Process for preparing amides from ketoximes
View Patent ↗The present invention is directed to a process for preparing amides. In particular, the process is directed to a process performable on the industrial scale, in which a ketoxime can be converted to a cyclic or acyclic amide by means of a Beckmann rearrangement using 2,4,6-trichloro-1,3,5-triazine as a catalyst in a nonpolar organic solvent.
1. A process for preparing an amide from a corresponding ketoxime, comprising:
providing a mixture of at least one ketoxime and cyanuric chloride in at least one nonpolar organic solvent; and
heating the mixture to react the at least one ketoxime,
wherein the at least one ketoxime is a cyclic ketoxime having a ring size of 6-12, the at least one nonpolar organic solvent has a logP value of 2-14, and the at least one nonpolar organic solvent does not consist exclusively of toluene when an amount of cyanuric chloride in the mixture is ≦5 mol %.
2. The process according to claim 1 ,
wherein
the mixture includes 0.5-30 mol % of cyanuric chloride based on an amount of the at least one ketoxime in the mixture.
3. The process according to claim 1 ,
wherein
the at least one nonpolar organic solvent comprises at least one selected from the group consisting of cyclooctane, hydrocumene and cyclododecane.
4. The process according to claim 1 ,
wherein
the providing of the mixture comprises providing a mixture of the at least one ketoxime, cyanuric chloride and a cocatalyst.
5. The process according to claim 1 ,
wherein
the heating comprises heating the mixture to react the at least one ketoxime at a temperature of 50-250° C.
6. The process according to claim 1 ,
wherein
the providing of the mixture and the heating of the mixture are performed in a continuous process.
7. The process according to claim 1 , wherein the at least one ketoxime comprises at least one cyclic ketoxime having a ring size of 6-9.
8. The process according to claim 7 , wherein the mixture includes 3-13 mol % of cyanuric chloride based on an amount of the at least one ketoxime in the mixture.
9. The process according to claim 1 , wherein the at least one ketoxime comprises at least one cyclic ketoxime having a ring size of 10-12.
10. The process according to claim 9 , wherein the at least one nonpolar organic solvent comprises one of cyclooctane and hydrocumene.
11. The process according to claim 9 , wherein the mixture includes 3-13 mol % of cyanuric chloride based on an amount of the at least one ketoxime in the mixture.
12. The process according to claim 1 , wherein the at least one ketoxime is at least one of cyclododecanone oxime and c-hexanone oxime.
13. The process according to claim 1 , wherein the mixture includes 1.5-13 mol % of cyanuric chloride based on an amount of the at least one cyclic ketoxime in the mixture.
14. The process according to claim 1 , wherein the mixture includes 2-6 mol % of cyanuric chloride based on an amount of the at least one acyclic ketoxime in the mixture.
15. The process according to claim 1 , wherein the heating comprises heating the mixture to react the at least one ketoxime at a temperature of 80-120° C.
16. The process according to claim 1 , wherein the heating comprises heating the mixture to react the at least one ketoxime at a temperature of 100-115° C.