Claims
- 1. A method for preparing omega-aminoalkanoic acids which conprises:
- a. simultaneously contacting at a temperature between about 0.degree. to 40.degree.C. a solution containing a C.sub.7 to C.sub.20 cycloalkene, a denitrating agent and an aprotic organic solvent with dinitrogen tetroxide and oxygen, wherein said denitrating agent is selected from the group consisting of 2-pyrrolidinones, ##EQU7## where R.sup.1, R.sup.2, R.sup.6, R.sup.7, R.sup.8 and R.sup.9 are alkyl of from 1 to 5 carbons and R.sup.3, R.sup.4 and R.sup.5 are hydrogen or alkyl of from 1 to 5 carbons, where the mole ratio of cycloalkene to denitrating agent is above about 0.5:1 to about 2:1, thereby forming 2-nitrocycloalkanone,
- b. contacting 2-nitrocycloalkanone with an alcohol, wherein said alcohol is a primary or secondary alcohol corresponding to the formula R'OH where R' is an alkyl group of from 1 to 20 carbon atoms, in a non-aqueous environment at a temperature of from about 20.degree. to 200.degree.C. thereby forming an alkyl omega-nitroalkanoate,
- c. contacting said alkyl omega-nitroalkanoate with hydrogen and a Group VIII metal catalyst at a temperature of from 20.degree. to 300.degree.C. under a hydrogen pressure of 500 to 1500 p.s.i.g. thereby forming an alkyl omega-aminoalkanoate, and
- d. contacting said alkyl omega-aminoalkanoate with water at a temperature of from 150.degree. to 300.degree.C.
- 2. A method according to claim 1 wherein said cycloalkene has from 7 to 12 carbon atoms.
- 3. A method according to claim 1 wherein said cycloalkene is cyclooctene.
- 4. A method according to claim 1 wherein said cycloalkene is cyclododecene.
- 5. A method according to claim 1 wherein said denitrating agent is dimethyl formamide.
- 6. A method according to claim 1 wherein said organic solvent has a boiling point of between about 30.degree. to 100.degree.C.
- 7. A method according to claim 1 wherein said contacting in (a) is conducted at a temperature between about 5.degree. to 15.degree.C.
- 8. A method according to claim 1 wherein the mole ratio of said denitrating agent to cycloalkene is about 0.8:1 to 1.3:1.
- 9. A method according to claim 1 wherein said organic solvent is carbon tetrachloride.
- 10. A method according to claim 1 wherein said organic solvent is benzene.
- 11. A method according to claim 1 wherein said alcohol in (b) is methanol.
- 12. A method according to claim 1 wherein step (b) is conducted thermally at a temperature of from 100.degree. to 190.degree.C.
- 13. A method according to claim 1 wherein step (b) is conducted in the presence of a basic catalyst at a temperature of from 60.degree. to 100.degree.C.
- 14. A method according to claim 13 wherein said catalyst is potassium fluoride.
- 15. A method according to claim 13 wherein said catalyst is sodium carbonate.
- 16. A method according to claim 1 wherein the mole ratio of 2-nitrocycloalkanone to alcohol in step (b) ranges from 1:1 to about 1:100.
- 17. A method according to claim 1 wherein said alkyl omega-nitroalkanoate in (b) is methyl 8-nitrooctanoate.
- 18. A method according to claim 1 wherein said alkyl omega-nitroalkanoate in (b) is methyl 12-nitrododecanoate.
- 19. A method according to claim 1 wherein said Group VIII metal catalyst is platinum oxide.
- 20. A method according to claim 1 wherein said Group VIII metal catalyst is nickel on kieselguhr.
- 21. A method according to claim 1 wherein said contacting in (c) is conducted at a temperature of 100.degree. to 220.degree.C.
- 22. A method according to claim 1 wherein said aminoester in (c) is methyl 8-aminooctanoate.
- 23. A method according to claim 1 wherein said aminoester in (c) is methyl 12-aminododecanoate.
- 24. A method according to claim 1 wherein from 1 to 200 moles of water per mole of said aminoester is employed in (d).
- 25. A method according to claim 1 wherein said contacting in (d) is at a pressure of 50 to 1200 p.s.i.g.
- 26. A method according to claim 1 wherein said acid is 12-aminododecanoic acid.
- 27. A method according to claim 1 wherein said acid is 8-aminooctanoic acid.
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of our co-pending application Ser. No. 206,197, filed Dec. 8, 1971 now U.S. Pat. No. 3,816,404.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
2998437 |
Benton |
Aug 1961 |
|
3557166 |
Lachowicz et al. |
Jan 1971 |
|
3816404 |
Kablaoui et al. |
Jun 1974 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
206197 |
Dec 1971 |
|