US4684758A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of 2,5-dimethyl-2,4-hexadiene
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1986-07-31
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Granted: 1987-08-04
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Expires: 2006-07-31
Abstract
Abstract 2,5-Dimethyl-2,4-hexadiene which is an intermediate for preparing agricultural chemicals, insecticides or medicines, is prepared by bringing isobutylene and/or tert.-butyl alcohol into contact with isobutyl aldehyde in a gaseous phase at a temperature of 150 DEG -350 DEG C. in the presence of a niobic acid catalyst.
Inventors
- 👤 Yasuhiko Higashio
- 👤 Kazuteru Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:39
CPC Classifications
C; C07; C07C; C07C1/00; C07C1/20; C07C2/00; C07C2/86; C07C2/862; C07C2/867; C07C2521/00; C07C2521/16; C07C2523/00; C07C2523/16; C07C2523/20; C07C2527/00; C07C2527/14; C07C2527/16; C07C2527/167; C07C2527/173; C07C2529/00; C07C2529/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
34 words
A method for preparing 2,5-dimethyl-2,4-hexadiene by bringing isobutylene and/or tert.-butyl alcohol into contact with isobutyl aldehyde in a gaseous phase in the presence of a niobic acid catalyst at a temperature of 150°-350° C.
Claim 2
Independent Claim
34 words
A method for preparing 2,5-dimethyl-2,4-hexadiene by bringing isobutylene and/or tert.-butyl alcohol into contact with isobutyl aldehyde in a gaseous phase in the presence of a niobic acid catalyst at a temperature of 150°-350° C.
Claim 3
Dependent Claim
22 words
A method according to claim 1 wherein isobutylene or tert.-butyl alcohol or a mixture thereof to isobutyl aldehyde is 1-10:1 in mol.
Claim 4
Dependent Claim
16 words
A method according to claim 1 wherein the catalyst is niobic acid pre-treated with mineral acid.
Claim 5
Dependent Claim
16 words
A method according to claim 3 wherein the mineral acid is sulfuric acid or phosphoric acid.
Claim 6
Dependent Claim
13 words
A method according to claim 1 wherein the contact is effected under pressure.
Claim 7
Dependent Claim
14 words
A method according to claim 1 wherein the contact is effected at atmospheric pressure.
Claim 8
Dependent Claim
17 words
A method according to claim 1 wherein the contact is effected at a temperature of 200°-350° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-03 | 1991-02-02 | 1991-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-03 | 1995-02-02 | 1995-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-03 | 1999-02-02 | 1999-08-04 | $7700.00 | Window Closed / Lapsed |