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US4590285A
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US
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Process for preparing a mixture of tetrahydrofuran and 3-alkyl tetrahydrofuran and copolymers thereof
Assignee: EIDP Inc
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Filing: 1984-11-15
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Granted: 1986-05-20
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Expires: 2004-11-15
Abstract
Abstract A mixture of 1,4-butanediol and 2-alkyl-1,4-butanediol is produced by catalytic hydrogenation and reaction with an aldehyde. Such mixture is cyclized to a mixture of tetrahydrofuran and 3-alkyl tetrahydrofuran. Copolymers can then be made from such mixtures of furans.
Inventors
- 👤 Richard E. Ernst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:42
CPC Classifications
C; C07; C07C; C07C29/00; C07C29/17; C07C29/172; C07C29/32; C07D; C07D307/00; C07D307/02; C07D307/04; C07D307/06; C07D307/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
76 words
In the method of preparing tetrahydrofurans by cyclizing diols, the improvement comprising using a mixture of 1,4-butanediol and 2-alkyl-1,4-butanediol produced by bringing together, at an initial pH of 9-14, and a temperature and pressure suitable reaction, (a) hydrogen, (b) hydrogenation catalyst, and (c) 1,4-butynediol or 1,4-butenediol, and an aldehyde of the structure R--CHO where R is hydrogen or an alkyl radical of 1-4 carbon atoms, in a butynediol or butenediol/aldehyde weight ratio of 2/1 to 200/1.
Claim 2
Dependent Claim
76 words
In the method of preparing tetrahydrofurans by cyclizing diols, the improvement comprising using a mixture of 1,4-butanediol and 2-alkyl-1,4-butanediol produced by bringing together, at an initial pH of 9-14, and a temperature and pressure suitable reaction, (a) hydrogen, (b) hydrogenation catalyst, and (c) 1,4-butynediol or 1,4-butenediol, and an aldehyde of the structure R--CHO where R is hydrogen or an alkyl radical of 1-4 carbon atoms, in a butynediol or butenediol/aldehyde weight ratio of 2/1 to 200/1.
Claim 3
Dependent Claim
37 words
A method for preparing a copolymer of tetrahydrofuran and 3-alkyltetrahydrofuran, the method comprising adding a suitable polymerization catalyst to the mixture produced by the method of claim 1 and holding the mixture under conditions suitable for polymerization.
Claim 4
Dependent Claim
16 words
The method of claim 1 wherein the butynediol or butenediol/aldehyde weight ratio is 2/1 to 27/1.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the butynediol or butenediol/aldehyde weight ratio is 2/1 to 25/1.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein the butynediol or butenediol/aldyhyde weight ratio is 10/1 to 25/1.
Claim 7
Dependent Claim
10 words
The method of claim 3 wherein the aldehyde is formaldehyde.
Claim 8
Dependent Claim
10 words
The method of claim 6 wherein the pH is 10-11.
Claim 9
Dependent Claim
18 words
The method of claim 2 wherein the butynediol or butenediol/aldehyde weight ratio is 2/1 to 27 to 1.
Claim 10
Dependent Claim
16 words
The method of claim 2 wherein the butynediol or butenediol/aldehyde weight ratio is 2/1 to 25/1.
Claim 11
Dependent Claim
16 words
The method of claim 2 wherein the butynediol of butenediol/aldehyde weight ratio is 10/1 to 25/1.
Claim 12
Dependent Claim
10 words
The method of claim 8 wherein the aldehyde is formaldehyde.
Claim 13
Dependent Claim
10 words
The method of claim 11 wherein the pH is 10-11.
References Cited (Backward Citations)
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GB1242358A
Cited
US3859369A
Cited
US4120850A
Cited
US4197248A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |