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Preparation of carboxylic acid anhydrides

Assignee: Halcon Research and Development Corp
•
Filing: 1975-12-22
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Granted: 1977-01-11
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Expires: 1995-12-22
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Abstract

Abstract A carboxylic acid anhydride, such as acetic anhydride, is prepared from a carboxylate ester or a hydrocarbyl ether in carbonylation processes comprising the use of an iodide, carbon monoxide and a nickel-chromium catalyst in the presence of a promoter comprising an organo-nitrogen compound or an organo-phosphorus compound wherein the nitrogen and phosphorus are trivalent.

Inventors

  • 👤 Anthony N. Naglieri
  • 👤 Nabil Rizkalla

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 17:38
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/54; C07C51/56

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 76 words
A process for the preparation of an anhydride of a mono-carboxylic acid which comprises reacting carbon monoxide and an alkyl or aryl carboxylic acid ester or an alkyl or aryl ether under substantially anhydrous conditions at elevated temperature and super atmospheric pressure in the presence of a halide which is an iodide or a bromide and a catalyst comprising nickel and chromium in the presence of a promoter comprising an organo-trivalent nitrogen compound or a phosphine.
Claim 2
Dependent Claim 76 words
A process for the preparation of an anhydride of a mono-carboxylic acid which comprises reacting carbon monoxide and an alkyl or aryl carboxylic acid ester or an alkyl or aryl ether under substantially anhydrous conditions at elevated temperature and super atmospheric pressure in the presence of a halide which is an iodide or a bromide and a catalyst comprising nickel and chromium in the presence of a promoter comprising an organo-trivalent nitrogen compound or a phosphine.
Claim 3
Dependent Claim 33 words
A process as defined in claim 1, wherein the anhydride is a lower alkanoic anhydride, the carboxylic acid ester is a lower alkyl lower alkanoate and the ether is a lower alkyl ether.
Claim 4
Dependent Claim 15 words
A process as defined in claim 1, wherein the promoter is an organo-trivalent nitrogen compound.
Claim 5
Dependent Claim 13 words
A process as defined in claim 1, wherein the promoter is a phosphine.
Claim 6
Dependent Claim 26 words
A process as defined in claim 1, wherein the anhydride is acetic anhydride, the carboxylic acid ester is methyl acetate and the ether is dimethyl ether.
Claim 7
Dependent Claim 23 words
A process as defined in claim 1, wherein the reaction is carried out under a carbon monoxide partial pressure up to 1000 psi.

References Cited (Backward Citations)

US2497304A Cited
US2593440A Cited
US2739169A Cited
US2607787A Cited
US2730546A Cited
US2789137A Cited
US3641074A Cited
US3641071A Cited
US3927078A Cited
US3852346A Cited
US3887595A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-01-11 1980-07-12 1981-01-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-01-11 1984-07-12 1985-01-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-01-11 1988-07-12 1989-01-11 $7700.00 Window Closed / Lapsed

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