Method for the vinylation of amides

Patent metadata

Field	Value
Publication number	US-9249094-B2
Application number	US-74442808-A
Country	US
Kind code	B2
Filing date	Dec 8, 2008
Priority date	Dec 11, 2007
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A process for preparing an N-vinyl compound by vinylating a compound having at least one nitrogen atom (referred to hereinafter as compound for short) with acetylene, wherein
before the vinylation, the compound is reacted with an alkali metal hydroxide in a reaction zone and the mean residence time of the alkali metal hydroxide and of the compound in the reaction zone is less than 6 minutes.

First claim

The invention claimed is:

1. A process for preparing an N-vinyl compound, comprising vinylating a compound having at least one nitrogen atom with acetylene, wherein
before the vinylation, the compound is reacted with an alkali metal hydroxide in a reaction zone and
a mean residence time of the alkali metal hydroxide and of the compound in the reaction zone is less than 5 minutes.

2. The process according to claim 1 , wherein the N-vinyl compound is an N-vinylamide.

3. The process according to claim 1 , wherein the N-vinyl compound is N-vinyl-N-methylacetamide or N-vinylpyrrolidone.

4. The process according to claim 1 , wherein the alkali metal hydroxide is potassium hydroxide.

5. The process according to claim 1 , wherein the alkali metal hydroxide is in the form of an aqueous solution.

6. The process according to claim 1 , wherein the reaction is effected in a column comprising the reaction zone.

7. The process according to claim 6 , wherein the column has random packing and has at least 2 theoretical plates.

8. The process according to claim 6 , wherein the alkali metal hydroxide and the compound are added in an upper third of the column.

9. The process according to claim 6 , wherein the column is operated at a pressure of from 1 mbar to 1 bar and a temperature of from 20 to 250° C.

10. The process according to claim 1 , wherein the mean residence time of the alkali metal hydroxide and of the compound in the reaction zone is from 50 to 200 seconds.

11. The process according to claim 1 , wherein the vinylation of the compound is effected in a subsequent process.

12. The process according to claim 1 , wherein, said alkali metal hydroxide is in the form of an aqueous solution having an alkali metal hydroxide content of from 5 to 90% by weight.

13. The process according to claim 1 , wherein, said alkali metal hydroxide is in the form of an aqueous solution having an alkali metal hydroxide content of from 30 to 60% by weight.

14. The process according to claim 1 , wherein, said alkali metal hydroxide is in the form of an aqueous solution having an alkali metal hydroxide content of from 45 to 55% by weight.

15. The process according to claim 6 , wherein said column has from 2 to 100 theoretical plates.

16. The process according to claim 6 , wherein said column has from 3 to 20 theoretical plates.

17. The process according to claim 1 , wherein an amount of alkali metal hydroxide is such that from 0.25 to 25% by weight of said compound is present in the form of an alkali metal salt.

18. The process according to claim 1 , wherein an amount of alkali metal hydroxide is such that from 1 to 10% by weight of said compound is present in the form of an alkali metal salt.

Assignees

• Vogelsang Regina
• Kaeshammer Stefan
• Staffel Wolfgang
• Eiden Ulrich
• Brand Alexandra
• Tuttelberg Lembit
• Basf Se

Inventors

• Vogelsang Regina
• Kaeshammer Stefan
• Staffel Wolfgang
• Eiden Ulrich
• Brand Alexandra
• Tuttelberg Lembit

Classifications

• C07D207/267 Primary

  with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atom · CPC title