US4370501A
Expired / Lapsed
US
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Synthesis of bis(aminophenyl) compounds
Assignee: Raytheon Co
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Filing: 1981-10-05
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Granted: 1983-01-25
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Expires: 2001-10-05
Abstract
Abstract A simplified process for converting bis-phenols to dianilines is disclosed. Selected catalytic complexes are used to cause a nucleophilic displacement reaction between a bis-phenol and a quinazoline to occur thereby yielding a bis-quinazoline that may be subsequently converted into a bis-quinazolinone and hydrolyzed to form the desired dianiline.
Inventors
- 👤 Kreisler S. Y. Lau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:18
CPC Classifications
C; C07; C07D; C07D239/00; C07D239/70; C07D239/72; C07D239/86; C07D239/88; C07D239/91
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
88 words
A process for conversion of bisphenols to dianilines comprising the steps of: a. forming the reaction product of an anhydrous bis-phenol and a halogenated phenyl-quinazoline by heating said compounds in the presence of a crown ether catalyst, a strong base, and a high-boiling polar solvent; b. subjecting said product to a thermal rearrangement by heating it in an inert atmosphere to thereby form a bis-quinazolinone; and c. hydrolyzing said bis-quinazolinone by refluxing it in the presence of a strong base in an alcoholic solvent, thereby forming a dianiline.
Claim 2
Dependent Claim
88 words
A process for conversion of bisphenols to dianilines comprising the steps of: a. forming the reaction product of an anhydrous bis-phenol and a halogenated phenyl-quinazoline by heating said compounds in the presence of a crown ether catalyst, a strong base, and a high-boiling polar solvent; b. subjecting said product to a thermal rearrangement by heating it in an inert atmosphere to thereby form a bis-quinazolinone; and c. hydrolyzing said bis-quinazolinone by refluxing it in the presence of a strong base in an alcoholic solvent, thereby forming a dianiline.
Claim 3
Dependent Claim
44 words
The process of claim 1 wherein said bis-phenol is a bis-phenol selected from the group whose formula is: ##STR4## where X is a single bond, S, O, SO 2 , CO, or C(CF n H 3-n ) where n is 0, 1 or 2.
Claim 4
Dependent Claim
25 words
A process in accordance with claim 1 wherein said halogenated phenylquinazoline is a compound whose structure is ##STR5## where X is Cl, Br or I.
Claim 5
Dependent Claim
27 words
The process of claim 1 or of claim 2 wherein said bis-phenol and said phenylquinazoline is heated in the presence of an 18-Crown-6 catalyst and potassium hydroxide.
Claim 6
Dependent Claim
14 words
The process of claim 2 wherein X in said bis-phenol contains a hexafluoroisopropylidene substituent.
Claim 7
Dependent Claim
104 words
An improved process for synthesizing 2,2-bis-(4-aminophenyl)hexafluoropropane comprising the steps of: heating a solution of 2,2-bis(4-hydroxyphenyl)hexafluoropropane with 4-chloro-2-phenylquinazoline in the presence of a catalytic mixture formed from a crown ether catalyst and a strong base in a high-boiling polar solvent, thereby causing a nucleophilic displacement reaction to occur which yields a bisquinazoline; heating said bis-quinazoline under an inert atmospheric purge thereby causing a thermal rearrangement to occur yielding a bisquinazolinone; and subsequently hydrolyzing said bisquinazoline by refluxing it in an alcoholic solvent with a strong base to form said bis(aminophenyl)hexafluoropropane which may be subsequently extracted from said alcoholic solvent and purified to a crystalline solid.
Claim 8
Dependent Claim
104 words
An improved process for synthesizing 2,2-bis-(4-aminophenyl)hexafluoropropane comprising the steps of: heating a solution of 2,2-bis(4-hydroxyphenyl)hexafluoropropane with 4-chloro-2-phenylquinazoline in the presence of a catalytic mixture formed from a crown ether catalyst and a strong base in a high-boiling polar solvent, thereby causing a nucleophilic displacement reaction to occur which yields a bisquinazoline; heating said bis-quinazoline under an inert atmospheric purge thereby causing a thermal rearrangement to occur yielding a bisquinazolinone; and subsequently hydrolyzing said bisquinazoline by refluxing it in an alcoholic solvent with a strong base to form said bis(aminophenyl)hexafluoropropane which may be subsequently extracted from said alcoholic solvent and purified to a crystalline solid.
Claim 9
Dependent Claim
25 words
The process of claim 6 wherein said catalytic mixture is formed from an 18-Crown-6 catalyst and potassium hydroxide and wherein said polar solvent is dimethylsulfoxide.
Claim 10
Dependent Claim
18 words
The process of claim 6 wherein said bisquinazoline is heated at 320°±5° C. for at least 15 hours.
References Cited (Backward Citations)
US3418371A
Cited
US4177211A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-24 | 1986-07-26 | 1987-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-24 | 1990-07-26 | 1991-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-24 | 1994-07-26 | 1995-01-25 | $7700.00 | Window Closed / Lapsed |