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US4092363A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of dialkylphosphine oxides

Assignee: Hoechst AG
•
Filing: 1976-09-30
•
Granted: 1978-05-30
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Expires: 1996-09-30
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Abstract

Abstract Production of dialkylphosphine oxides of the general formula: ##STR1## in which R 1 and R 2 each stand for an alkyl group having from 1 to 4 carbon atoms by subjecting a dialkylchlorophosphine of the general formula: ##STR2## in which R 1 and R 2 have the meanings given above, or an addition product thereof with hydrogen chloride, to alcoholysis with an aliphatic C 1 - C 4 alcohol in the presence of a protective gas at temperatures between -30° and +30° C, and subjecting the resulting alcoholysate to thermolysis. The compounds are more specifically produced by continuously adding the dialkylchlorophosphine component to the alcohol; subjecting the resulting alcoholysate to thermolysis in a heated separation zone; introducing into the separation zone, countercurrently to the alcoholysate, 10 to 150 l/h of a protective gas, per liter of alcoholysate; removing simultaneously from the separation zone the gaseous thermolysis products and, separately from said products, an alcoholic solutions containing desirable final product; neutralizing the alcoholic solution and recovering the final product from said solution in known manner.

Inventors

  • 👤 Horst Staendeke
  • 👤 Hubert Neumaier

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 05:21
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/46; C07F9/50; C07F9/53; C07F9/5304

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 173 words
In a process for making dialkylphosphine oxides of the general formula: ##STR6## in which R 1 and R 2 each stand for an alkyl group having from 1 to 4 carbon atoms by subjecting a dialkylchlorophosphine of the general formula: ##STR7## in which R 1 and R 2 have the meanings given above, an addition product thereof with hydrogen chloride or mixture thereof, to alcoholysis with an aliphatic C 1 - C 4 alcohol in the presence of a protective gas at temperatures between -30° and +30° C, and subjecting the resulting alcoholysate to thermolysis, the improvement which comprises: continuously adding the dialkylchlorophosphine component to the alcohol; subjecting the resulting alcoholysate to thermolysis in a heated separation zone; introducing into the separation zone, countercurrently to the alcoholysate, 10 to 150 l/h of a protective gas, per liter of alcoholysate; removing simultaneously from the separation zone the gaseous thermolysis products and, separately from said products, an alcoholic solution containing desirable final product; neutralizing the alcoholic solution and recovering the final product from said solution.
Claim 2
Dependent Claim 173 words
In a process for making dialkylphosphine oxides of the general formula: ##STR6## in which R 1 and R 2 each stand for an alkyl group having from 1 to 4 carbon atoms by subjecting a dialkylchlorophosphine of the general formula: ##STR7## in which R 1 and R 2 have the meanings given above, an addition product thereof with hydrogen chloride or mixture thereof, to alcoholysis with an aliphatic C 1 - C 4 alcohol in the presence of a protective gas at temperatures between -30° and +30° C, and subjecting the resulting alcoholysate to thermolysis, the improvement which comprises: continuously adding the dialkylchlorophosphine component to the alcohol; subjecting the resulting alcoholysate to thermolysis in a heated separation zone; introducing into the separation zone, countercurrently to the alcoholysate, 10 to 150 l/h of a protective gas, per liter of alcoholysate; removing simultaneously from the separation zone the gaseous thermolysis products and, separately from said products, an alcoholic solution containing desirable final product; neutralizing the alcoholic solution and recovering the final product from said solution.
Claim 3
Dependent Claim 21 words
The process as claimed in claim 1, wherein the alcoholysate is subjected to thermolysis at temperatures of 60° to 120° C.
Claim 4
Dependent Claim 17 words
The process as claimed in claim 2, wherein the thermolysis is effected at 80° to 100° C.
Claim 5
Dependent Claim 23 words
The process as claimed in claim 1, wherein nitrogen or hydrogen chloride or both are introduced into the separating zone as protective gas.
Claim 6
Dependent Claim 27 words
The process as claimed in claim 1, wherein 10 to 60 l per hour of protective gas is introduced, per liter of alcoholysate, into the separating zone.
Claim 7
Dependent Claim 44 words
The process as claimed in claim 1, wherein the reaction heat set free on effecting the alcoholysis is dissipated by conveying the alcoholysate through at least one heat exchanger zone and the alcoholysate leaving the heat exchanger zone is introduced into the separating zone.
Claim 8
Dependent Claim 44 words
The process as claimed in claim 1, wherein the dialkylchlorophosphine, an addition product thereof with hydrogen chloride or mixture thereof is the crude product produced by the process comprising reacting vaporous phosphorus with an alkyl chloride in the presence of active carbon as catalyst.

References Cited (Backward Citations)

US3126416A Cited
DE1568928A1 Cited
DE1952605A1 Cited
US3855311A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-05-29 1981-11-28 1982-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-05-29 1985-11-28 1986-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-05-29 1989-11-28 1990-05-30 $7700.00 Window Closed / Lapsed

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