US4491670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalytic process for the direct carbonylation of organic nitro compounds
Assignee: Indian Explosives Ltd
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Filing: 1983-01-27
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Granted: 1985-01-01
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Expires: 2003-01-27
Abstract
Abstract Isocyanates, or derivatives thereof, are produced from nitrobenzene or 2,4-dinitrotoluene by reaction with carbon monoxide in the presence of an iron, ruthenium, rhodium, or platinum carbonyl as catalyst.
Inventors
- 👤 Sumit Bhaduri
- 👤 Krishna R. Sharma
- 👤 Gopalkrishnan S. Kalpathi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:59
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/18; C07C273/1809; C07C263/00; C07C263/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
159 words
A process for the preparation of isocyanates or derivatives thereof which comprises reacting nitrobenzene or 2,4 dinitrotoluene with carbon monoxide or a mixture of carbon monoxide and inert gas in the presence of a polynuclear metal carbonyl or its derivative as catalyst designated by the formula M x (CO) y L z n- , wherein, ______________________________________
M = Fe x = 3 y = 12 z = 0 n = 0
Fe x = 3 y = 11 z = 1 L = H n = 1
Ru x = 3 y = 12 z = 0 n = 0
Ru x = 3 y = 11 z = 1 L = H n = 1
Ru x = 4 y = 12 z = 4 L = H n = 0
Rh x = 6 y = 16 z = 0 n = 0
Pt x = 15 y = 30 z = 0 n = 2.
______________________________________
Claim 2
Dependent Claim
159 words
A process for the preparation of isocyanates or derivatives thereof which comprises reacting nitrobenzene or 2,4 dinitrotoluene with carbon monoxide or a mixture of carbon monoxide and inert gas in the presence of a polynuclear metal carbonyl or its derivative as catalyst designated by the formula M x (CO) y L z n- , wherein, ______________________________________
M = Fe x = 3 y = 12 z = 0 n = 0
Fe x = 3 y = 11 z = 1 L = H n = 1
Ru x = 3 y = 12 z = 0 n = 0
Ru x = 3 y = 11 z = 1 L = H n = 1
Ru x = 4 y = 12 z = 4 L = H n = 0
Rh x = 6 y = 16 z = 0 n = 0
Pt x = 15 y = 30 z = 0 n = 2.
______________________________________
Claim 3
Dependent Claim
22 words
A process as claimed in claim 1 wherein the reaction is conducted at a temperature of from 30° C. to 200° C.
Claim 4
Dependent Claim
22 words
A process as claimed in claim 1 wherein the reaction is conducted at a pressure of from 1 atmosphere to 5000 p.s.i.
Claim 5
Dependent Claim
38 words
A process as claimed in claim 3 wherein the reaction is conducted in the presence of alcohols such as methanol, ethanol, propanol, isopropanol or butanol as solvents and reactants for the isocyanate products to give the urethane derivatives.
Claim 6
Dependent Claim
28 words
A process as claimed in claim 4 wherein the reaction is conducted in the presence of an inert liquid diluent such as tetrahydrofuran, acetonitrile, diglyene, benzene or toluene.
Claim 7
Dependent Claim
19 words
A process as claimed in claim 5 wherein ruthenium trichloride trihydrate is the precursor of the triruthenium dodeca carbonyl.
Claim 8
Dependent Claim
21 words
A process as claimed in claim 1 wherein the product isocyanate is converted to aniline by water present in the solvent.
Claim 9
Dependent Claim
15 words
A process as claimed in claim 1 wherein the inert gas is nitrogen or argon.
References Cited (Backward Citations)
US3923850A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-01 | 1988-07-02 | 1989-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-01 | 1992-07-02 | 1993-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-01 | 1996-07-02 | 1997-01-01 | $7700.00 | Window Closed / Lapsed |