Latent, high-activity olefin metathesis catalysts containing an N-heterocyclic carbene ligand

Abstract

The invention provides novel organometallic complexes useful as olefin metathesis catalysts. The complexes have an N-heterocyclic carbene ligand and a chelating carbene ligand associated with a Group 8 transition metal center. The molecular structure of the complexes can be altered so as to provide a substantial latency period. The complexes are particularly useful in catalyzing ring closing metathesis of acyclic olefins and ring opening metathesis polymerization of cyclic olefins.

1 . An organometallic complex comprising a Group 8 transition metal having an N-heterocyclic carbene ligand and an alkylidene group contained within a cyclic structure, wherein the complex is capable of catalyzing an olefin metathesis reaction with a latency period of at least two minutes.  
   
   
       2 . The organometallic complex of  claim 1 , capable of catalyzing an olefin metathesis reaction with a latency period of at least five minutes.  
   
   
       3 . The organometallic complex of  claim 1 , wherein the olefin metathesis reaction is ring closing metathesis.  
   
   
       4 . The organometallic complex of  claim 1 , wherein the olefin metathesis reaction is ring opening metathesis polymerization.  
   
   
       5 . The organometallic complex of  claim 2 , wherein the olefin metathesis reaction is ring closing metathesis.  
   
   
       6 . The organometallic complex of  claim 2 , wherein the olefin metathesis reaction is ring opening metathesis polymerization.  
   
   
       7 . A complex having the structure of formula (I)  
     
       
         
         
             
             
         
       
       wherein:  
       α and β represent single bonds or unsaturated bonds, with the proviso that α and β cannot both be unsaturated bonds;  
       M is a Group 8 transition metal;  
       R 1  and R 2  are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;  
       Q is an organic diradical;  
       X 1  and X 2  are anionic ligands, and may be the same or different;  
       L 1  is a neutral electron donor ligand, and p is zero or 1;  
       when α is a single bond, L 2  is selected from NR 7 R 8 , PR 7 R 8 , N═CR 7 R 8 , and R 7 C═NR 8 , where R 7  and R 8  are independently selected from substituted and/or heteroatom-containing C 1 -C 20  alkyl, C 2 -C 20  alkenyl, C 2 -C 20  alkynyl, and C 5 -C 24  aryl, or R 7  and R 8  can be taken together to form a heterocyclic ring;  
       when α is an unsaturated bond, L 2  is selected from NR 7  and PR 7 , where R 7  is as defined previously, or L 2  and Z represent adjacent atoms in an aromatic ring;  
       Y and Z are linkages independently selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, —O—, —S—, —NR 9 —, and —PR 9 —, wherein R 9  is selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and further wherein Y and Z may represent adjacent atoms in an aromatic ring;  
       m is zero or 1; and  
       n is zero or 1,  
       as well as isomers thereof.  
     
   
   
       8 . A complex having the structure of formula (II)  
     
       
         
         
             
             
         
       
       wherein:  
       β represent a single bond or an unsaturated bond;  
       M is a Group 8 transition metal;  
       R 1  and R 2  are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;  
       Q is an organic diradical;  
       X 1  and X 2  are anionic ligands, and may be the same or different;  
       L 1  is a neutral electron donor ligand, and p is zero or 1;  
       R 7  and R 8  are independently selected from substituted and/or heteroatom-containing C 1 -C 20  alkyl, C 2 -C 20  alkenyl, C 2 -C 20  alkynyl, and C 5 -C 24  aryl, or R 7  and R 8  can be taken together to form a heterocyclic ring; and  
       Y and Z are linkages independently selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, —O—, —S—, —NR 9 —, and —PR 9 —, wherein R 9  is selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and further wherein Y and Z may represent adjacent atoms in an aromatic ring,  
       as well as isomers thereof.  
     
   
   
       9 . The complex of  claim 8 , wherein R 7  and R 8  are C 1 -C 12  alkyl or C 5 -C 12  aryl, and Y is a substituted or unsubstituted methylene or ethylene linkage.  
   
   
       10 . A complex having the structure of formula (III)  
     
       
         
         
             
             
         
       
       wherein:  
       β represent a single bond or an unsaturated bond;  
       M is a Group 8 transition metal;  
       R 1  and R 2  are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;  
       Q is an organic diradical;  
       X 1  and X 2  are anionic ligands, and may be the same or different;  
       L 1  is a neutral electron donor ligand, and p is zero or 1;  
       R 7  and R 8  are independently selected from substituted and/or heteroatom-containing C 1 -C 20  alkyl, C 2 -C 20  alkenyl, C 2 -C 20  alkynyl, and C 5 -C 24  aryl, or R 7  and R 8  can be taken together to form a heterocyclic ring; and  
       Y and Z are linkages independently selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, —O—, —S—, —NR 9 —, and —PR 9 —, wherein R 9  is selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and further wherein Y and Z may represent adjacent atoms in an aromatic ring,  
       as well as isomers thereof.  
     
   
   
       11 . The complex of  claim 10 , wherein R 7  and R 8  are C 1 -C 12  alkyl or C 5 -C 12  aryl, and Y is a substituted or unsubstituted methylene or ethylene linkage.  
   
   
       12 . The complex of  claim 11 , wherein R 7  and R 8  are phenyl and Y is ethylene.  
   
   
       13 . A complex having the structure of formula (IV)  
     
       
         
         
             
             
         
       
       wherein:  
       M is a Group 8 transition metal;  
       R 1  and R 2  are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;  
       Q is an organic diradical;  
       X 1  and X 2  are anionic ligands, and may be the same or different;  
       L 1  is a neutral electron donor ligand, and p is zero or 1; and  
       Y is a linkage selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, —O—, —S—, —NR 9 —, and —PR 9 —, wherein R 9  is selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl,  
       as well as isomers thereof.  
     
   
   
       14 . A complex having the structure of formula (V)  
     
       
         
         
             
             
         
       
       wherein:  
       M is a Group 8 transition metal;  
       R 1  and R 2  are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;  
       Q is an organic diradical;  
       X 1  and X 2  are anionic ligands, and may be the same or different;  
       L 1  is a neutral electron donor ligand, and p is zero or 1; and  
       R 7  is selected from substituted and/or heteroatom-containing C 1 -C 20  alkyl, C 2 -C 20  alkenyl, C 2 -C 20  alkynyl, and C 5 -C 24  aryl; and  
       Y and Z are linkages independently selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, —O—, —S—, —NR 9 —, and —PR 9 —, wherein R 9  is selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl,  
       as well as isomers thereof.  
     
   
   
       15 . A method for catalyzing an olefin metathesis reaction, comprising contacting an olefinic reactant with the catalytic complex of any one of claims  1 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 , or  14  under reaction conditions selected to enable olefin metathesis.