US4937000A
Expired / Lapsed
US
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Optically active (meth)acrylamides, a process for their preparation, and their use for racemate resolution
Assignee: Daicel Corp
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Filing: 1989-10-18
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Granted: 1990-06-26
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Expires: 2009-10-18
Abstract
Abstract The invention relates to optically active homo- and copolymers made from optically active (meth)acrylamides, the polymers being immobilized on silica gel, a process for their preparation, and their use as adsorbents, in particular as the stationary phase for chromatographic racemate resolution.
Inventors
- 👤 Bruno Bomer
- 👤 Rolf Grosser
- 👤 Ulrich Schwartz
- 👤 Dieter Arlt
- 👤 Karl-Erwin Piejko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:35
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/29; B01J20/286; B01J20/30; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3214; B01J20/3217; B01J20/3231; B01J20/3242; B01J20/3268; B01J20/327; B01J20/3276; B01J20/3278; C; C08; C08F; C08F20/00; C08F20/02; C08F20/52; C08F20/54; B01J2220/00; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
110 words
In the chromatographic resolution of a racemic mixture into its optical antipodes by contacting a solution of the mixture with an adsorbent, the improvement which comprises employing as the absorbent a silica gel-immobilized, optically active (co)polymer made from (A) 10-100% by weight of an optically active monomer unit of the formula ##STR9## in which R 1 is hydrogen or methyl, and R 2 is one of the stereoisomers of the eight possible stereoisomeric forms of each of the optically active radicals of the formulae ##STR10## and (B) 90-0% by weight of a monomer unit of the group comprising C 1 -C 8 -alkyl (meth)acrylates, styrene, acrylonitrile, (meth)acrylamide and nitrogen-substituted (meth)acrylamides.
Claim 2
Dependent Claim
110 words
In the chromatographic resolution of a racemic mixture into its optical antipodes by contacting a solution of the mixture with an adsorbent, the improvement which comprises employing as the absorbent a silica gel-immobilized, optically active (co)polymer made from (A) 10-100% by weight of an optically active monomer unit of the formula ##STR9## in which R 1 is hydrogen or methyl, and R 2 is one of the stereoisomers of the eight possible stereoisomeric forms of each of the optically active radicals of the formulae ##STR10## and (B) 90-0% by weight of a monomer unit of the group comprising C 1 -C 8 -alkyl (meth)acrylates, styrene, acrylonitrile, (meth)acrylamide and nitrogen-substituted (meth)acrylamides.
Claim 3
Dependent Claim
30 words
The process according to claim 1, in which the component A is present in an amount of 30-100% by weight and component B in an amount of 70-0% by weight.
Claim 4
Dependent Claim
46 words
The process according to claim 1, wherein a further monomer unit which can bond covalently to silica gel or carries a functional group which makes possible covalent linking to silica gel is present in an amount of 0.1-50 mol % relative to components A and B.
Claim 5
Dependent Claim
20 words
The process according to claim 3, where the further monomer unit is present in an amount of 0.5-25 mol %.
Claim 6
Dependent Claim
46 words
The process according to claim 1, wherein component A is a monomer of the stated formula in which R 1 is hydrogen or methyl, and R 2 is a stereoisomer of the eight possible stereoisomeric forms of the optically active radical of the structural formula ##STR11##
Claim 7
Dependent Claim
14 words
The process according to claim 1, wherein component A is 1-menthyl(meth)acrylamide, d-menthyl(meth)acrylamide or d-neomenthyl(meth)acrylamide.
Claim 8
Dependent Claim
15 words
The process according to claim 1, wherein the polymer is made exclusively from component A.
Claim 9
Dependent Claim
28 words
The process according to claim 1, wherein the amount of immobilized optically active (co)polymer is 0.2 to 100% by weight relative to the weight of the silica gel.
Claim 10
Dependent Claim
38 words
In the chromatographic resolution of a racemic mixture into its optical antipodes by contacting a solution of the mixture with an adsorbent, the improvement which comprises employing as the adsorbent a silica gel-immobilized (co)polymer according to claim 3.
Claim 11
Dependent Claim
15 words
The process according to claim 1, wherein the racemate being chromatographically resolved is a dihydropyridine.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1993-06-25 | 1993-12-25 | 1994-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-25 | 1997-12-25 | 1998-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-25 | 2001-12-25 | 2002-06-26 | $7700.00 | Window Closed / Lapsed |