EP0386926A2
Expired / Lapsed
EP
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Silica gel supports suitable for chromatographic separations
Assignee: Supelco Inc
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Filing: 1990-02-27
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Granted: —
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Expires: 2010-02-27
Abstract
Abstract Silica gel chromatographic supports surface-modified by reaction with (R¹O) 3-m Si R² m (CH₂)₃NH(CH₂CH₂NH) n H, in which R¹ is a C₁-C₅ alkyl, R² is methyl or ethyl, and m and n are independently selected from the integers 0, 1 or 2, and further modified chemically to produce reverse-phase character, markedly reduce the interaction between silanophilic analytes and the silanol groups present on the surface of the silica gel through the presence of polar groups, which include the residual unmodified amino and modified amino groups, and which are densely packed near the silica surface. This results in chromatographic elution of basic, silanophilic analytes in efficient, narrow bands similar to those of the less-polar analytes.
Inventors
- 👤 Binyamin Feibush
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 19:31
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/286; B01J20/02; B01J20/10; B01J20/103; B01J20/28; B01J20/28002; B01J20/28004; B01J20/28014; B01J20/28047; B01J20/28054; B01J20/28057; B01J20/287; B01J20/291; B01J20/30; B01J20/3092; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3231; B01J20/3242; B01J20/3244; B01J20/3246; B01J20/3257; B01J20/3259; B01J20/3261; B01J2220/00; B01J2220/50; B01J2220/54; B01J2220/58
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
78 words
A silica gel support suitable for use in chromatographic separations which comprises silica gel, to the surface of which is bonded from about 2 µmole/m² to about 10 µmole/m² of a modified aminosilyl group having the formula -Si R¹ m (CH₂)₃NH(CH₂CH₂NH) n -R², in which R¹ is methyl or ethyl, m and n are independently selected from the integers 0, 1 or 2, and R² is a group which produces a reverse-phase character in the modified aminosilyl group.
Claim 2
Dependent Claim
78 words
A silica gel support suitable for use in chromatographic separations which comprises silica gel, to the surface of which is bonded from about 2 µmole/m² to about 10 µmole/m² of a modified aminosilyl group having the formula -Si R¹ m (CH₂)₃NH(CH₂CH₂NH) n -R², in which R¹ is methyl or ethyl, m and n are independently selected from the integers 0, 1 or 2, and R² is a group which produces a reverse-phase character in the modified aminosilyl group.
Claim 3
Dependent Claim
19 words
A silica gel support as claimed in Claim 1, wherein m is 0 and n is 0 or 1.
Claim 4
Dependent Claim
15 words
A silica gel support as claimed in claim 2, wherein R¹ is methyl or ethyl.
Claim 5
Dependent Claim
19 words
A silica gel support as claimed in Claim 1, wherein m is 0 or 1 and n is 1.
Claim 6
Dependent Claim
92 words
A silica gel support as claimed in any preceding Claim, wherein R² is C₄ to C₂₂ alkyl, an alkyl carbamate group having from 4 to 22 carbon atoms in the alkyl portion of the group, a carboxyalkyl group containing from 4 to 22 carbon atoms in the alkyl portion of the group, a sulfoxyalkyl group containing from 3 to 19 carbon atoms in the alkyl portion of the group, or a sulfoxyaryl group in which the aryl group is optionally substituted with an alkyl group containing from 1 to 16 carbon atoms.
Claim 7
Dependent Claim
45 words
A silica gel support as claimed in Claim 1, wherein R² is an alkyl carbamate group containing 19 carbon atoms, a carboxyalkyl group containing 16 carbon atoms, or a sulfoxyaryl group in which the aryl group is -⌀-CH₃, the symbol ⌀ representing a phenyl group.
Claim 8
Dependent Claim
110 words
A process for the preparation of silica gel support as claimed in any of Claims 1 to 6, which comprises the steps, carried out in order, of a. reacting a silica gel with an aminosilylating reagent having the formula (R³0) 3-m SiR¹ m (CH₂)₃NH(CH₂CH₂NH) n H, in which R¹ is methyl or ethyl, R³ is a C₁ to C₅ alkyl, and m and n are independently selected from the integers 0, 1 or 2, b. reacting the resulting aminosilylated surface with a second reagent which introduces, into the aminosilyl group, a group which produces a reverse phase character therein, and c. isolating the surface-modified silica gel from the reaction mixture.
Claim 9
Dependent Claim
23 words
A process as claimed in Claim 7, wherein the second reagent is selected from acylating reagents, sulfonating reagents, carbamylating reagents and alkylating reagents.
Claim 10
Dependent Claim
30 words
A process as claimed in Claim 7 or Claim 8, wherein the second reagent is reacted with the aminosilylated surface in an aprotic, polar suspending solvent, for example, methylene chloride.
Claim 11
Dependent Claim
40 words
A process as claimed in any of Claims 7 to 9, wherein the second reagent is reacted with the aminosilylated surface in the presence of a scavenger for acid produced in the reaction, for example, in the presence of 4-dimethylaminopyridine.
Claim 12
Dependent Claim
46 words
A process as claimed in any of Claims 7 to 10, wherein the silica gel is reacted with the aminosilylating reagent in the presence of a non-reactive solvent at elevated temperature, for example, in the presence of toluene and at the reflux temperature of the toluene.
References Cited (Backward Citations)
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