Iron complexes and methods for polymerization

Abstract

Provided are methods of preparing polymers, such as polyisoprene, polybutadiene, polypiperylene, polycyclohexadiene, poly-β-farnesene, or poly-β-myrcene, using iron complexes. Also provided are novel iron complexes, pre-catalysts, intermediates, and ligands useful in the inventive polymerization system.

1 - 48 . (canceled) 
     
     
         49 . An iron complex comprising a ligand of Formula (BI-a): 
       
         
           
           
               
               
           
         
       
       wherein:
 m is 0 or 1, provided that when m is 0, X is selected from N—R 4 ; and when m is 1, X is selected from N or C—R 4 ; 
 each instance of R 1 , R 2 , R 3 , R 4 , and R 5  is independently selected from the group consisting of hydrogen, halogen, —CN, —NO 2 , —N 3 , —SO 2 H, —SO 3 H, —OH, —SH, —NH 2 , substituted hydroxyl, substituted thiol, monosubstituted amino, disubstituted amino, trisubstituted amino, sulfonyl, sulfinyl, carbonyl, silyl, phosphino, boronyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; or R 1  and R 2 , or R 2  and R 3 , or R 2  and R 4 , or R 3  and R 4 , are optionally joined to form a ring selected from the group consisting of optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl ring; and 
 R 7 , R 8 , and R 9  are each independently optionally substituted alkyl. 
 
     
     
         50 . The iron complex of  claim 49 , wherein the ligand is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         51 . A method of preparing a polymer, the method comprising polymerizing one or more alkenes in the presence of an iron complex, wherein the iron complex comprises a ligand of the Formula (BI-a): 
       
         
           
           
               
               
           
         
       
       wherein:
 m is 0 or 1, provided that when m is 0, X is selected from N—R 4 ; and when m is 1, X is selected from N or C—R 4 ; 
 each instance of R 1 , R 2 , R 3 , R 4 , and R 5  is independently selected from the group consisting of hydrogen, halogen, —CN, —NO 2 , —N 3 , —SO 2 H, —SO 3 H, —OH, —SH, —NH 2 , substituted hydroxyl, substituted thiol, monosubstituted amino, disubstituted amino, trisubstituted amino, sulfonyl, sulfinyl, carbonyl, silyl, phosphino, boronyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; or R 1  and R 2 , or R 2  and R 3 , or R 2  and R 4 , or R 3  and R 4 , are optionally joined to form a ring selected from the group consisting of optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl ring; 
 R 7  and R 8  are each independently optionally substituted alkyl; 
 R 9  is hydrogen or optionally substituted alkyl; 
 and the one or more alkenes are independently an optionally substituted 1,3-diene of formula (i): 
 
       
         
           
           
               
               
           
         
       
       wherein:
 each instance of R a , R b , R c , R d , R e , and R f  is independently selected from the group consisting of hydrogen, silyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; 
 or R a  and R f  are joined to form an optionally substituted heterocyclyl or optionally substituted carbocyclyl ring. 
 
     
     
         52 . The method of  claim 51 , wherein the one or more alkenes is a compound of formula: 
       
         
           
           
               
               
           
         
       
       and the polymer is polyisoprene. 
     
     
         53 . The method of  claim 52 , wherein the polyisoprene is at least 50% 1,4-polyisoprene. 
     
     
         54 . The method of  claim 53 , wherein the polyisoprene is between about 50% to about 100% 1,4-cis-polyisoprene. 
     
     
         55 . The method of  claim 53 , wherein the polyisoprene is between about 50% to about 100% 1,4-trans-polyisoprene. 
     
     
         56 . The method of  claim 52 , wherein the polyisoprene comprises 1,4-cis-polyisoprene and 1,4-trans-polyisoprene in a ratio of between about 95:5 to about 100:0 1,4-cis-polyisoprene to 1,4-trans-polyisoprene. 
     
     
         57 . The method according to  claim 52 , wherein the polyisoprene comprises 1,4-trans-polyisoprene and 1,4-cis-polyisoprene in a ratio of between about 95:5 to about 100:0 1,4-trans-polyisoprene to 1,4-cis-polyisoprene. 
     
     
         58 . The method of  claim 52 , wherein the polyisoprene is less than 30% 3,4-polyisoprene. 
     
     
         59 . The method of  claim 52 , wherein the polyisoprene is less than 5% 1,2-polyisoprene. 
     
     
         60 . The method of  claim 51 , wherein each instance of R 7 , R 8 , and R 9  is optionally substituted alkyl. 
     
     
         61 . The method of  claim 51 , wherein each instance of R 7  and R 8  is —CH 3 . 
     
     
         62 . The method of  claim 51 , wherein R 9  is —CH 2 C(CH 3 ) 3 , —CH 2 C(CH 2 CH 3 ) 3 , —C(CH 3 ) 3 , —CH(CH 3 ) 2 , —CH 2 CH(CH 3 ) 2 , —CH 2 CH 2 CH 3 , —CH 2 CH 3 , —CH 3 , —CF 3 , —CH 2 Si(CH 3 ) 3 , —CH 2 Ph wherein Ph is phenyl, or —CH 2 CH═CH 2 . 
     
     
         63 . The method of  claim 51 , wherein the ligand is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         64 . A method of preparing a polymer, the method comprising polymerizing one or more alkenes in the presence of an iron complex, wherein the iron complex comprises a ligand of the Formula (EI-d10): 
       
         
           
           
               
               
           
         
       
       wherein:
 each instance of R 15  and R 19  is independently optionally substituted aryl or optionally substituted heteroaryl; 
 R 17  is hydrogen, halogen, —NO 2 , substituted amino, optionally substituted aryl, or optionally substituted heteroaryl; 
 each instance of R 1 , R 2 , R 3 , R 4 , and R 5  is independently selected from the group consisting of hydrogen, halogen, —CN, —NO 2 , —N 3 , —SO 2 H, —SO 3 H, —OH, —SH, —NH 2 , substituted hydroxyl, substituted thiol, monosubstituted amino, disubstituted amino, trisubstituted amino, sulfonyl, sulfinyl, carbonyl, silyl, phosphino, boronyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; or R 1  and R 2 , or R 2  and R 3 , or R 2  and R 4 , or R 3  and R 4 , or R 4  and R 5 , are optionally joined to form a ring selected from an optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl ring; 
 and the one or more alkenes are independently an optionally substituted 1,3-diene of formula (i): 
 
       
         
           
           
               
               
           
         
       
       wherein:
 each instance of R a , R b , R c , R d , R e , and R f  is independently selected from the group consisting of hydrogen, silyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; 
 or R a  and R f  are joined to form an optionally substituted heterocyclyl or optionally substituted carbocyclyl ring. 
 
     
     
         65 . The method of  claim 64 , wherein the ligand is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         66 . A method of preparing a polymer, the method comprising polymerizing one or more alkenes in the presence of an iron complex, wherein the iron complex comprises a ligand of the Formula (EI-d8): 
       
         
           
           
               
               
           
         
       
       wherein:
 R 15  is optionally substituted aryl or optionally substituted heteroaryl; 
 R 17  is hydrogen, halogen, —NO 2 , substituted amino, optionally substituted aryl, or optionally substituted heteroaryl; 
 each instance of R 1 , R 2 , R 3 , R 4 , and R 5  is independently selected from the group consisting of hydrogen, halogen, —CN, —NO 2 , —N 3 , —SO 2 H, —SO 3 H, —OH, —SH, —NH 2 , substituted hydroxyl, substituted thiol, monosubstituted amino, disubstituted amino, trisubstituted amino, sulfonyl, sulfinyl, carbonyl, silyl, phosphino, boronyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; or R 1  and R 2 , or R 2  and R 3 , or R 2  and R 4 , or R 3  and R 4 , or R 4  and R 5 , are optionally joined to form a ring selected from an optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl ring; 
 and the one or more alkenes are independently an optionally substituted 1,3-diene of formula (i): 
 
       
         
           
           
               
               
           
         
       
       wherein:
 each instance of R a , R b , R c , R d , R e , and R f  is independently selected from the group consisting of hydrogen, silyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; 
 or R a  and R f  are joined to form an optionally substituted heterocyclyl or optionally substituted carbocyclyl ring. 
 
     
     
         67 . The method of  claim 66 , wherein the ligand is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         68 . A method of preparing a polymer, the method comprising polymerizing one or more alkenes in the presence of an iron complex, wherein the iron complex comprises a ligand of the Formula: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         and the one or more alkenes are independently an optionally substituted 1,3-diene of formula (i): 
       
       
         
           
           
               
               
           
         
       
       wherein:
 each instance of R a , R b , R c , R d , R e , and R f  is independently selected from the group consisting of hydrogen, silyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl; 
 or R a  and R f  are joined to form an optionally substituted heterocyclyl or optionally substituted carbocyclyl ring.