US4912210A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of (cyclo)aliphatic uretediones
Assignee: Evonik Operations GmbH
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Filing: 1988-09-15
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Granted: 1990-03-27
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Expires: 2008-09-15
Abstract
Abstract A process for the preparation of a uretedione, comprising the steps of: (i) reacting at least one C 6-15 (cyclo)aliphatic diisocyanate under substantially anhydrous conditions with a pyridine of the formula ##STR1## wherein R 1 and R 2 are, independent from one another, a C 1-4 alkyl group or R 1 and R 2 taken together with the attached nitrogen form a pyrrolidine, piperidine or morpholine ring, to form a reaction mixture containing said uretedione, and (ii) isolating said uretedione from said reaction mixture by vacuum thin layer evaporation after the degree of dimerization in said reaction mixture has reached 10-80%.
Inventors
- 👤 Josef Disteldorf
- 👤 Werner Huebel
- 👤 Karl Schmitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:38
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/79; C08G18/798; C07; C07D; C07D229/00
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
117 words
A process for the preparation of a uretedione, consisting essentially of the steps of: (i) reacting a C 6-15 (cyclo)aliphatic diisocyanate under substantially anhydrous conditions with a pyridine of the formula wherein said pyridine is used in a quantity ranging from 0.05-10% by weight relate to the diisocyanate wherein R 1 and R 2 are, independently from one another, a C 1-4 alkyl group or R 1 and R 2 taken together with the attached nitrogen form a pyrrolidine, piperidine or morpholine ring, to form a reaction mixture containing said uretedione, and (ii) isolating said uretedione from said reaction mixture by vacuum thin layer evaporation after the degree of dimerization in said reaction mixture has reached 10-80%.
Claim 2
Dependent Claim
117 words
A process for the preparation of a uretedione, consisting essentially of the steps of: (i) reacting a C 6-15 (cyclo)aliphatic diisocyanate under substantially anhydrous conditions with a pyridine of the formula wherein said pyridine is used in a quantity ranging from 0.05-10% by weight relate to the diisocyanate wherein R 1 and R 2 are, independently from one another, a C 1-4 alkyl group or R 1 and R 2 taken together with the attached nitrogen form a pyrrolidine, piperidine or morpholine ring, to form a reaction mixture containing said uretedione, and (ii) isolating said uretedione from said reaction mixture by vacuum thin layer evaporation after the degree of dimerization in said reaction mixture has reached 10-80%.
Claim 3
Dependent Claim
18 words
The process of claim 1, wherein said uretedione isolated from said reaction mixture is more than 99% pure.
Claim 4
Dependent Claim
23 words
The process of claim 1, wherein said isolating step is conducted after the degree of dimerization in said reaction mixture has reached 20-60%.
Claim 5
Dependent Claim
14 words
The process of claim 1, wherein 0.2-5% by weight of said pyridine is used.
Claim 6
Dependent Claim
19 words
The process of claim 1, wherein R 1 and R 2 , independently, are a methyl or ethyl group.
Claim 7
Dependent Claim
18 words
The process of claim 1, wherein said reacting step is conducted at a temperature from about 0°-100° C.
Claim 8
Dependent Claim
18 words
The process of claim 6, wherein said reacting step is conducted at a temperature from about 20°-80° C.
Claim 9
Dependent Claim
32 words
The process of claim 1, wherein said vacuum thin layer evaporation is performed at a vacuum ranging from about 0.1 to 20 mbar and at a temperature ranging from about 150°-190° C.
Claim 10
Dependent Claim
31 words
The process of claim 1, wherein the distillate obtained by said vacuum thin layer evaporation comprises said diisocyanate and said pyridine and wherein said distillate is recycled to said reacting step.
Claim 11
Dependent Claim
15 words
The process of claim 1, wherein said reacting step is conducted in inert gas atmosphere.
Claim 12
Dependent Claim
14 words
The process of claim 1, wherein said diisocyanate is a C 8-12 (cyclo)aliphatic diisocyanate.
Claim 13
Dependent Claim
29 words
The process of claim 1, wherein said diisocyanate is selected from the group consisting of hexamethylene diisocyanate, dodecamethylene diisocyanate, bis(4-isocyanatocyclohexyl)-methane, 2-methylpentamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate and isophorone diisocyanate.
Claim 14
Dependent Claim
11 words
The process of claim 1, wherein said diisocyanate is isophorone diisocyanate.
Claim 15
Dependent Claim
18 words
The process of claim 1, wherein said reacting step is conducted in the presence of an inert solvent.
References Cited (Backward Citations)
GB1207673A
Cited
DE3420113A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-26 | 1993-09-25 | 1994-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-26 | 1997-09-25 | 1998-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-26 | 2001-09-25 | 2002-03-27 | $7700.00 | Window Closed / Lapsed |