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US4795847A
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Preparation of 2,6-dialkyl-naphthalenes
Assignee: Rain Carbon Germany GmbH
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Filing: 1988-02-02
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Granted: 1989-01-03
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Expires: 2008-02-02
Abstract
Abstract A process for the preparation of 2,6-dialkyl-naphthalenes comprising selectively alkylating naphthalene or 2-alkyl-naphthalene with alkylating agent in the presence of a zeolite catalyst at 250° to 345° C. which dialkyl-naphthalenes are useful for the preparation of naphthalene 2,6-dicarboxylic acid used to produce high-quality polyesters or polyamides.
Inventors
- 👤 Jens Weitkamp
- 👤 Marita Neuber
- 👤 Wilhelm Holtmann
- 👤 Gerd Collin
- 👤 Hans Spengler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:24
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/54; C07C2/64; C07C2/66; B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/40; C07C2/86; C07C2/862; C07C2/864; C07C2529/00; C07C2529/04; C07C2529/06; C07C2529/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
37 words
A process for the preparation of 2,6-dialkyl-naphthalenes comprising selectively alkylating naphthalene or 2-alkyl-naphthalene with a lower alcohol, dialkyl ether or alkyl halide as alkylating agent in the presence of a zeolite catalyst at 300° to 320° C.
Claim 2
Dependent Claim
37 words
A process for the preparation of 2,6-dialkyl-naphthalenes comprising selectively alkylating naphthalene or 2-alkyl-naphthalene with a lower alcohol, dialkyl ether or alkyl halide as alkylating agent in the presence of a zeolite catalyst at 300° to 320° C.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the alkylating agent is a methylating agent.
Claim 4
Dependent Claim
9 words
The process of claim 2 wherein 2-methyl-naphthalene is reacted.
Claim 5
Dependent Claim
11 words
The process of claim 1 wherein mixtures of methyl-naphthalenes are reacted.
Claim 6
Dependent Claim
16 words
The process of claim 1 wherein the zeolite has a spaciousness index of 1 to 12.
Claim 7
Dependent Claim
11 words
The process of claim 2 wherein the catalyst is ZSM-5 zeolite.
Claim 8
Dependent Claim
17 words
The method of claim 1 wherein the crystalline size of the zeolite is 0.01 to 20 μm.
Claim 9
Dependent Claim
17 words
The method of claim 1 wherein the crystalline size of the zeolite is 0.05 to 5 μm.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-03 | 1992-07-04 | 1993-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-03 | 1996-07-04 | 1997-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-03 | 2000-07-04 | 2001-01-03 | $7700.00 | Window Closed / Lapsed |