US4127575A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of chloro substituted pyridines
Assignee: Dow Chemical Co
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Filing: 1977-06-20
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Granted: 1978-11-28
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Expires: 1997-06-20
Abstract
Abstract In the process for preparing 2,3,5-trichloropyridine, 2,3,4,5- or 2,3,5,6-tetrachloropyridine by the oxidation of the appropriate trichloro- or tetrachlorohydrazinopyridine, the improvement which comprises carrying out the oxidation with an alkaline hypochlorite in the presence of a reaction medium.
Inventors
- 👤 Stanley D. McGregor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:37
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/72; C07D213/76; C07D213/77; C07D213/61
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
55 words
A method for preparing a member selected from the group of 2,3,5-trichloropyridine, 2,3,4,5-tetrachloropyridine and 2,3,5,6-tetrachloropyridine which comprises reacting an appropriate trichloro- or tetrachlorohydrazinopyridine reactant with an alkaline hypochlorite in the presence of a reaction medium at temperatures of from about room temperature to the boiling point of the reaction mixture and recovering the desired product.
Claim 2
Independent Claim
55 words
A method for preparing a member selected from the group of 2,3,5-trichloropyridine, 2,3,4,5-tetrachloropyridine and 2,3,5,6-tetrachloropyridine which comprises reacting an appropriate trichloro- or tetrachlorohydrazinopyridine reactant with an alkaline hypochlorite in the presence of a reaction medium at temperatures of from about room temperature to the boiling point of the reaction mixture and recovering the desired product.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the pyridine reactant is tetrachloro-4-hydrazinopyridine and the product is 2,3,5,6-tetrachloropyridine.
Claim 4
Dependent Claim
12 words
The process of claim 2 wherein the alkaline hypochlorite is sodium hypochlorite.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein the pyridine reactant is tetrachloro-2-hydrazinopyridine and the product is 2,3,4,5-tetrachloropyridine.
Claim 6
Dependent Claim
12 words
The process of claim 4 wherein the alkaline hypochlorite is sodium hypochlorite.
Claim 7
Dependent Claim
27 words
The process of claim 1 wherein the pyridine reactant is a mixed feed of tetrachloro-2-hydrazinopyridine and tetrachloro-4-hydrazinopyridine and the product is a mixture of 2,3,4,5-tetrachloropyridine and 2,3,5,6-tetrachloropyridine.
Claim 8
Dependent Claim
12 words
The process of claim 6 wherein the alkaline hypochlorite is sodium hypochlorite.
Claim 9
Dependent Claim
16 words
The process of claim 1 wherein the pyridine reactant is 2,3,5-trichloro-6-hydrazinopyridine and the product is 2,3,5-trichloropyridine.
Claim 10
Dependent Claim
12 words
The process of claim 8 wherein the alkaline hypochlorite is sodium hypochlorite.
Claim 11
Independent Claim
46 words
A method for preparing 2,3,5-trichloropyridine which comprises reacting a mixture of 2,3,5-trichloro-6-hydrazinopyridine and 2,3,5-trichloro-4-hydrazinopyridine with an alkaline hypochlorite in the presence of a reaction medium at temperatures of from about room temperature to the boiling point of the reaction mixture and recovering the desired 2,3,5-trichloropyridine product.
Claim 12
Independent Claim
46 words
A method for preparing 2,3,5-trichloropyridine which comprises reacting a mixture of 2,3,5-trichloro-6-hydrazinopyridine and 2,3,5-trichloro-4-hydrazinopyridine with an alkaline hypochlorite in the presence of a reaction medium at temperatures of from about room temperature to the boiling point of the reaction mixture and recovering the desired 2,3,5-trichloropyridine product.
Claim 13
Dependent Claim
12 words
The process of claim 10 wherein the alkaline hypochlorite is sodium hypochlorite.
References Cited (Backward Citations)
US3927003A
Cited
US3947457A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-11-27 | 1982-05-29 | 1982-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-27 | 1986-05-29 | 1986-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-27 | 1990-05-29 | 1990-11-28 | $7700.00 | Window Closed / Lapsed |