Nonpolar phase-soluble methathesis catalysts

Abstract

One embodiment of the invention provides polyisobutylene (PIB) oligomers that are end-functionalized with ruthenium (Ru) catalysts. Such nonpolar catalysts can be dissolved in nonpolar solvents such as heptane, or any other nonpolar solvent that is otherwise not latently biphasic (i.e., if two or more solvent components are present, they remain miscible with each other throughout the entire reaction process, from the addition of substrate through to the removal of product). Substrate that is dissolved in the nonpolar solvent with the catalyst is converted into product. The lower solubility of the product in the nonpolar solvent renders it easily removable, either by extraction with a more polar solvent or by applying physical means in cases where the product precipitates from the nonpolar solvent. In this manner the catalysts are recycled; since the catalysts remain in the nonpolar solvent, a new reaction can be initiated simply by dissolving fresh substrate into the nonpolar solvent.

1 . A reaction composition comprising:
 a) a nonpolar solvent, wherein the solvent is not latently biphasic;   b) a catalyst that is complexed to a nonpolar support, wherein the catalyst-support complex is dissolved in the solvent; and   c) a substrate molecule dissolved in the solvent, wherein the molecule is a substrate for the catalyst, and wherein the product of a reaction of the molecule with the catalyst is less soluble in the solvent compared to the molecule.   
   
   
       2 . The composition of  claim 1 , wherein the product is completely insoluble in the solvent. 
   
   
       3 . The composition of  claim 1 , wherein the catalyst is a nucleophilic organic group. 
   
   
       4 . The composition of  claim 1 , wherein the catalyst is a triorganophosphine. 
   
   
       5 . The composition of  claim 1 , wherein the catalyst comprises an imidazole group, a thiazole group, or a pyridine group. 
   
   
       6 . The composition of  claim 1 , wherein the catalyst comprises a functional group selected from the group consisting of hydrocarbons, hydrocarbons containing one or more ester groups, hydrocarbons containing one or more ether groups, and hydrocarbons containing one or more amine groups. 
   
   
       7 . The composition of  claim 1 , wherein the catalyst comprises a metal atom. 
   
   
       8 . The composition of  claim 1 , wherein the catalyst comprises ruthenium. 
   
   
       9 . The composition of  claim 1 , wherein the catalyst comprises silver. 
   
   
       10 . The composition of  claim 1 , wherein the nonpolar support comprises polyisobutylene, polyethylene, poly(N-octadecylacrylamide), polysiloxane, polyamidoamine, poly(1-alkene), or polypropylene. 
   
   
       11 . The composition of  claim 1 , wherein the nonpolar support comprises polyisobutylene. 
   
   
       12 . The composition of  claim 1 , wherein the catalyst-support complex comprises an N-heterocyclic carbene moiety. 
   
   
       13 . The composition of  claim 1 , wherein the solvent comprises toluene, dichloromethane, dibutyl ether, or an alkane. 
   
   
       14 . The composition of  claim 1 , wherein the solvent consists of one component. 
   
   
       15 . The composition of  claim 14 , wherein the solvent is heptane. 
   
   
       16 . The composition of  claim 1 , wherein the substrate molecule is a substrate for a ring-closing, ring-opening or cross metathesis polymerization reaction. 
   
   
       17 . A reaction composition comprising:
 a) a solvent consisting of heptane;   b) a catalyst comprising ruthenium, wherein the catalyst is complexed to a support comprising polyisobutylene, and wherein the catalyst-support complex is dissolved in the solvent; and   c) a heptane-soluble substrate molecule, wherein the molecule is a substrate for the catalyst, and wherein the product of a reaction of the molecule with the catalyst is less soluble in heptane compared to the molecule.   
   
   
       18 . The composition of  claim 17 , wherein the product is completely insoluble in heptane. 
   
   
       19 . A method of catalyzing a chemical reaction, the method comprising:
 a) providing a reaction composition according to  claim 1 ;   b) allowing the substrate molecule to be catalyzed into product; and   c) separating the product from the reaction composition by
 i) removing the product by physical means, wherein the product is insoluble in the nonpolar solvent; or 
 ii) extracting the product by adding and removing a second solvent to the reaction composition, wherein the product is preferably soluble in the second solvent compared to the nonpolar solvent; 
   wherein the catalyst-support complex remains dissolved in the nonpolar solvent throughout the entire process.   
   
   
       20 . The method of  claim 19 , wherein the physical means comprise siphoning, filtering, or decanting. 
   
   
       21 . The method of  claim 19 , wherein the second solvent is a polar organic solvent. 
   
   
       22 . The method of  claim 19 , wherein the second solvent comprises acetonitrile. 
   
   
       23 . The method of  claim 19 , further comprising step d: reusing the catalyst-support complex by dissolving fresh substrate into the nonpolar solvent. 
   
   
       24 . The method of  claim 19 , wherein the catalyst-support complex comprises an N-heterocyclic carbene moiety.