Process for the preparation of 3,3-dimethylbutanal
3,3-Dimethylbutanal is prepared from 3,3-dimethybutanol. Intermediate 3,3-dimethylbutanol is obtained by reacting ethylene, isopropylene and a mineral acid to produce a 3,3-dimethylbutyl ester which is hydrolyzed to the alcohol. The hydrolysis step is effectively carried out by reactive distillation. Alternatively, 3,3-dimethylbutanal is prepared from 3,3-dimethylbutanol obtained by reduction of the corresponding carboxylic acid or 1,2-epoxy-3,3-dimethylbutane, or by hydrolysis of 1-halo-3,3-dimethylbutane. Fixed bed gas phase and stirred tank liquid phase processes are provided for converted 3,3-dimethylbutanol to 3,3-dimethylbutanal by catalytic dehydrogenation.
1. A process for the preparation of 3,3-dimethylbutanal comprising:
preparing a slurry comprising a particulate dehydrogenation catalyst and 3,3-dimethylbutanol;
converting 3,3-dimethylbutanol to 3,3-dimethylbutanal by catalytic dehydrogenation in said slurry, thereby producing a dehydrogenation reaction product slurry comprising said catalyst and 3,3-dimethylbutanal; and
recovering 3,3-dimethylbutanal from the dehydrogenation reaction product slurry.
2. A process as set forth in claim 1 wherein said catalyst is selected from the group consisting of copper oxide, a reduced form of copper, zinc oxide, silver, gold, platinum, palladium and a platinum/tin alloy.
3. A process as set forth in claim 2 wherein said catalyst comprises a reduced form of copper.
4. A process as set forth in claim 1 wherein 3,3-dimethylbutanal produced in said catalytic dehydrogenation is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.
5. A process for the preparation of 3,3-dimethylbutanal comprising:
contacting 3,3-dimethylbutanoic acid or an ester thereof with a reducing agent, thereby producing 3,3-dimethylbutanol; and
converting 3,3-dimethylbutanol to 3,3-dimethylbutanal.
6. A process as set forth in claim 5 wherein 3,3-dimethylbutanoic acid or an ester thereof is contacted with a reducing agent selected from the group consisting of an alkali metal borohydride, and lithium aluminum hydride.
7. A process as set forth in claim 5 wherein 3,3-dimethylbutanoic acid or an ester thereof is reduced to 3,3-dimethylbutanol by catalytic hydrogenation.
8. A process as set forth in claim 5 wherein 3,3-dimethylbutanoic acid is contacted with lithium aluminum hydride.
9. A process as set forth in claim 5 wherein 3,3-dimethylbutanoic acid is contacted with sodium borohydride.
10. A process as set forth in claim 5 wherein 3,3-dimethylbutanol is contacted with an oxidizing agent for the oxidation of the alcohol to 3,3-dimethylbutanal.
11. A process as set forth in claim 10 wherein said oxidizing agent comprises copper oxide effective for stoichiometric oxidation of an alcohol to a corresponding aldehyde.
12. A process as set forth in claim 5 wherein 3,3-dimethylbutanol is contacted with a catalyst effective for dehydrogenation of 3,3-dimethylbutanol to 3,3-dimethylbutanal.
13. A process as set forth in claim 12 wherein said catalyst is effective for the anaerobic dehydrogenation of 3,3-dimethylbutanol, said catalyst being contacted with 3,3-dimethylbutanol in the substantial absence of molecular oxygen.
14. A process as set forth in claim 12 wherein said catalyst is effective for the oxidative dehydrogenation of 3,3-dimethylbutanol, said catalyst being contacted with 3,3-dimethylbutanol and molecular oxygen.
15. A process as set forth in claim 12 wherein said catalyst comprises an active phase comprising a reduced form of copper obtained in a stoichiometric redox reaction between copper oxide and 3,3-dimethylbutanol.
16. A process as set forth in claim 12 wherein said catalyst comprises an active phase comprising a reduced form of copper obtained by contacting copper oxide with a reducing agent selected from the group consisting of molecular hydrogen, sodium borohydride, and hydrazine.
17. A process as set forth in claim 12 wherein vapor phase 3,3-dimethylbutanol is passed over a bed comprising a catalyst for the dehydrogenation of 3,3-dimethylbutanol to 3,3-dimethylbutanal.
18. A process as set forth in claim 17 wherein said catalyst is effective for the anaerobic dehydrogenation of 3,3-dimethylbutanol, said vapor phase being substantially free of molecular oxygen.
19. A process as set forth in claim 17 wherein said catalyst is effective for the oxidative dehydrogenation of 3,3-dimethylbutanol, said vapor phase comprising molecular oxygen.
20. A process as set forth in claim 5 wherein said 3,3-dimethylbutanal is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.
