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US5166423A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the oxidation of alcohols to acids

Assignee: Shell USA Inc
•
Filing: 1991-08-30
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Granted: 1992-11-24
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Expires: 2011-08-30
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Abstract

Abstract A process for the preparation of an alkanoic acid which comprises reacting the corresponding alkanol with a solubilized stable free radical nitroxide having the formula: ##STR1## wherein each of R 1 , R 2 , R 3 and R 4 is an alkyl, aryl or heteroatom substituted alkyl group having 1 to about 15 carbon atoms and each of R 5 and R 6 is alkyl, hydrogen, aryl or a substituted heteroatom, and nitric acid in the presence of an oxidant at a temperature in the range of from about 25° C. to about 65° C. and thereafter separating out the alkanoic acid.

Inventors

  • 👤 Herbert E. Fried

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 00:06
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/27

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 103 words
A process for the preparation of an alkanoic acid which comprises reacting the corresponding alkanol with a solubilized stable free radical nitroxide having the formula: ##STR5## wherein each of R 1 , R 2 , R 3 and R 4 is an alkyl, aryl or heteroatom substituted alkyl group having 1 to about 15 carbon atoms and each of R 5 and R 6 is alkyl, hydrogen, aryl or a substituted heteroatom, and nitric acid in the presence of an oxidant at a temperature in the range of from about 25° C. to about 65° C. and thereafter separating out the alkanoic acid.
Claim 2
Dependent Claim 103 words
A process for the preparation of an alkanoic acid which comprises reacting the corresponding alkanol with a solubilized stable free radical nitroxide having the formula: ##STR5## wherein each of R 1 , R 2 , R 3 and R 4 is an alkyl, aryl or heteroatom substituted alkyl group having 1 to about 15 carbon atoms and each of R 5 and R 6 is alkyl, hydrogen, aryl or a substituted heteroatom, and nitric acid in the presence of an oxidant at a temperature in the range of from about 25° C. to about 65° C. and thereafter separating out the alkanoic acid.
Claim 3
Dependent Claim 27 words
The process of claim 1 wherein the solubilized stable free radical nitroxide is selected from the group consisting of 2,2,6,6-tetramethyl-piperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethyl-piperidine-1-oxyl, 4-alkoxy-2,2,6,6-tetramethyl-piperidine-1-oxyl, 4-oxo-2,2,6,6-tetramethyl-piperidine-1-oxyl, 2,2,6,6-tetramethyl-piperidine-1-oxyl-4-sulfate, and mixtures thereof.
Claim 4
Dependent Claim 25 words
The process of claim 2 wherein the solubilized stable free radical nitroxide is selected from the group consisting of 2,2,6,6-tetramethyl-piperidine-1-oxyl, 2,2,6,6-tetramethyl-piperidine-1-oxyl-4-sulfate, 4-alkoxy-2,2,6,6-tetramethyl-piperidine-1-oxyl and mixtures thereof.
Claim 5
Dependent Claim 34 words
The process of claim 1 wherein the stable free radical nitroxide is dissolved in a solvent selected from the group consisting of acetonitrile, tertiary butyl alcohol, tertiary amyl alcohol, ethyl acetate and mixtures thereof.
Claim 6
Dependent Claim 29 words
The process of claim 4 wherein the stable free radical nitroxide is dissolved in a solvent selected from the group consisting of tertiary butyl alcohol acetonitrile, and mixtures thereof.
Claim 7
Dependent Claim 24 words
The process of claim 1 wherein said nitric acid has a concentration in the range of from about 50 percent to about 100 percent.
Claim 8
Dependent Claim 16 words
The process of claim 6 wherein said nitric acid has a concentration of about 70 percent.
Claim 9
Dependent Claim 29 words
The process of claim 1 wherein said alkanol is contacted with said solubilized stable free radical nitroxide, followed by the addition thereto of said nitric acid and said oxidant.
Claim 10
Dependent Claim 37 words
The process of claim 8 wherein the amount of solubilized stable free radical nitroxide is in the range of from about 1 mole percent to about 50 mole percent, basis the number of moles of starting alkanol.
Claim 11
Dependent Claim 37 words
The process of claim 8 wherein the amount of solubilized stable free radical nitroxide is in the range of from about 5 mole percent to about 30 mole percent basis the number of moles of starting alkanol.
Claim 12
Dependent Claim 34 words
The process of claim 8 wherein the amount of nitric acid is in the range of from about 5 mole percent to about 100 mole percent, basis the number of moles of starting alkanol.
Claim 13
Dependent Claim 12 words
The process of claim 1 wherein said oxidant is an oxygen-containing gas.
Claim 14
Dependent Claim 20 words
The process of claim 12 wherein said oxygen-containing gas is selected from the group consisting of pure oxygen and air.
Claim 15
Dependent Claim 12 words
The process of claim 13 wherein said oxygen-containing gas is pure oxygen.
Claim 16
Dependent Claim 30 words
The process of claim 1 wherein said process is carried out at a temperature in the range of from about 30° C. to about 45° C. and at atmospheric pressure.
Claim 17
Dependent Claim 30 words
The process of claim 15 wherein said process is carried out at a temperature in the range of from about 35° C. to about 40° C. and at atmospheric pressure.

References Cited (Backward Citations)

US4620033A Cited
JPH0596516A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-11-24 1996-05-25 1996-11-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-11-24 2000-05-25 2000-11-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-11-24 2004-05-25 2004-11-24 $7700.00 Window Closed / Lapsed

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