Method of chelating anions from a liquid using a composition comprising at least one macrocyclic hosting moiety
A method of sequestering anions from a liquid including the anions includes contacting a composition comprising at least one macrocyclic moiety with the liquid. The macrocyclic moiety includes groups including an electropositive E-H bond donor extending into a cavity of the macrocyclic moiety wherein E is selected from the group consisting of C, N, and O, wherein two or more groups including an electropositive E-H donor interact with an anion to form a chelate with the anion.
1 . A method of chelating anions from a liquid including the anions, comprising:
contacting a composition comprising at least one macrocyclic moiety with the liquid, the at least one macrocyclic moiety being formed by providing an end group including a macrocyclic compound selected from the group consisting of
a resorcin[n]arene wherein n is an integer between 4 and 8,
a bridged resorcin[n′]arene wherein n′ is an integer between 4 and 8,
a calix[n″]pyrrole-resorcin[n]arene wherein n″ is 4, and
a calix[n′″]arene wherein n′″ is an integer between 4 and 6,
wherein the macrocyclic compound is sufficiently rigid that it presents a plurality of functional groups extending from a first axial side of the macrocyclic compound, and
reacting a plurality of reactive compounds with the plurality of functional groups extending from the first axial side of the macrocyclic compound,
wherein each of the plurality of reactive compounds is a precursor for one of a plurality of groups conjugated to the macrocyclic compound to extend from the first axial side thereof,
each of the plurality of groups conjugated to the macrocyclic compound including one or more electropositive C—H bond donor groups, H atoms of the C—H bond donor groups extending into a cavity of the at least one macrocyclic moiety, and at least one electron withdrawing substituent,
wherein at least one of the one or more electropositive C—H bond donor groups of two or more of the plurality of groups interacts with one of the anions to form a chelate with the one of the anions.
2 . The method of claim 1 wherein each of the plurality of groups including the one or more electropositive C—H bond donor groups is selected from the group consisting of an aromatic group and a heterocyclic aromatic group.
3 . The method of claim 1 wherein each of the plurality of groups including the one or more electropositive C—H bond donor groups of the macrocyclic moiety are aromatic groups.
4 . The method of claim 1 wherein the macrocyclic moiety exhibits an affinity toward anions that are non-spherical anions.
5 . The method of claim 4 wherein the macrocyclic moiety exhibits an affinity for anions that are large anions.
6 . The method of claim 5 wherein the macrocyclic moiety has an affinity for at least one of sulfonates and carboxylates.
7 . The method claim 1 wherein a plurality of the macrocyclic moieties are immobilized upon a surface of a solid or covalently incorporated within a polymer.
8 . The method of claim 1 wherein the plurality of groups including the one or more electropositive C—H bond donor groups are conformationally constrained.
9 . The method of claim 1 wherein each of the plurality of groups including the one or more electropositive C—H bond donor groups has the formula:
wherein each of R 1 , R 2 , R 3 , R 4 , and R 5 is independently selected from the group consisting of H and an electron withdrawing group, and wherein at least one of R 1 , R 2 , R 3 , R 4 , and R 5 is H.
10 . The method of claim 9 wherein each of R 1 , R 2 , R 3 , R 4 , and R 5 is independently selected from the group consisting of H, F, CN, NO 2 , SO 2 CF 3 , NR 3 +, SO 3 H, SO 2 R, COR, CO 2 H, CO 2 R, CONH 2 , CONHR, and CONR 2 , wherein R is an alkyl group having one and up to 20 carbon atoms, or an aryl group with or without substituents, where substituents may include any one or combinations of the following groups F, CN, NO 2 , SO 2 CF 3 , and wherein at least one of R 1 , R 2 , R 3 , R 4 , and R 5 is H.
11 . The method of claim 9 wherein each of R 1 , R 2 , R 3 , R 4 , and R 5 is independently selected from the group consisting of H, F, CN, and NO 2 , and wherein at least one of R 1 , R 2 , R 3 , R 4 , and R 5 is H.
12 . The method of claim 1 wherein each of the plurality of groups including the electropositive C—H bond donor groups has the formula:
13 . The method of claim 12 wherein the macrocyclic moiety is a resorcin[n]arene wherein n is 4.
14 . The method of claim 1 wherein the macrocyclic compound is generally cylindrical or ellipsoidal.
15 . The method of claim 1 wherein the macrocyclic compound comprise arene groups.
16 . The method of claim 1 wherein the plurality of functional groups extending from the first axial side of the macrocyclic compound are selected from the group consisting of halide groups, boronate esters, and acetylenic groups.
17 . The method of claim 1 wherein the macrocyclic compound further comprises a plurality of functional groups on a second axial side of the macrocyclic compound.
18 . The method of claim 17 wherein the plurality of functional groups on the second axial side of the macrocyclic compound are selected from the group consisting of an alkyl group, an aryl group, an aldehyde group, an alkyl halide, an alcohol group, an ether group, an alkyl epoxide group, an olefinic group, an acetylenic group, carboxylic group, or a polymeric group.
19 . The method of claim 17 wherein at least a portion of the plurality of functional groups on the second axial side of the macrocyclic compound are selected to react in a polymerization reaction.
20 . The method of claim 1 wherein the macrocyclic compound is:
wherein R′ is a hydroxyl group or an alkoxy, R″ is a halide, a boronate ester group, an acetylenic group, an amine group, an amide group, a urea group, a thiourea group, an aldehyde group, or a carboxylic group, R′″ is a halide group, a hydroxyl group, an alkoxy group, an amine group, an aldehyde group, an imine group, or a carboxylic group, and R is an alkyl group, an aryl group, an aldehyde group, an alkyl halide, an alcohol group, an ether group, an alkyl epoxide group, an olefinic group, an acetylenic group, a carboxylic group, or a polymeric group.
21 . The method of claim 1 wherein the anions are perfluorinated compounds and polyfluorinated compounds.
22 . The method of claim 1 wherein the at least one macrocyclic moiety also interact with neutral compounds to sequester a neutral compound.
23 . The method of claim 1 wherein a plurality of the macrocyclic moieties of different ring size are immobilized upon a surface of a solid or covalently incorporated within a polymer to sequester anions of different size.