Process for preparing amines
The present invention refers to a process for preparing amines comprising reacting a compound of the formula R 1 —CO—R 2 comprising a carbonyl moiety with a amine compound of the formula HNR 3 R 4 and carbon monoxide in the presence of a catalyst.
1. A process for preparing an amine of formula I comprising reductive amination of a carbonyl compound of the formula II with an amine compound of the formula III and carbon monoxide as reductant in the presence of a catalyst and without introducing hydrogen (H 2 ) from an external hydrogen source to yield said amine of formula I:
wherein:
R 1 and R 2 are each independently hydrogen or a substituent selected from the group consisting of C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthiol, arylthiol, C 1 -C 20 alkylsulfonyl, and C 1 -C 20 alkylsulfinyl, each of which is optionally substituted with one or more moieties selected from the group consisting of C 1 -C 10 alkyl, C 1 -C 10 alkoxy, aryl, and one or more functional groups selected from the group consisting of hydroxyl, thiol, thioether, ketone, aldehyde, ester, ether, amine, imine, amide, nitro, carboxylic acid, disulfide, carbonate, isocyanate, carbodiimide, carboalkoxy, carbamate, and halogen, wherein at least one of R 1 and R 2 is not hydrogen; and
R 3 and R 4 are each independently hydrogen or a substituent selected from the group consisting of C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthiol, arylthiol, C 1 -C 20 alkylsulfonyl, and C 1 -C 20 alkylsulfinyl, each of which is optionally substituted with one or more moieties selected from the group consisting of C 1 -C 10 alkyl, C 1 -C 10 alkoxy, aryl, and one or more functional groups selected from the group consisting of hydroxyl, thiol, thioether, ketone, aldehyde, ester, ether, amine, imine, amide, nitro, carboxylic acid, disulfide, carbonate, isocyanate, carbodiimide, carboalkoxy, carbamate, and halogen, wherein at least one of R 3 and R 4 is not hydrogen.
2. The process according to claim 1 , wherein the reaction is carried out in a solvent, selected from aliphatic, cycloaliphatic or aromatic solvents, esters, ethers or mixtures thereof.
3. The process according to claim 1 , wherein the reaction is carried out at a reaction pressure of 1 to 200 bar.
4. The process according to claim 1 , wherein the reaction is carried out at an elevated temperature between 50° to 350° C.
5. The process according to claim 1 , wherein the amine of formula I is obtained in a yield of at least 93%.