mixture comprising a first amine of formula (II) and an alcohol of formula (III):
wherein:
R′ 1 is cyclohexyl which is optionally substituted by a linear or branched C1-C4 alkyl;
R 2 and R 3 , independently from each other, are hydrogen, or linear or branched C1-C4 alkyl;
the molar ratio of the first amine to the alcohol is greater than 2.5.
27 . The mixture according to claim 5 , wherein R 3 is H.
28 . The mixture according to claim 26 , further comprising a second amine of formula (IV):
wherein R′ 1 is cyclohexyl which is optionally substituted by a linear or branched C1-C4 alkyl; and
R 2 is hydrogen, or linear or branched C1-C4 alkyl.
29 . The mixture according to claim 26 , wherein R 2 is H.
30 . The mixture according to claim 28 , wherein the molar ratio of the first amine to the second amine is greater than 5.
31 . The mixture according to any one of claim 26 , wherein R′ 1 is cyclohexyl.