US5196599A
Expired / Lapsed
US
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Method of preparing fluoro, nitro, and fluoronitroalkyl difluoroformals
Assignee: United States Department of the Navy
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Filing: 1981-03-30
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Granted: 1993-03-23
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Expires: 2001-03-30
Abstract
Abstract A method of preparing difluoroformals of the formula (RCH.sub.2 O).sub.2 CF.sub.2, wherein R is --C(NO 2 ) 3 , --CF(NO 2 ) 2 , --CF 2 (NO.su), --C(NO 2 ) 2 CH 3 , or a fluoroalkyl group such as --CF 3 or --CF 2 CF 3 , by reacting the corresponding dichloroformals with hydrogen fluoride in pyridine. These difluoroformals are useful as energetic explosive and propellant ingredients.
Inventors
- 👤 William H. Gilligan
- 👤 Michael E. Sitzmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:48
CPC Classifications
C; C07; C07C; C07C41/00; C07C41/48; C07C201/00; C07C201/06; C07C201/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
98 words
A method of preparing a difluoroformal of the formula (RCH.sub.2 O ).sub.2 CF.sub.2, wherein R is selected from the group consisting of --C(NO 2 ) 3 , --CF(NO 2 ) 2 , --CF 2 (NO 2 ), --C(NO 2 ) 2 CH 3 , --CF 3 , and --CF 2 CF 3 , comprising: (1) adding a dichloroformal of the formula (RCH.sub.2 O).sub.2 CCl.sub.2, wherein R is as defined above, to a solution of hydrogen fluoride in pyridine and allowing the dichloroformal to react with the hydrogen fluoride to give the difluoroformal; and (2) isolating the product difluoroformal.
Claim 2
Independent Claim
98 words
A method of preparing a difluoroformal of the formula (RCH.sub.2 O ).sub.2 CF.sub.2, wherein R is selected from the group consisting of --C(NO 2 ) 3 , --CF(NO 2 ) 2 , --CF 2 (NO 2 ), --C(NO 2 ) 2 CH 3 , --CF 3 , and --CF 2 CF 3 , comprising: (1) adding a dichloroformal of the formula (RCH.sub.2 O).sub.2 CCl.sub.2, wherein R is as defined above, to a solution of hydrogen fluoride in pyridine and allowing the dichloroformal to react with the hydrogen fluoride to give the difluoroformal; and (2) isolating the product difluoroformal.
Claim 3
Dependent Claim
40 words
The method of claim 1 wherein R is selected from the group consisting of --C(NO 2 ) 3 , --CF(NO 2 ) 2 , --CF 2 (NO 2 ), --C(NO 2 ) 2 CH 3 , and --CF 3 .
Claim 4
Dependent Claim
29 words
The method of claim 1 or 2 wherein the solution of hydrogen fluoride in pyridine comprises from about 60 to about 70 weight percent of hydrogen fluoride in pyridine.
References Cited (Backward Citations)
US3922311A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-03-22 | 1996-09-21 | 1997-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-22 | 2000-09-21 | 2001-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-22 | 2004-09-21 | 2005-03-23 | $7700.00 | Window Closed / Lapsed |