21. A process for the preparation of 3,3-dimethylbutanal comprising:
preparing 3,3-dimethylbutanol, the preparation of 3,3-dimethylbutanol comprising hydrolysis of 1-halo-3,3-dimethylbutane or 1-acyloxy-3,3-dimethylbutane in the presence of a base; and
converting 3,3-dimethylbutanol to 3,3-dimethylbutanal.
22. A process as set forth in claim 21 wherein preparation of 3,3-dimethylbutanol comprises hydrolysis of 1-halo-3,3-dimethylbutane.
23. A process as set forth in claim 22 wherein 3,3-dimethylbutanol is prepared by hydrolyzing a substrate selected from the group consisting of 1-chloro-3,3-dimethylbutane, 1-bromo-3,3-dimethylbutane and 1-iodo-3,3-dimethylbutane.
24. A process as set forth in claim 23 wherein said substrate is contacted with an aqueous base at a temperature effective for the hydrolysis.
25. A process as set forth in claim 24 wherein 3,3-dimethylbutanol is contacted with a metal oxide at a temperature in excess of about 200° C.
26. A process as set forth in claim 25 wherein 3,3-dimethylbutanol is contacted with a metal oxide at a temperature of between about 200° C. and about 400° C.
27. A process as set forth in claim 23 wherein 3,3-dimethylbutanol is contacted with an oxidizing agent for the oxidation of the alcohol to 3,3-dimethylbutanal.
28. A process as set forth in claim 27 wherein said oxidizing agent comprises copper oxide effective for stoichiometric oxidation of an alcohol to a corresponding aldehyde.
29. A process as set forth in claim 23 wherein 3,3-dimethylbutanol is contacted with a catalyst effective for dehydrogenation of 3,3-dimethylbutanol to 3,3-dimethylbutanal.
30. A process as set forth in claim 29 wherein said catalyst is effective for the anaerobic dehydrogenation of 3,3-dimethylbutanol, said catalyst being contacted with 3,3-dimethylbutanol in the substantial absence of molecular oxygen.
31. A process as set forth in claim 29 wherein said catalyst is effective for the oxidative dehydrogenation of 3,3-dimethylbutanol, said catalyst being contacted with 3,3-dimethylbutanol and molecular oxygen.
32. A process as set forth in claim 29 wherein said catalyst comprises an active phase comprising a reduced form of copper obtained in a stoichiometric redox reaction between copper oxide and 3,3-dimethylbutanol.
33. A process as set forth in claim 29 wherein said catalyst comprises an active phase comprising a reduced form of copper obtained by contacting copper oxide with a reducing agent selected from the group consisting of molecular hydrogen, sodium borohydride, and hydrazine.
34. A process as set forth in claim 29 wherein vapor phase 3,3-dimethylbutanol is passed over a bed comprising a catalyst for the dehydrogenation of 3,3-dimethylbutanol to 3,3-dimethylbutanal.
35. A process as set forth in claim 34 wherein said catalyst is effective for the anaerobic dehydrogenation of 3,3-dimethylbutanol, said vapor phase being substantially free of molecular oxygen.
36. A process as set forth in claim 34 wherein said catalyst is effective for the oxidative dehydrogenation of 3,3-dimethylbutanol, said vapor phase comprising molecular oxygen.
37. A process as set forth in claim 23 wherein said 3,3-dimethylbutanal is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.
38. A process as set forth in claim 21 wherein the preparation of 3,3-dimethylbutanol comprises:
reaction of said 1-halo-3,3-dimethylbutane with a salt of an organic acid, thereby producing an ester of 3,3-dimethylbutanol; and
hydrolyzing said ester in the presence of a base to produce 3,3-dimethylbutanol.
39. A process as set forth in claim 21 wherein said 3,3-dimethylbutanal is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.
40. A process for the preparation of 3,3-dimethylbutanal comprising:
reducing 1,2-epoxy-3,3-dimethylbutane oxide to 3,3-dimethylbutanol; and
converting 3,3-dimethylbutanol to 3,3-dimethylbutanal.
41. A process as set forth in claim 40 wherein said 1,2-epoxy-3,3-dimethylbutane is reduced to 3,3-dimethylbutanol by catalytic hydrogenation.
42. A process as set forth in claim 40 wherein said 3,3-dimethylbutanal is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.
43. A process for the preparation of 3,3-dimethylbutanal comprising:
reacting a t-butyl organometallic compound with ethylene oxide to form 3,3-dimethylbutanol; and
converting 3,3-dimethylbutanol to 3,3-dimethylbutanal.
44. A process as set forth in claim 43 wherein said organometallic compound is selected from the group consisting of R-G and R—Li wherein R is t-butyl and G is selected from the group consisting of MgCl and MgBr.
45. A process as set forth in claim 43 wherein said 3,3-dimethylbutanal is reacted with L-α-aspartyl-L-phenylalanine 1-methyl ester in the presence of a reducing agent to produce N-[N-(3,3-dimethybutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester.