Recyclable metathesis catalysts

Abstract

Highly active, recoverable and recyclable transition metal-based metathesis catalysts and their organometallic complexes including dendrimeric complexes are disclosed, including a Ru complex bearing a 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene and styrenyl ether ligand. The heterocyclic ligand significantly enhances the catalytic activity, and the styrenyl ether allows for the easy recovery of the Ru complex. Derivatized catalysts capable of being immobilized on substrate surfaces are also disclosed. The present catalysts can be used to catalyze ring-closing metathesis (RCM), ring-opening (ROM) and cross metatheses (CM) reactions, and promote the efficient formation of various trisubstituted olefins at ambient temperature in high yield.

1 . A transition metal catalyst comprising:
 a substrate having at least one functional group;   a transition metal having at least one substituent that reacts with at least one functional group on the substrate to chemically bond the transition metal to the substrate, the transition metal selected from the group consisting of ruthenium, osmium and tungsten.   
     
     
         2 . The transition metal catalyst of  claim 1  wherein the substituent is selected from the group consisting of alkyl halosilanes, akenyl halosilanes, alkoxy halosilanes, aryloxy halosilanes, aryl halosilanes, alkyl halides, cycloalkyl halides, alkenyl halides, cycloalkenyl halides, aromatic and heteroaromatic halides, acid chlorides, anhydrides, succimidyl esters, epoxides, thiols, acrylate, methacrylate, acrylamide, methacrylamide, benzophenone, and derivatives thereof. 
     
     
         3 . The transition metal catalyst of  claim 1  wherein the substituent is alkylldimethylsilylcholride. 
     
     
         4 . The transition metal catalyst of  claim 1  wherein the substrate is a porous or a non-porous solid phase. 
     
     
         5 . The transition metal catalyst of  claim 1  wherein the substrate is selected from the group consisting of glasses, metals, non-metals, ceramics, rubbers and polymeric materials. 
     
     
         6 . The transition metal catalyst of  claim 1  wherein the substrate is part of a containing vessel. 
     
     
         7 . A composition comprising a transition metal catalyst having the following structure: 
       
         
           
           
               
               
           
         
       
       wherein A is a polyvalent atom selected from the group consisting of carbon, nitrogen, silicon and phosphorous; 
       wherein R 5 , R 6 , R 7  and R 8  each comprises the following structure: 
       
         
           
           
               
               
           
         
         wherein: 
         M comprises a transition metal; 
         X comprises oxygen, sulfur, nitrogen or phosphorus; 
         R comprises an alkyl, alkenyl, alkynyl, aryl, alkoxy, alkenyloxy, alkynyloxy, aryloxy, alkoxy carbonyl, alkylamino, alkylthio, alkylsulfonyl, or alkylsulfinyl; each optionally substituted with an alkyl, halogen, aryl or heteroaryl moiety; 
         R 1  and R 2  each comprises, or together comprise, an electron withdrawing group; and 
         Z comprises an electron-donating heterocyclic carbene ligand or a phosphine group. 
       
     
     
         8 . The composition of  claim 7  wherein A is silicon. 
     
     
         9 . The composition of  claim 7  wherein M is a transition metal selected from the group consisting of ruthenium, osmium and tungsten. 
     
     
         10 . The composition of  claim 7  wherein M is ruthenium. 
     
     
         11 . The composition of  claim 7  wherein X is oxygen. 
     
     
         12 . The composition of  claim 7  wherein R is a lower alkyl group. 
     
     
         13 . The composition of  claim 7  wherein R is isopropyl. 
     
     
         14 . The composition of  claim 7  wherein each of R 1  and R 2  is a halogen. 
     
     
         15 . The composition of  claim 7  wherein each of R 1  and R 2  is chlorine. 
     
     
         16 . The composition of  claim 7  wherein Z comprises a phosphine moiety having the formula P(Cy) 3 . 
     
     
         17 . The composition of  claim 7  wherein Z comprises an aromatic ring structure having the following structure: 
       
         
           
           
               
               
           
         
       
       wherein R 3  and R 4  each comprises an aromatic ring moiety. 
     
     
         18 . A method of immobilizing a transition metal catalyst comprising:
 reacting the transition metal catalyst with a chemical coupling agent to form an adduct with the transition metal catalyst; and   contacting the adduct with a substrate to chemically bond the adduct with the substrate through covalent chemical bonding, ionic bonding, non-ionic interaction, or combinations thereof.   
     
     
         19 . The method of  claim 18  further comprising reacting the transition metal catalyst with a chemical coupling agent that is chemically bonded to the substrate. 
     
     
         20 . The method of  claim 18  wherein the chemical coupling agent comprises at least one compound selected from the group consisting of alkyl halosilanes, akenyl halosilanes, alkoxy halosilanes, aryloxy halosilanes and aryl halosilanes, alkyl and cycloalkyl halides, alkenyl and cycloalkenyl halides, aromatic and heteroaromatic halides, acid chlorides, anhydrides, succimidyl esters, epoxides and thiols. 
     
     
         21 . The method of  claim 18  wherein the chemical coupling agent is allylchlorodimethylsilane. 
     
     
         22 . The method of  claim 18  wherein the substrate is selected from the group consisting of glasses, metals, non-metals, ceramics, rubbers and polymeric materials. 
     
     
         23 . The method of  claim 18  wherein the substrate is a porous or non-porous material. 
     
     
         24 . The method of  claim 18  wherein the substrate is a porous sol-gel.