US4072584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrochemical production of organic thiols
Assignee: Honeywell International Inc
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Filing: 1976-12-21
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Granted: 1978-02-07
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Expires: 1996-12-21
Abstract
Abstract A process is described for the electrochemical reduction of organic disulfides in the presence of halide ion to form the corresponding thiols, which comprises using a stable solid cathode selected from the group consisting of the disulfides and diselenides of titanium, vanadium, molybdenum, tantalum, tungsten, niobium and zirconium, wherein the cathode does not undergo substantial disintegration during the reduction.
Inventors
- 👤 Divna Cipris
- 👤 Dirk Pouli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:34
CPC Classifications
C; C25; C25B; C25B3/00; C25B3/20; C25B3/25; C25B3/01; C25B3/11
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
89 words
A process for the electrochemical reduction of an organic disulfide, free from other reducible groups in the process, to the corresponding thiol in the presence of halide ion which comprises passing a direct electric current between (1) a stable solid cathode selected from the group consisting of the disulfides and diselenides of titanium, vanadium, molybdenum, tantalum, tungsten, niobium and zirconium, immersed in a catholyte containing the organic disulfide and halide ion, and (2) an anode immersed in an anolyte, wherein the anolyte and catholyte are separated by a membrane.
Claim 2
Dependent Claim
89 words
A process for the electrochemical reduction of an organic disulfide, free from other reducible groups in the process, to the corresponding thiol in the presence of halide ion which comprises passing a direct electric current between (1) a stable solid cathode selected from the group consisting of the disulfides and diselenides of titanium, vanadium, molybdenum, tantalum, tungsten, niobium and zirconium, immersed in a catholyte containing the organic disulfide and halide ion, and (2) an anode immersed in an anolyte, wherein the anolyte and catholyte are separated by a membrane.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the cathode is selected from the group consisting of the disulfides of titanium, vanadium, molybdenum, tantalum, tungsten, niobium and zirconium.
Claim 4
Dependent Claim
14 words
The process of claim 2 wherein the cathode is molybdenum disulfide or tungsten disulfide.
Claim 5
Dependent Claim
11 words
The process of claim 3 wherein the cathods is molybdenum disulfide.
Claim 6
Dependent Claim
23 words
The process of claim 1 wherein the organic disulfide is formed in situ by starting with a catholyte containing an organic sulfonyl halide.
Claim 7
Dependent Claim
20 words
The process of claim 5 wherein the sulfonyl halide is an organic sulfonyl chloride containing 1 to 20 carbon atoms.
Claim 8
Dependent Claim
13 words
The process of claim 6 wherein the organic sulfonyl chloride is 2,5-dichlorobenzenesulfonyl chloride.
Claim 9
Dependent Claim
15 words
The process of claim 1 wherein the organic disulfide contains 2 to 40 carbon atoms.
Claim 10
Dependent Claim
12 words
The process of claim 8 wherein the organic disulfide is 2,5-dichlorobenzene disulfide.
Claim 11
Dependent Claim
31 words
The process of claim 1 wherein said catholyte further contains an inert organic solvent which is a C 1 to C 8 monoaliphatic alcohol, dimethylformamide, dimethylacetamide, N-methyl-pyrrolidone, hexamethylphosphoramide, tri-n-butylphosphite or tetramethylenesulfone.
Claim 12
Dependent Claim
12 words
The process of claim 10 wherein the inert organic solvent is tetramethylenesulfone.
Claim 13
Dependent Claim
19 words
The process of claim 1 wherein said catholyte further contains an electrolyte to increase the conductivity of the catholyte.
Claim 14
Dependent Claim
11 words
The process of claim 12 wherein said electrolyte is hydrochloric acid.
Claim 15
Dependent Claim
29 words
The process of claim 1 wherein the cathode current density is about 5 to 500 mA/cm 2 and the temperature of the catholyte is about 20° to 250° C.
Claim 16
Dependent Claim
13 words
The process of claim 1 wherein said membrane is a cation exchange membrane.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-06 | 1981-08-08 | 1982-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-06 | 1985-08-08 | 1986-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-06 | 1989-08-08 | 1990-02-07 | $7700.00 | Window Closed / Lapsed |