US3833490A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of 3,5-diiodo-4-hydroxybenzonitrile or 3-iodo-4-hydroxy-5-nitro-benzonitrile
Assignee: Rhone Poulenc SA
•
Filing: 1973-02-23
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Granted: 1974-09-03
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Expires: 1993-02-23
Abstract
Abstract WHEREIN X represents hydrogen, iodine or nitro, and R represents hydrogen, an alkali metal atom or alkanoyl of 1 through 4 carbon atoms, in an electrolysis cell in which the anolyte contains an alkali metal iodide or iodine and a solution or suspension of a compound of said formula. The compounds 3,5-diiodo-4-hydroxy-benzonitrile and 3-iodo-4hydroxy-5-nitro-benzonitrile, which are known to possess herbicidal and chemotherapeutic properties respectively, are prepared by anodic iodination of a compound of the formula:
Inventors
- 👤 J Philipot
- 👤 J Bizot
- 👤 J Courteix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:24
CPC Classifications
C; C07; C07C; C07C255/00; C25; C25B; C25B3/00; C25B3/01; C25B3/07; C25B3/09; C25B3/11; C25B3/20; C25B3/27
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
10 words
Process according to claim 1 in which X represents hydrogen.
Claim 2
Dependent Claim
17 words
Process according to claim 1 in which the anode is platinum, platinised titanium, stainless steel or graphite.
Claim 3
Dependent Claim
47 words
Process according to claim 1 in which the anolyte comprises a solution or a suspension of a nitrile of formula (I) as defined in claim 1 in water or a mixture of water and acetonitrile or methanol, containing 10 to 30% by volume of acetonitrile or methanol.
Claim 4
Dependent Claim
33 words
Process according to claim 1 in which the initial constitution of the catholyte is the same as that of the anolyte, except that the catholyte does not contain the nitrile of formula (I).
Claim 5
Dependent Claim
23 words
Process according to claim 1 in which the electrolysis is carried out at a constant current density of between 0.1 and 10 A/dm2.
Claim 6
Dependent Claim
35 words
Process according to claim 1 in which the electrolysis is carried out at a controlled anode potential of between -0.15 and +1 volt relative to a reference electrode of mercurous sulphate saturated with potassium sulphate.
Claim 7
Dependent Claim
17 words
Process according to claim 1 in which the pH of the anolyte is between 5 and 9.
Claim 8
Dependent Claim
29 words
Process according to claim 1 in which, when X in the compound of formula (I) represents hydrogen or iodine, the iodination is carried out at pH 7 to 12.
Claim 9
Dependent Claim
33 words
Process according to claim 1 in which, when X in the compound of formula (I) represents nitro, R represents a hydrogen atom and the iodination is carried out at pH 4 to 7.
Claim 10
Dependent Claim
42 words
Process according to cLaim 1 in which the cathode is platinum or a metal of the platinum group of metals in the Periodic Table of Elements, used as the bulk metal or deposited on stainless steel, graphite, vitreous carbon, titanium or tantalum.
Claim 11
Dependent Claim
15 words
Process according to claim 1 in which the separating diaphragm is a cation exchange membrane.
Claim 12
Dependent Claim
21 words
Process according to claim 1 in which the anode, the cathode and the separating diaphragm are located in vertical parallel planes.
Claim 13
Dependent Claim
34 words
Process according to claim 1 in which the anode or cathode, or anode and cathode, compartments contain spacers and the apparent speed of the anolyte through the anode compartment is greater than 1 cm/second.
Claim 14
Dependent Claim
23 words
Process according to claim 1 in which the speed of flow of the anolyte through the anode compartment is greater than 10 cm/second.
Claim 15
Dependent Claim
46 words
Process according to claim 1 in which the anolyte is made to flow over the surface of the anode by circulating it in a closed circuit by removal of anolyte at one end of the anode compartment and re-injection at another end of this same compartment.
Claim 16
Dependent Claim
25 words
Process according to claim 1 in which the anolyte in the anode compartment is stirred to cause flow of the anolyte over the anode surface.
Claim 17
Dependent Claim
36 words
Process according to claim 16 in which the catholyte is also circulated and the pressure on either side of the diaphragm separating anolyte and catholyte is equilibrated by using similar circuits for the anolyte and catholyte.
References Cited (Backward Citations)
US3386899A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-02 | 1978-03-04 | 1978-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-02 | 1982-03-04 | 1982-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-02 | 1986-03-04 | 1986-09-03 | $7700.00 | Window Closed / Lapsed |