Ruthenium polymerisation catalysts

Abstract

Cis and trans ruthenium complexes that can be used as catalysts for ring opening metathesis polymerisation (ROMP) are described. The complexes are generally square pyramidal in nature, having two anionic ligands X. Corresponding cationic complexes where one or both of the anionic ligands X are replaced by a non-co-ordinating anionic ligand are also described. Polymers such as polydicyclopentadiene (PDCPD) can be prepared using the catalysts.

1 . A method of catalyzing a metathesis reaction comprising:
 contacting a monomer comprising at least one olefin and/or alkyne functional group with a trans ruthenium complex according to formula II:   
       
         
           
           
               
               
           
         
         wherein for each occurrence the groups X are the same or different and are anionic ligands or are fused to form a bidentate ligand; 
         the groups R 1  and R 2  are the same or different and are selected from the group consisting of hydrogen, C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C2-C20 alkoxycarbonyl, aryl, C1-C20 carboxylate, C1-C20 alkoxy, C2-C20 alkenyloxy, C2-C20 alkynyloxy, aryloxy, C1-C20 alkylthio, C1-C20 alkylsulfonyl, and C1-C20 alkylsulfinyl; and when not hydrogen are optionally substituted; or 
         the groups R 1  and R 2  are fused together to form a ring that may be substituted or unsubstituted, saturated or unsaturated and may be fused to a further ring; and 
       
       the group Z is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         wherein the groups R 3 , R 4  and R 5  are each independently for each occurrence selected from the group consisting of substituted or unsubstituted primary, secondary or tertiary alkyl, that may be cyclic and may be unsaturated; substituted or unsubstituted aryl or heteroaryl; and optionally two or more of the groups R 3 , R 4  and R 5  are fused to form a ring; 
         the group A is selected from the group consisting of a nucleophilic carbene, and a phosphorus ligand independently selected from the list of groups as defined for group Z, with the provisos that; 
         both groups Z and A are not phosphine and where A is a nucleophilic carbene, Z is not phosphine; and when A is a nucleophilic carbene, Z is not phosphine; and 
         causing metathesis polymerisation of the monomer, for a time and at a temperature capable of causing metathesis polymerisation. 
       
     
     
         2 . The method according to  claim 1  wherein the group Z is selected from the group consisting of 
       
         
           
           
               
               
           
         
       
     
     
         3 . The method according to  claim 1  wherein the group A is an N-heterocyclic carbene. 
     
     
         4 . The method according to  claim 1  wherein the anionic ligands X are independently selected from the group consisting of halogen, benzoate, C 1 -C 5  carboxylates. 
     
     
         5 . The method according to  claim 1  wherein the groups R 1  and R 2  are H and aryl. 
     
     
         6 . The method according to  claim 1  wherein the groups R 1  and R 2  are fused to form a substituted or unsubstituted indenylidene moiety. 
     
     
         7 . The method according to  claim 1  wherein the group A is an N-heterocyclic carbene selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
     
     
         8 . The method according to  claim 1  wherein the anionic ligands X are independently selected from the group consisting pivalate, trifluoroacetate, C 1 -C 5  alkoxy, phenoxy, C 1 -C 5  alkyl thio, tosylate, mesylate, brosylate, trifluoromethane sulfonate, phenylacetate, and pseudo-halogen. 
     
     
         9 . The method according to  claim 1  wherein the group Z is: 
       
         
           
           
               
               
           
         
       
     
     
         10 . The method according to  claim 9  wherein the groups R 1  and R 2  are fused together to form a ring that may be substituted or unsubstituted, saturated or unsaturated and may be fused to a further ring. 
     
     
         11 . The method according to  claim 9  wherein the groups R 1  and R 2  are fused to form a substituted or unsubstituted indenylidene moiety. 
     
     
         12 . The method according to  claim 9  wherein the group A is an N-heterocyclic carbene. 
     
     
         13 . The method according to  claim 9  wherein the group A is: 
       
         
           
           
               
               
           
         
       
     
     
         14 . The method according to  claim 9  wherein R 4  and R 5  are aryl. 
     
     
         15 . The method according to  claim 9  wherein R 4  and R 5  are phenyl. 
     
     
         16 . The method according to  claim 9  wherein R 3  is selected from the group consisting of substituted or unsubstituted primary alkyl and substituted or unsubstituted aryl. 
     
     
         16 . The method according to  claim 9  wherein R 3  is methyl, ethyl or phenyl. 
     
     
         17 . The method of  claim 1 , further comprising the steps of:
 before the metathesis step, forming a mixture of the monomer and the ruthenium polymerisation catalyst of formula II at a temperature wherein the step of metathesis polymerisation of the monomer is latent; and   subsequently heating the mixture such that the monomer is polymerized.   
     
     
         18 . The method of  claim 17 , wherein the mixture is introduced into a mold prior to the subsequent heating step such that the mixture conforms to the mold. 
     
     
         19 . A ruthenium complex of the formula: 
       
         
           
           
               
               
           
         
       
       wherein for each occurrence the groups X are the same or different and are anionic ligands or are fused to form a bidentate ligand;
 the groups R 1  and R 2  are fused together to form a ring that may be substituted or unsubstituted, saturated or unsaturated and may be fused to a further ring; 
 
       the group Z is 
       
         
           
           
               
               
           
         
         wherein the groups R 3 , R 4  and R 5  are each independently for each occurrence selected from the group consisting of substituted or unsubstituted primary, secondary or tertiary alkyl, that may be cyclic and may be unsaturated; substituted or unsubstituted aryl or heteroaryl; and optionally two or more of the groups R 3 , R 4  and R 5  are fused to form a ring; and 
         the group A is a nucleophilic carbene. 
       
     
     
         20 . The complex according to  claim 19  wherein the groups R 1  and R 2  are fused to form a substituted or unsubstituted indenylidene moiety. 
     
     
         21 . The complex according to  claim 19  wherein group A is an N-heterocyclic carbene. 
     
     
         22 . The complex according to  claim 19  wherein group A is: 
       
         
           
           
               
               
           
         
       
     
     
         23 . The complex according to  claim 19  wherein the group A is: 
       
         
           
           
               
               
           
         
       
     
     
         24 . A latent ROMP catalyst composition comprising:
 a ruthenium complex of the formula:   
       
         
           
           
               
               
           
         
         wherein for each occurrence the groups X are the same or different and are anionic ligands or are fused to form a bidentate ligand; 
         the groups R 1  and R 2  are fused together to form a ring that may be substituted or unsubstituted, saturated or unsaturated and may be fused to a further ring; 
       
       the group Z is 
       
         
           
           
               
               
           
         
         wherein the groups R 3 , R 4  and R 5  are each independently for each occurrence selected from the group consisting of substituted or unsubstituted primary, secondary or tertiary alkyl, that may be cyclic and may be unsaturated; substituted or unsubstituted aryl or heteroaryl; and optionally two or more of the groups R 3 , R 4  and R 5  are fused to form a ring; and 
         the group A is a nucleophilic carbene; and 
         one or more of: a solvent; or a monomer comprising at least one olefin and/or alkyne functional group.