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US3894042A
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Preparation of indoles and catalyst compositions used in their preparation
Assignee: Teijin Ltd
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Filing: 1973-01-16
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Granted: 1975-07-08
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Expires: 1993-01-16
Abstract
Abstract In the process for preparing indoles by the vapor phase catalytic reaction of the 2-alkyl-and/or 2-alkenylanilines at an elevated temperature in the substantial absence of molecular oxygen; the improvement which comprises carrying out said vapor phase catalytic reaction in the presence of a catalyst comprising iron oxide and an alkali metal compound in the presence of steam.
Inventors
- 👤 Kunio Tanaka
- 👤 Toshio Fukada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:00
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/04; C07D209/08; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
18 words
IN THE PROCESS FOR PREPARING INDOLES BY THE VAPOR PHASE CATALYTIC REACTION OF COMPOUNDS OF THE FOLLOWING FORMULA:
Claim 2
Dependent Claim
18 words
IN THE PROCESS FOR PREPARING INDOLES BY THE VAPOR PHASE CATALYTIC REACTION OF COMPOUNDS OF THE FOLLOWING FORMULA:
Claim 3
Dependent Claim
76 words
The process according to claim 1 wherein said catalyst consists essentially of, based on the catalyst weight (a) 15-99% by weight, calculated as Fe2O3, of said iron oxide, (b) 1-85% by weight of said alkali metal compound and (c) up to 30% by weight of a compound selected from the group consisting of oxides, hydroxides, carbonates, bicarbonates, phosphates, borates, acetates, chromates and bichromates of Be, Mg, Ca, Sr and Ba and oxides of chromium or aluminum.
Claim 4
Dependent Claim
20 words
The process according to claim 1 wherein said reaction is carried out at a temperature ranginG between 500* and 750*C.
Claim 5
Dependent Claim
27 words
The process according to claim 1 wherein the liquid hourly space velocity of said compound of formula (1) to the catalyst is 0.05 - 5 hr 1.
Claim 6
Dependent Claim
27 words
The process according to claim 1 wherein said steam is used in an amount of 1 - 70 mols per mol of the compound of formula (1).
Claim 7
Dependent Claim
59 words
The process according to claim 1 wherein said catalyst consists essentially of, based on the catalyst weight, (a) 45-95% by weight, calculated as Fe2O3, of said iron oxide, (b) 5-55% by weight of said alkali metal compound and (c) up to 30% by weight of a compound selected from the group consisting of the oxides of chromium or aluminum.
Claim 8
Dependent Claim
42 words
The process according to claim 1 wherein said alkali metal compound is selected from the group consisting of the oxides, hydroxides, carbonates, bicarbonates, phosphates, borates, acetates, chromates and bichromates of a metal selected from the group consisting of Li, Na, or K.
References Cited (Backward Citations)
US2409676A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |